Volume 37, Issue 4 AIAA Houston Section www.aiaa-houston.org January / February 2012 First Confirmation: Planet Kepler-22b HubbleAn Revisited -Like Exoplanet on NASA’s in a Habitable 50th Anniversary Zone Wes Kelly, Triton Systems LLC

AIAA Houston Section Horizons January / February 2012 Page 1 January / February 2012

T A B L E O F C O N T E N T S

(Page numbers are linked on this page. To return here, click on tops of pages.) From the Chair 3

HOUSTON From the Editor 4

Horizons is a bimonthly publication of the Houston Section Cover Story: Kepler-22b, by Wes Kelly, Triton Systems LLC 5 of the American Institute of Aeronautics and Astronautics. A Peek at Cassini After Seven Years in , by Daniel R. Adamo 14 Douglas Yazell Sustainable Use of Space Through Orbital Debris Control, by N. L. Johnson 18 Editor Past Editors: Dr. Steven E. Everett 1940 Air Terminal Museum at Hobby Airport 19 Editing team: Don Kulba, Ellen Gillespie, Robert Bere- mand, Alan Simon, Dr. Steven Everett, Shen Ge Isle of Man - An Excellent Space for Space, by Shen Ge 20 Regular contributors: Dr. Steven Everett, Don Kulba, Philippe Mairet, Alan Simon, Scott Lowther From our French Sister Section 3AF MP, Biodiversity and 22 Contributors this issue: Dr. Albert A. Jackson IV, Daniel R. Adamo, Wes Kelly Warp Drives: A Curious History, by Dr. Albert A. Jackson IV 26

AIAA Houston Section Phobos-Grunt’s Inexorable Trans-Mars Injection Countdown Clock, Adamo 30 Executive Council Phoenix-E, by Scott Lowther, Aerospace Projects Review 40

Sean Carter EAA Chapter 12 (Houston), The Experimental Aircraft Association 43 Chair Councilors Current Events 44 Daniel Nobles Irene Chan Chair-Elect Secretary Staying Informed 46

Sarah Shull John Kostrzewski AIAA Calendar 50 Past Chair Treasurer Cranium Cruncher 51 Julie Read Dr. Satya Pilla Vice-Chair, Operations Vice-Chair, Technical Section News 52

Operations Technical List of AIAA Conference Papers by AIAA Houston Section Members 54 Dr. Gary Turner Dr. Albert A. Jackson IV Shen Ge Bebe Kelly-Serrato The Back Cover: ISS Expedition 31 56 Melissa Gordon Dr. Zafar Taqvi Lisa Voiles Bill Atwell Horizons and AIAA Houston Web Site Rafael Munoz Sheikh Ahsan AIAA National Communications Award Winner Svetlana Hanson William West Michael Frostad Paul Nielson Dr. Benjamin Longmier Dr. Steven E. Everett Matthew Easterly Gary Brown Douglas Yazell Dr. Kamlesh Lulla Gary Cowan Ludmila Dmitriev-Odier Joel Henry Alan Sisson

2005 2006 2007 Ellen Gillespie This newsletter is created by members of the Houston section. Opinions expressed herein other than Brian Banker by elected Houston section officers belong solely to the authors and do not necessarily represent the Matt Johnson position of AIAA or the Houston section. Unless explicitly stated, in no way are the comments of Clay Stangle individual contributors to Horizons to be construed as necessarily the opinion or position of AIAA, Melissa Kronenberger NASA, its contractors, or any other organization. All articles in Horizons, unless otherwise noted, Sarah Barr are the property of the individual contributors. Reproduction/republishing in any form except lim- Donald Barker ited excerpts with attribution to the source, will require the express approval of the individual au- Shirley Brandt thors. Please address all newsletter correspondence to editor-in-chief “at” aiaa-houston.org. Holly Feldman Gabe Garrett Cover: Planet Kepler 22-b. Image credits: NASA. Source: NASA press confer- www.aiaa-houston.org ence of December 5, 2011. Venus transit: Image credit and source: http:// blog.urbansedlar.com/wp-content/uploads/2012/02/800px- 20040608_Venus_Transit.jpg.

AIAA Houston Section Horizons January / February 2012 Page 2 Page 3

Events on the Horizon From the Chair SEAN CARTER, CHAIR

Both NASA and the Johnson detailed at: http:// Space Center in Florida. Its Space Center community find strategicplan.jsc..gov/. intention will be to success- themselves at a turning point fully dock the first 100% in our history. Last year As the AIAA Houston Sec- commercially designed and marked the retirement of the tion moves into this bold new built US to the much-heralded future together we are com- International Space Station Program and the abrupt can- mitted to meeting the exciting and, in that moment, usher in cellation of the Constellation new challenges and opportu- the dawn of a new era in com- program. These changes nities. mercializing low earth orbit. meant significant layoffs to our JSC community and many In March, we will be hearing more changes ahead. Many from the principal architect of were left confused and pessi- the JSC Strategic Plan, Dr. mistic about the future of hu- Douglas Terrier. Later in man space flight exploration. March, AIAA will host its Congressional Visits Day on Throughout the summer and Capitol Hill. In April we’ll fall of 2011 JSC Center Di- again host the AIAA Region rector, Mr. Michael Coats, IV Student Paper Competition and his staff were aggressive- aimed at inspiring human ly working to study this new exploration in space within environment and chart a new our Region IV universities. strategic course for JSC. Last Finally, in May, we are set to www.aiaa-houston.org month (January 2012), Mr. host the AIAA Annual Tech- Coats unveiled his new JSC nical Symposium. Strategic Implementation Plan that lays out the 4 JSC Strate- Lastly, likely before summer gic Goals and the success 2012, SpaceX plans to launch factors required to accomplish a historic mission where its those goals. Those goals can Dragon Rider will launch on be seen below and are further the Falcon 9 from Kennedy

AIAA Houston Section Horizons January / February 2012 Page 3 Page 4

From the Editor Climate Change, Confirmation Bias & Horizons DOUGLAS YAZELL, EDITOR

Climate change is addressed gist Jonathan Haidt from the Link to that video presenta- by presentations at national University of Virginia, author tion as seen on PBS: AIAA events. At our recent of the forthcoming book, The dinner meeting (our cover Righteous Mind. http://billmoyers.com/ story two issues ago), Con- segment/jonathan-haidt- gressman Olson stated that “Reasoning and Google can explains-our-contentious- NASA should be ordered to take you wherever you want culture/ stop climate monitoring be- to go.” is a quote from the cause, he said, that work is book. We all exhibit confir- NASA’s Kepler spacecraft redundant. mation bias. Once we make a continues to inspire with its claim, we stop seeking sup- exoplanet discoveries. Wes The NASA Alumni League port for it as soon as we find Kelly of Triton Systems LLC Chap- one nugget of evidence in our authors our cover story about ter (NAL-JSC) is tackling the favor. Reason is reliable only planet Kepler-22b. climate change controversy in diverse groups where our by fostering a local study reasoning can be challenged Thanks as always to our group, open to AIAA mem- by people we like and re- many contributors. I am late bers, that will focus on avail- spect. Only in those cases with my contributions this E-mail: able empirical data. Charts will truth emerge. In recent time as we work to meet our editor-in-chief [at] from recent presentations at years we rarely spend time in bimonthly schedule. With aiaa-houston.org their events are here: such groups. luck, I can do this for another year starting July 1, 2012. We Our web site www.aiaa- www.nal-jsc.org. One of Professor Haidt’s two always seek new members houston.org includes Horizons main messages in this inter- for our Horizons team, and back issues to 2005 or earlier. Months after the NAL-JSC view is, “Stop demonizing one day a new editor will be For earlier issues (an incom- events, I watched an episode the other side.” needed. plete archive being slowly of Moyers & Company on updated): https://info.aiaa.org/ Public Broadcasting System Moyers on Haidt: “His ideas Regions/SC/Houston/ (PBS) TV with Bill Moyers are controversial, but he Newsletters/Forms/ interviewing social psycholo- makes you think.” AllItems.aspx.

Above: Image Credit: NASA/NOAA/GSFC/ Above: Responding to public demand, NASA Suomi NPP/VIIRS/Norman Kuring. Image scientists created a companion image to the source: http://www.nasa.gov/multimedia/ wildly popular 'Blue Marble' released last imagegallery/image_feature_2159.html week (January 25, 2012). Credit: NASA/NOAA

AIAA Houston Section Horizons January / February 2012 Page 4 Page 5

Planet Kepler 22-b: An Historic Discovery Kepler-22b WES KELLY, TRITON SYSTEMS LLC

Finally, we’ve got one: an is to find what percentage of p. a8). Whether the Sun-like extra-solar planet (an ex- stars in our galaxy host Earth- stars are Main Sequence stars oplanet) in a habitable zone like planets in thermally hab- in general or perhaps more (the green zone in the cover itable zones. But the estimate narrowly defined as spectral illustration) near to Earth in needs to be drawn from sta- type “G”, the inference is that size. By the time this article is tistical study of planets of a there could be billions of published, we expect signifi- variety of sizes and distances such worlds in our galaxy. cant additions to the Kepler from their stars. The Kepler With the January 2012 Amer- Observatory planetary detec- team defined “super-” ican Astronomical Society tion list. But at this writing as extra-solar planets with conference in session in Aus- (January 2012), with some diameters up to twice Earth’s tin, presenters from the Space deserved fanfare, but not the diameter. Neptune has a di- Telescope Institute were esti- fanfare which centuries of ameter about four times that mating 100 billion planets in speculation and decades of of Earth’s and in the Solar the Milky Way Galaxy. work might have inspired, it System it is next after Earth was announced (05 December in ascending order of size The detection of extra-solar 2011) that a far-off planet among the planets. Neptune planets has progressed re- resembles Earth more than sets the diameter limit of the markably in the last two dec- any others found so far. Orbit- next category of planets in ades. Prior to 1995, attempts ing within its sun’s region of which Kepler-22b resides, to detect planets by position thermal habitability (see cover but this exoplanet lies closer (astrometric) measurements illustration), with a diameter to the super-Earth boundary of stars over years of obser- 2.4 times that of Earth’s, plan- than to Neptune, and well vation (e.g., the case of near- et Kepler-22b lies 620 light into the habitable zone. by Barnard’s star) were con- years or 190 parsecs away. Its founded by precision require- sun is a G5V star, slightly less As reported in December, ments and detected observa- luminous than our Sun in the more than 2,000 possible tional biases throwing meas- constellation of Cygnus the exoplanets have been detect- urements off. The 1990s Swan. We know this because ed, most as large as or larger breakthrough came with Dop- it transited in front of its pri- than Jupiter. Several dozen pler detection techniques in mary several times during received greater scrutiny, the visual bandwidth. Planets Kepler’s science observations, either because they resided in as large as Jupiter in tightly exhibiting an orbital period of the habitable temperature bound produced radial 290 days. Of planets so far zone of their parent stars, shifts in stellar velocities of detected beyond the solar they resembled the Earth in tens or even hundreds of me- system, this is the one where their dimensions or mass, or ters per second. Periodic ab- water’s presence has the best they exhibited other remarka- sorption line shifts to higher chance to mean precipitation, ble features. This last catego- and lower wavelengths in oceans and lakes. Or it could ry included densely populated stellar spectra could be de- be just another illustration of stellar systems and a planet in tected above all the other how much different a world orbit about a pair of stars (a turbulent behavior in the at- could be with larger girth, stellar binary). Based on the mospheres of distant suns. extra core or a different rain- statistical data derived from From this could be derived a down of volatile compounds the Kepler Observatory moni- projected radial velocity of an during formation. We have toring 150,000 stars since orbiting planet inversely pro- still much more to learn about 2009 for planetary transits, portional to the star and plan- the implications of “super- one study calculated that et mass ratio factored by the Earths” with diameters 1.25, “there ought to be about 23 cosine of inclination of the 2.0… or 2.4 times as wide as Earth-size planets for every orbit plane to the line of sight Earth’s diameter. 100 Sun-like stars” (Wall (LOS). In most cases the in- Street Journal - 21 Dec. 2011, clination was not known. The Kepler spacecraft mission (Continued on page 6)

AIAA Houston Section Horizons January / February 2012 Page 5 Page 6

Kepler-22b (Continued from page 5)

Transit detections were de- pendent on planets having no LOS . No matter to the observer that the transit was north-south or east -west, it was across the star’s observed surface even though from Earth it was little more than a point light source. If the planet was 1/10th the di- ameter of the star (as Jupiter is in proportion to the Sun), then it would block out 1/100th the light of a uniform- ly radiant disk; its angular rate Figure 3. Orbital Planes of Earth & Venus Inclined 3 degrees, of transit giving a clue to transit interval owing to time to repeated alignment at Figure 2. French philosopher, planar line of nodes. Image credit: Theresa Knott, public do- priest, astronomer, and mathe- when the transit would occur matician. First observer of a next. Were it a planet the size main. Image source: Wikipedia. planetary transit, of the Earth and the star as using the calculations of Johan- wide as the Sun, then the di- ameter and extinction ratios nes Kepler. Image credit: Pub- geometer’s perfect diameter once a planetary orbit can be would be 1/100th and drawing, but more likely detected at all by a space ob- lic domain. Image source: Wik- 1/10,000th respectively. some sort of chord. It is re- servatory. ipedia. markable that despite solar Whether small or large, we flares, sunspots and atmos- History would expect that not all pheric turbulence a stellar transits recorded would be a signal variation of 1/10,000th Solar planetary transits were first observed long before the space age – but very infre- quently. Since the Moon’s “transit” (eclipse) blots out the sun’s disk entirely due to the Moon’s proximity to the terrestrial observer, the first instinct of many (including me) would be to dismiss this method as a means of detect- ing objects in deep space – and yet it works. To validate the heliocentric system, trans- its of Venus and Mercury (Figure 1) were essential in determining the Earth’s dis- tance from the Sun. The or- bital plane of Venus is tilted 3 degrees from the plane of the ecliptic (Earth’s orbital plane), enough to make its solar transit a relatively rare event (Figure 2).

Figure 1a&b Planetary Transits of Venus and Mercury viewed from Earth. Figure 1a: Image cred- (Continued on page 7) it: see page 2. Figure 1b: Image credit: Mila Zinkova, public domain. Image source: Wikipedia.

AIAA Houston Section Horizons January / February 2012 Page 6 Page 7

(Continued from page 6) 2004, the last pair of transits great fear…”), since Galileo Transit predictions of Johan- was in December 1874 and had discovered satellites Kepler-22b nes Kepler’s orbital calcula- December 1882. The first of around a planet of our solar tions were confirmed by 17th the 21st century pair of Venus system rather than in orbit century observations in transits took place on 8 June about a star, not re- France, England and else- 2004; the next will be 6 June introducing issues related to where. The first recorded 2012. After 2012, plan for Bruno’s burning at the stake planetary solar transit was not December 2117 and Decem- in 1600 for heresy. Venus but Mercury by Jesuit ber 2125. priest and astronomer Pierre In a 1992 NASA Solar Sys- Gassendi in 1631 with Kep- Had anyone imagined that we tem Exploration Division ler’s data in hand (Figure 3). would someday watch for survey report titled “TOPS: He attempted to observe the transits of planets orbiting Toward Other Planetary Sys- transit of Venus in the same distant stars? Gassendi’s best tems” (a handy booklet I year, but in Paris it occurred known intellectual project picked up at the Lunar and at night. For centuries after attempted to reconcile Epicu- Planet Science Institute li- Gassendi’s missed opportuni- rean atomism with Christiani- brary one afternoon shortly ty, expeditions would subse- ty in the philosophical work after its publication), transit quently launch all over the Syntagma. As recently as was mentioned as a possible world to be in daylight for 2011 a best-seller titled means of “indirect planetary similar events: planetary “Swerve” by Yale Professor detection.” In turn it cited a transits, solar eclipses and Stephen Greenblatt re- 1984 paper in the planetary occultations of stars by a examines the influence of the science journal Icarus by co- planet or a moon. Epicurean writings of Lucreti- authors W. J. Borucki and A. us on the Renaissance. In J. Summers. This was men- Viewed from Earth, solar combination Democritus, tioned among the many ave- transits by the Moon, Venus Epicurus and the poet Lucreti- nues by which search for ex- and Mercury have different us provided arguments for a tra-solar planets might be geometries. Full solar eclipse multiplicity or worlds now pursued. by the Moon is a remarkable more than two millennia old. geometric fit even though the One would think that the con- In the 1980s William Borucki Moon is but 1,740 kilometers cept of planets around other working at NASA’s Ames in radius with the Sun at stars would result from a clear Research Center near 700,000 kilometers – 400 notion of stars being identi- Sunnyvale, CA had become times lunar radius. With Ve- fied as suns stemming from involved with extra-solar nus a third of the way to the pioneering work like Gali- planetary study groups, exam- Sun (orbital radius 0.67 AU), leo’s with telescopes, While ining the problem with astro- viewed from Earth, it is seen Epicurean doctrine allowed nomical photometry, an in- 3 times its size relative to the for other worlds with life, strumental approach of com- Sun in the photo. Mercury their connection to other suns puting a star’s overall lumi- (orbital radius 0.39 AU) is left to conjecture. In 1591, nosity. The TOPS report, be- shown only as a dot in the before Galileo (1564-1642) sides supplying planetary adjacent photo, is still exag- discovered Jupiter’s four larg- formation theory discussed in gerated by a factor of 1.64. est “Galilean” moons in 1610, the previous Horizons (pages These distortions disappear Giordano Bruno postulated, 18-21, www.aiaa-houston.org, for interstellar observation. “planets revolving around Nov. / Dec. 2011 issue), ex- other fixed stars, that is, amined numerous detection Transits of Venus are among suns.” This was a bow to Co- approaches. Faint stars in the rarest of predictable astro- pernican theory perhaps, but a binary systems had been de- nomical phenomena. They mysterious inference when at tected for over a century by occur in a pattern that repeats their most intrepid his succes- either astrometry of the visi- every 243 years, with pairs of sors were preoccupied with ble star, or Doppler velocity transits eight years apart sepa- our solar system. In fact, Jo- determinations from absorp- rated by long gaps of 121.5 hannes Kepler (1571-1630) tion lines in the spectrum of years and 105.5 years. Before wrote to Galileo relieved (“You have freed me from the (Continued on page 8)

AIAA Houston Section Horizons January / February 2012 Page 7 Page 8

(Continued from page 7) nus transit observations, what These concerns explain why Kepler-22b visual components (the spec- were the odds of detecting a pursuit of photometric obser- trum of the brighter star or of transit at another star? Like vation of planetary transits the unresolved combined waiting for a particular volca- was viewed initially by many light). Both methods were no to erupt? And how con- with skepticism. But while it naturally enough expanded to stant is the light of a star or is not easy to explain away all searches for planets which even that of our Sun? Those early concerns about the Kep- were large enough to cause who have worked with solar ler Observatory with this brief visible stars to revolve about power might use the rule of survey article, explanation for system centers of mass. thumb value of 1,370 watts some stated concerns can be

per square meter for solar flux provided. In passing, we note The Doppler detection of in vacuum at a distance of one it fortunate that Borucki’s pro planets is now well known, Astronomical Unit (AU). But -photometric arguments pre- especially for its ability to examining this “constant”, vailed. Otherwise space trans- detect very large planets close how steady or accurate is it? it observing would have been to their primaries. There is Could it be 10 watts per left entirely to the European also much discussion about square meter higher or lower Space Agency project CO- the difficulty of detecting in another reference book or ROT. This was the first such Earth-like planets by the same six months ago? If so, is this (and less sensitive) space ob- technique – especially acquir- because of short solar cycles servatory to go on station, ing them visually. Astrono- or the Earth’s slightly ellipti- launched 27 December 2006, mers and engineers are usual- cal orbit? What was the sensi- more than two years prior to ly confronted with the issue of tivity needed to detect a plan- the Kepler launch of March a habitable planet’s relative et? We are aware of convec- 2009. Although COROT faintness so near a Sun-like tive processes on our Sun’s made several large planet star – orders of magnitude surface as well as flares from transit finds prior to Kepler, it fainter than the star – in the our Sun streaming far out in was not the first to produce visible or portions of space. Stellar features are also such discoveries. Some Dop- the spectrum. Even with the obscured by turbulence. pler-discovered “super- best optics a star is difficult to Would planetary transits share Jupiters” were later observed resolve into a pinpoint. The the same fate? And finally, transiting their stars, provid- could enough parallel sam- ing confirmation for the de- halo surrounding stars in pho- tographs is a harmonic aberra- pling of stars be done to allow tection approach. tion known as an Airy disk. any odds for success in a Additionally, it was suspected spacecraft’s mission lifetime? Just as with Doppler tech- that zodiacal dust in the solar niques, Jupiter-sized planets system could obscure Earth Photos of the Mercury and are more easily detected in from view by astronomers Venus transits illustrate other transit than terrestrial planets viewing from planets about problems. While the Venus in habitable zones, especially other stars. If these stars had image is clear, that of Mercu- if the extra-solar Jupiters are planets, would they not have ry is dominated by sunspots. located closer to their prima- zodiacal dust too? How the sunspots affect pho- ries than radii for habitability tometric measurements is not criteria allow (shorter period The Transit Debate entirely clear, but perhaps orbits and more frequent stellar and planetary rotational transits). If the Sun or a simi- Since planets are not bright rates can be discerned; other- lar star’s disk is uniformly compared to stars, could the wise a means of spectral fil- luminous, then passage of a approach to the problem be tering would be required. Jupiter or an Earth in front of turned inside out? Could plan- What’s more, stars have “limb it reduces the light by 1/100th ets subtract sufficiently from darkening.” As seen from a or 1/10,000th respectively. To stellar brightness to be detect- distance they are brightest at distinguish that an Earth sized ed? Could you distinguish an their centers. For this issue, object had transited in front of exoplanet from a sunspot (or a the plot of transits seems to a star, however, it would re- show a transition to the star’s quire greater sensitivity than “star ” in this case)? If th Earth observers had to wait center reaching a light intensi- 1/10,000 or 100 parts per for 130-year intervals for Ve- ty plateau. (Continued on page 9)

AIAA Houston Section Horizons January / February 2012 Page 8 Page 9

(Continued from page 8) Earth save that it would be The spacecraft has a 12- million (ppm). Kepler’s sensi- possible to confirm existence degree diameter field of view Kepler-22b tivity goal was set at 24 ppm more quickly with its more (FOV). Of this, 105-deg2 is of and to date it has demonstrat- frequent passage. Were Jupi- science quality. The photom- ed 84 ppm. Do Doppler de- ter to pass in front of the Sun, eter provides soft rather than tected Jupiter-sized planets it would extinguish more sharp focus for better pho- have moons? Kepler might light, but at its further dis- tometry in the visual and near eventually spot such bodies tance (5.2 AU), the viewing infrared range. The mission with secondary shallower angle based on the Sun as a goal is a combined differen- preceding or trailing extinc- target would be about 0.1 tial photometric precision of tion dips. Target sensitivity degree; follow-ups would 20 ppm for visual magnitude might allow identification of come nearly twelve years m(V) =12 solar-like stars and Mars or Ganymede-sized bod- apart. 6.5-hour integration, though ies (Ganymede is a Galilean the observations so far fall satellite of Jupiter.), but Using once again Earth and short of this objective (see demonstrated capability illus- Sun based model, how long Performance). trates how difficult this detec- would a planetary transit last tion will be. at a distance of one AU with An Earth-like transit produc- a one-year period? Approxi- es a brightness change of 84 The likelihood of observing a mately the time to travel 1.4 ppm and lasts for 13 hours transit depends on the size of million kilometers at thirty when it crosses the center of the stellar disk and the dis- kilometers per second: less the star. The focal plane of tance between the planet and than 13 hours. the spacecraft's camera is the star. Let us assume a star made up of 42 CCDs at 2,200 of the same mass and thermal × 1,024 pixels, the largest flux as the Sun with planets The Spacecraft as a Cam- camera launched into space similar to the Sun’s aligned era and Recorder with a resolution of 95 mega- for transit in an observer’s pixels. The array is cooled by line of sight: an “Earth,” a Kepler launched 07 March heat pipes connected to an “Venus” and a “Jupiter.” The 2009 from Space Launch external radiator. The CCDs 700,000-kilometer radius of Complex 17-B Cape Canav- are read out every six seconds the Sun (and this star) at one eral Air Force Station Launch (to limit saturation) and co- AU (150 million kilometers) on board a Delta II (7925- added on board for 30 results in a width of 0.5 de- 10L) for a mission of at least minutes. At launch Kepler gree or one chance in 180 to 3.5 years of which nearly 3 had the highest data rate of detect the “Earth” from anoth- have already elapsed. Posi- any NASA mission, the 30 er star in space via transit, tioned into an Earth-trailing minute sums of all 95 million based on possible inclination heliocentric orbit with a pixels constitute more data orientations from 0 to 90 de- 372.5 day period, its photo- than can be stored and sent grees. It would take another metric instrumentation oper- back to Earth. So the science two years to verify this with ates at bandwidth between team pre-selected the relevant confirming passes. “Venus” at 400 and 865 nanometers. Its pixels associated with each two thirds the distance would diameter is 0.95 meters (3.1 star of interest, amounting to have a background disk a time feet) with a light collecting about 5% of the pixels. The and a half as wide (0.8 de- area 0.708 square meters. data from these pixels are re- gree) and allow one chance in quantized, compressed and about 112. Perhaps some stored, along with other aux- The Kepler spacecraft, shown transit chords would be so far iliary data, in the on-board 16 in Figure 4, has a mass of short of a diameter that they -gigabyte solid-state recorder. 1,039 kilograms (2,290 might not be useful enough for deriving planetary data; pounds in weight), a 0.95- 2 meter (37.4 inch) aperture, Kepler’s 115-deg field of then the odds would have to view (FOV) gives it a much be reduced accordingly. But and a 1.4-meter (55 inches) primary mirror – one of the higher probability of detect- Venus as viewed in transit ing Earth-like planets than from another star would be no largest mirrors on any tele- more or less detectable than scope outside of Earth orbit. (Continued on page 10)

AIAA Houston Section Horizons January / February 2012 Page 9 Page 10

(Continued from page 9) Performance 29 ppm. Much additional Kepler-22b the Hubble Space Telescope noise indeed appears due to or HST, (FOV ~ 10 deg2). Kepler is working much bet- higher than expected stellar Moreover, Kepler is dedicated ter than any Earth-bound tele- variability (19.5 ppm vs. the to detecting planetary transits, scope, but still short of the assumed 10 ppm) with the while the HST is used to ad- design goals. The objective rest due to instrumental noise dress a wide range of scien- was a combined differential sources slightly larger than tific questions, and rarely photometric precision (CDPP) predicted. Work is ongoing to looks continuously at just one of 20 ppm on a magnitude 12 better understand, and per- star field. HST plus other star for a 6.5-hour integration. haps calibrate out, instrument space and ground observato- This estimate was developed noise. ries with smaller fields of allowing 10 ppm for stellar view continue studies of ob- variability, roughly the value Since the signal from an Earth jects such as Kepler-22b to for the Sun. The obtained -sized planet is so close to the derive orbital elements and accuracy for this observation noise level (only 80 ppm), the features at other spectral has a wide range, depending increased noise means each bandwidths. on the star and position on the individual transit is only a 2.7 focal plane, with a median of (Continued on page 11)

Figure 4 a, b, c & d Kepler Spacecraft Components, Position and Orientation in Space, Field of View (FOV). Image credit for FOV: Software Bisque. Image source: http://spacespin.org/article.php/90438-kepler-captures-first-views. Top left image credit: http://images.brighthub.com/eb/d/ebdbe7834492fb6aecea34aa6e54e16113d37e87_large.jpg. Figure 4c &d: http://kepler.nasa.gov.

AIAA Houston Section Horizons January / February 2012 Page 10 Page 11

(Continued from page 10) earlier Doppler based results slipping outside the range of sigma event, instead of the that presented a host of plan- Kepler visual to near infrared Kepler-22b intended 4 sigma. This, in ets of Jupiter’s mass or more, photometry (Figure 7). In turn, means more transits the Kepler candidate results some cases the distinction must be observed to be sure for planets have thus far between Jupiter and larger of a detection. Recent esti- turned up many more Nep- planets is disregarded. The mates indicate a 7-8 year mis- tune-sized planets. More su- more massive planets do not sion, as opposed to the 3.5 per-Earths are turning up than vary much in diameter unless years planned, would be need- “Jupiters.” Even Earth-sized age and location with respect ed to find all transiting Earth- candidates are about 40% as to their primary stars are tak- sized planets. The spacecraft frequent as the Jupiters de- en into account. has enough fuel for such a spite their near burial in back- mission, but there is no fund- ground noise (Figure 5). Among the first 36 Kepler ing for it so far. planetary confirmations, Kep- For purposes of presentation, ler-22b stands out for its long Of the approximately half- Kepler investigators last De- period (289.9 days) vs. peri- million stars in Kepler's field cember divided their results ods of less than one day of view, around 150,000 stars thus far into five principal (Kepler-10b) to 120 days in were selected for observation, planetary size classes: Earth, the first 21 systems, and tem- to be observed simultaneous- Super-Earth, Neptune-sized, peratures are no lower than ly, with the spacecraft meas- Jupiter and Super-Jupiter size. 400 degrees Kelvin – with uring variations in their Also the description of stars one notable exception. brightness every 30 minutes. has been normalized in terms Among these first 22 star sys- This provides a better chance of surface temperature, leav- tems are several multi-planet for seeing a transit. In addi- ing issues of mass, luminosity systems: one with 6 planets tion, the 1-in-215 probability and radiative peak matters for (Kepler-11); one with 5 means that if 100% of stars audiences to mull later. When (Kepler-20); two with 3 observed had the same diame- results for temperature in Fig- (Kepler-9 and 18) and two ter as the Sun, and each had ure 6 are compared with stel- with 2 planets (Kepler-9 and one Earth-like terrestrial plan- lar classifications, it can be 10). Kepler-20e possesses the et in an orbit identical to that seen that lower-temperature smallest diameter (0.868 of the Earth, Kepler would stars are considerably less times Earth’s radius) with find about 465; but if only luminous than stars like the Kepler-20f in second place 10% of stars observed were Sun. They cannot be seen with a radius slightly larger such, then it would find about over distances as great even than Earth’s (1.034 – see Fig- 46. The mission is well suited though M stars are known to ure 8), but the two planets to determine the frequency of be more numerous than G- possess effective temperatures Earth-like planets orbiting types. Lower temperature star of 1,040 and 705 degrees Kel- other stars. radii fall off significantly as (Continued on page 12) well. But even if stellar radii Kepler Results and surface areas were the same, according to black body As the cover illustration col- radiation theory and Wien’s lage indicates, Kepler results law the spectral flux peak trend toward discovering wavelength is inversely pro- planets with longer and longer portional to surface tempera- periods. For an alien Kepler ture. MAX * TEFF = constant). spacecraft looking for Earth Given that the Sun’s effective transiting the Sun, three trans- surface temperature is 5,780 its would require between two degrees Kelvin and its peak and three years. Kepler-22b is emission wavelength is 501 on the inner edge of a habita- nanometers or 5,010 ang- bility zone of a star only stroms, a sphere of the same slightly fainter (and less mas- size of half the temperature sive) than the Sun with a peri- would emit at a peak wave- od of 290 days. Despite the length 1,002 nanometers - Figure 5: Number of planet candidates. Image credit: NASA.

AIAA Houston Section Horizons January / February 2012 Page 11 Page 12

(Continued from page 11) Kepler-22b vin respectively. The “notable exception” mentioned above is Kepler- 16b which orbits around tight, but relatively faint stellar binaries in 228 days with a temperature esti- mated between 170 and 200 degrees Kelvin (-154 to -100 Fahrenheit). The binaries eclipse and transit each other as well. The first three planets in the Kepler observatory numbering system were actu- ally identified with ground telescopes and confirmed by the Kepler spacecraft as part of its in-flight calibration and test. Figure 7: Planet Sizes Relative to Earth. Image credit: NASA.

During the January American Aeronautical Society confer- ence in Austin, two more two planets smaller but hotter February. planets orbiting binary stars than Earth and three planets were added to the Kepler list closely orbiting a faint M- The orbiting Spitzer Infrared (Kepler-34b and Kepler-35b), type dwarf similar to Bar- Space Telescope has been the nard’s Star. Should the Kepler and stars identified with Kep- chief space observatory team follow the pattern of ler objects of interests (KOI) providing backup to the Kep- resulted in planet identifica- previous years, they might tions by ground programs: provide further updates in (Continued on page 13)

Figure 6: Beside Stellar Temperature, Planet Discoveries Affected by Stellar Numbers, Luminosity & Radius. Image credits: NASA.

AIAA Houston Section Horizons January / February 2012 Page 12 Page 13

Kepler-22b

(Continued from page 12) tion bands (ozone, water va- or a diminutive, warm Neptune. ler Observatory. The Hubble por, methane), distinguishing But based on perceived discov- Space Telescope (HST), Earth-like planets from ex- ery trends, Kepler-22b could though it has an aperture of oplanets better described as very well be called Harbinger. 2.4 meters, had its photometer lifeless rocks or bottomless traded out for other instru- wells of gas. The Kepler team ments on the first space shut- continues work on its 3.5-year tle servicing flight and HST mission, finding what fraction has limited infrared capabil- of stars in our galaxy are ity. But its successor, the hosts for Earth-like planets in James Webb Space Telescope habitable zones. And there is has both wide aperture and some chance that the mission highly sensitive infrared in- can be extended to as long as strumentation. Besides look- eight years with the benefits ing at nearby stars for non- of identifying exoplanets of transiting planets, this yet-to- longer and longer periods. In be-launched telescope might the meantime, with closer be able to detect planetary study, Kepler-22b could re- infrared atmospheric absorp- veal itself to be a super-Earth

Figure 8: Flux Normalized to Solar Peak vs. Wavelength. Image credit: Wes Kelly.

AIAA Houston Section Horizons January / February 2012 Page 13 Page 14

Cassini A Peek at Cassini after Seven Years in Orbit DANIEL R. ADAMO, ASTRODYNAMICS CONSULTANT

After becoming humankind's vival and mission success. plane. Cassini's as-flown and first artificial satellite of Sat- Both ring material and planned inclination is plotted urn on 1 July 2004, the Cassi- Saturn's retinue of major in Figure 1. ni orbiter shared headlines moons lie within a few de- 1 1The most highly inclined with its companion spacecraft grees of this plane . Conse- When Cassini inclination is major moons of Saturn are Huygens until the latter quently, the distances from nearly zero, encounters with Mimas (inclination of 1.572°) reached the surface of Saturn at which Cassini cross- moons other than Titan are and Iapetus (inclination of Saturn's largest moon Titan es the equatorial plane must practical. During close ap- 7.489°). Cassini generally on 14 January 2005. Since be chosen with care to avoid proaches to Enceladus, Cassi- orbits between these two then, Cassini has continued to catastrophic collisions and to ni has determined this moon moons, whose mean distances observe Saturn, its rings, its obtain close-up observations is continually spewing briny from Saturn are 185,540 km moons, and its magneto- of major moons. Further- ice from its south polar re- and 3,560,840 km, respective- sphere. Mission status, to- more, one of the nodes must gion, as depicted in Figure 2. ly. All orbit and trajectory gether with a wealth of im- never stray very far from data supplied in this article agery and other discoveries 1,221,870 km, the mean dis- From a perspective near are obtained from Jet Propul- enabled by these observa- tance of Saturn's largest moon Saturn's equator, major moons sion Laboratory's (JPL's) Ho- tions, can be accessed at Titan from the planet's center. can undergo mutual transits rizons ephemeris computation http://saturn.jpl.nasa.gov/ Only Titan has sufficient per the Figure 3 Cassini im- system (accessible at http:// home/index.cfm. mass to provide gravity as- age. These geometries are ssd.jpl.nasa.gov/?horizons). sists making Cassini's tour much more likely to arise at Trajectory design strategy possible with the orbiter's lower orbit inclinations. In supporting Cassini's tour of limited propulsive capability. addition to their aesthetic ap- the Saturn system is driven by peal, images of such transits two astrodynamic precepts. The second precept relating to contribute to improved accu- First, node placement with Cassini tour strategy is the racy associated with the respect to Saturn's equatorial orbiter's inclination with re- moons' ephemerides. plane is critical to orbiter sur- spect to Saturn's equatorial (Continued on page 15)

Figure 1. Cassini inclination with respect to Saturn's equatorial plane from Saturn orbit insertion in 2004 until planned mission termination in 2017. Each increment in inclination results from a Titan gravity assist.

AIAA Houston Section Horizons January / February 2012 Page 14 Page 15

Cassini

Figure 2. Cassini imaged briny ice plumes near the south pole of Saturn's moon Enceladus on 23 February 2010. Image PIA11688 credit NASA/JPL/ Space Science Institute (SSI).

(Continued from page 14) As the year 2011 draws to a Figures 4, 5, 6 and 7 appear The Figure 3 perspective near close, Figure 1 indicates Cas- on the following two pages. Saturn's equatorial plane pro- sini is about to end an extend- vides a nearly edge-on and ed period of low inclination highly foreshortened view of observations. This orbit ge- the planet's rings. In contrast, ometry enables a Dione en- Figure 4 is an example of counter on 12 December, fol- perspective from well south lowed by a Titan encounter of Saturn's equator. Observa- the next day, as illustrated in tions of polar regions and Figure 5. The Dione encoun- most ring dynamics are there- ter is plotted relative to Dione fore only practical with Cas- in Figure 6, and the Titan sini's orbit at higher inclina- encounter is plotted relative to tions. Titan in Figure 7. Figure 3. Mimas is seen transit- ing Dione from Cassini on 3 July 2006. Saturn's rings disap- pear into the planet's shadow at bottom. When this image was obtained, Cassini was located just "above" the rings' plane at 0.5° north latitude with respect to Saturn's equator. Because Mimas was located between Cassini and Saturn at this time, its nightside was only illuminat- ed by starlight. In contrast, Dio- ne was located across Saturn and its rings from Cassini, and its nightside was illuminated by reflected sunlight from the planet's dayside. Image PIA08228 credit NASA/JPL/ SSI.

AIAA Houston Section Horizons January / February 2012 Page 15 Page 16

Cassini

Figure 4. Cassini obtained this true color Saturn mosaic on 6 October 2004 from 18° south lati- tude. Note Saturn's shadow on the rings, the rings' shadow on Saturn, and the blue tint in Saturn's atmosphere at high northern latitudes during local winter. These are features difficult or impossible to view from Earth. Image PIA06193 credit NASA/JPL/SSI.

Figure 5. Mid-December 2011 Cassini encounters with moons Dione and Titan are plotted with respect to Saturn in the planet's equatorial plane. Although the Dione encounter has little effect on Cassini's orbit, the Titan encounter noticeably raises apochrone (Cassini's maximum distance from Saturn). Image credit: Daniel R. Adamo.

AIAA Houston Section Horizons January / February 2012 Page 16 Page 17

Figure 6. The "D3" Dione encounter is plotted relative to Dione in that Cassini moon's equatorial plane (parallel to that of Saturn) in nearly the same inertial orientation as Figure 5. Cas- sini's trajectory is indistinguishable from a straight line, indicating Dione exerts very little gravity perturbation, even with Cassini's periapsis height targeted at only 99 km. Image credit: Daniel R. Adamo.

Figure 7. The "T79" Titan encounter is plotted relative to Titan in that moon's equatorial plane (parallel to that of Saturn) in nearly the same inertial orientation as Figure 5. Be- cause Cassini periapsis is over the trailing hemisphere of Titan in its Saturn orbit, angular momentum is transferred from the moon to the or- biter, increasing its apochrone. This transfer is evident as a small devia- tion in Cassini's heading in the direc- tion toward Titan, resulting in greater speed with respect to Saturn immedi- ately after the encounter than imme- diately before it. Since Titan periap- sis falls very near Titan's equator, low inclination with respect to Saturn's equator is preserved throughout the Titan encounter. Im- age credit: Daniel R. Adamo.

AIAA Houston Section Horizons January / February 2012 Page 17 Page 18

Dinner Meeting Sustainable Use of Space Through Orbital Debris Control by Nicholas L. Johnson, NASA DOUGLAS YAZELL, EDITOR

A grateful crowd enjoyed this lowing details are presented wide variety of U.S. government dinner meeting presentation at from the publicity flyer: space endeavors. Mr. Johnson NASA/JSC Gilruth Center on has served as a noncommis- November 29, 2011. Nicholas L. Johnson is Chief sioned officer in the U.S. Air Scientist for Orbital Debris at Force and as an officer in the Journalist Mark Carreau pub- NASA/JSC. As the agency U.S. Navy. He is the recipient of lished an article in an aero- authority on orbital debris, he several military awards, includ- space periodical within a few is responsible for defining the ing the Air Force Commenda- days after this event. AIAA debris environment, present tion Medal. members can obtain details and future, and for designing about that article via AIAA operational techniques by Mr. Johnson is a Distinguished Daily Launch, a daily email which crewed and robotic Alumnus from the University of news summary. That email spacecraft may protect them- Memphis. He is a member of the note was sent to subscribing selves from orbital debris, as International Academy of Astro- AIAA members not long after well as minimize future nautics and an Associate Fellow this event. At the bottom of growth of the orbital debris of AIAA. Mr. Johnson is inter- each of those email notes is environment. Mr. Johnson nationally recognized as an au- an “archive” link, so AIAA also serves and the head of thority on orbital debris and members can follow that link the U.S. delegation to the foreign space systems. He has to find more about Mr. Car- Inter-Agency Space Debris authored eighteen books and reau’s article. As I write this Coordination, and as the U.S. more than 200 papers on these article, I am “not allowed” expert on orbital debris to the topics. access to that archive, perhaps United Nations. due to recent AIAA web site updates (“under construc- Prior to his joining NASA, tion”). I recorded the audio on Mr. Johnson served as adviso- my iPad in case readers would ry scientist for Teledyne like to use those files: editor- Brown Engineering, Inc., and in-chief[at]aiaa-houston.org. principal scientist for Kaman Sciences Corporation. At both For this short article, the fol- companies, he supported a

Right: Nicholas L. John- son, NASA Chief Scien- tist for Orbital Debris, NASA/JSC. Image cred- it: AIAA publicity flyer.

AIAA Houston Section Horizons January / February 2012 Page 18 Page 19

1940 Air Terminal Museum at Hobby Airport Museum An AIAA Historic Aerospace Site DOUGLAS YAZELL, EDITOR

Above: The museum in August of 2010. Image credit: Doug- las Yazell

1940 Air Terminal Museum Wings & Wheels attracted a 8325 Travelair Street small but enthusiastic crowd one day soon as more build- Houston, Texas 77061 on Saturday, December 17, ing restoration is completed. (713) 454-1940 2011. One of the main attrac- (Image credits: D. Yazell.) www.1940airterminal.org tions of this month’s event was plane spotting, and inter- Muse Air was a non-smoking ested visitors were driven airline I appreciated early in A bimonthly column about the around the airport runways my career, but some of my museum. with photography in mind. coworkers found it very diffi- The related web site is: cult to endure non-smoking Left: A framed poster at the flights. When we returned to museum. Image credit: Doug- www.houstonspotters.net work in Downey, California, they smoked at their desks las Yazell. The author Mary Coleman- and everywhere in the work- Woolslayer was a visitor this place, a practice that contin- at this month’s Wings & ued until sometime around Wheels, with her excellent 1988 to 1992. TranStar Air- children’s book, A Biplane lines, a part of Southwest Air- and His Boy. lines, took over Muse Air and continued the non-smoking The Hartzell propeller above tradition. The TranStar jet in two photographs highlights image is from a postcard at a black and white museum the museum. (Image credits: photograph, as well as the old D. Yazell.) brick walls that will be hidden Keep an eye on the museum’s web site to see what is com- Left: From 8 to 80 years of ing up in 2012, especially with the monthly Wings & age, readers will like this Wheels lunchtime programs book. It is aimed at the young- on the third Saturday of most er end of that age range, and months (March 17, 2012, and it is beautifully illustrated. April 21, 2012). Image credit: A postcard used for book publicity. Until next issue, Happy Land- ings!

See www.tigermothpublications.com for more information about A Biplane and Her Boy.

AIAA Houston Section Horizons January / February 2012 Page 19 Page 20

New SPACE Isle of Man - An Excellent Space for Space SHEN GE, CONTRIBUTOR

Nestled between the islands there are only about 30 people existing favorable economic of Ireland and Great Britain on the island actively in- conditions and strong govern- SPACE: Scientific Prepartory floating on the frequently cold volved in the space industry. ment support. The Isle of Man Academy for Cosmic Explorers. and stormy Irish Sea lies a has long been recognized as a verdant isle known as the Isle Yet, the Isle of Man was global finance center. In re- of Man. Known in its native named the fifth most likely cent years, the attention has Manx Gaelic language as nation to next reach the moon expanded to include more "Ellan Vannin" where "ellan" in 2010. In October of 2010, tangible industries, notably means island in Gaelic, the it played host to the Google aerospace. The Isle of Man island has been continuously Lunar X Prize and became an government created the Office inhabited since before 6500 annual sponsor of the X Prize. of Space Commerce via the BC. Never incorporated into The Google Lunar X Prize Department of Economic De- the Roman Empire or later contestant Odyssey Moon was velopment headed by Tim Great Britain, its status as a established on the island. In Craine to facilitate the support self-governing state continues January 2011, two research and collaboration between the today. space stations owned by the local government and any new space company Excalibur international space entrepre- At first glance, an island with Almaz arrived on the island neur willing to establish a a population less than 90,000 and were kept at an aircraft presence there. people and an area less than hangar at the airfield at the 230 square miles may seem former Jurby Royal Air Force My December 2011 trip with the most unlikely place for base located near the northern my business partner Virgiliu aerospace development. In- parish of Jurby, in a town (Virgil) Pop, a space lawyer deed, according to South Afri- with less than 700 residents. from Romania, to the Isle of Below: Coastline on a can expat and aerospace con- Man was as pleasant as pre- December dawn. Image sultant Carla Sharpe, current- This flourishing energy is due dicted by the promotional credit: Shen Ge. ly living on the Isle of Man, to a combination of pre- materials on the Isle of Man website www.spaceisle.com. The pleasant stay was also predicted in correspondence with Christopher Stott, an Isle of Man native and a space entrepreneur who currently lives in Houston with his as- tronaut wife Nicole Stott. Virgil and I were on the Isle of Man for a week to scout potential venues for our sum- mer 2012 space conference and to obtain government and industry support for our com- pany called the Scientific Pre- paratory Academy for Cosmic Explorers (SPACE) to be es- tablished there.

Despite a shaky start with half a day of delayed flights due to persistent storms, we man- aged to eventually land on the Isle of Man in one piece. Our local legal contact Ranulf

AIAA Houston Section Horizons January / February 2012 Page 20 Page 21

Lucas provided us with a light curious while Mr. Jarrett helped build the local astrono- New SPACE afternoon lunch before we all was eager to help. We met my society's observatory. De- dashed off to the government Kurt Roosen, an entrepre- spite the rainy dreary weather, office. The first person we neur who had aspirations typical of the Isle of Man in met was Tim Craine, a mod- similar to ours, though his winter, we found that the ob- SPACE: Scientific Prepartory est man who showed genuine interest was in IT instead of servatory itself was well- Academy for Cosmic Explorers. passion for space. Despite his space. He has founded the stocked and warm. The busy schedule, he spent an Manx Education Founda- cloudy sky didn’t dull our hour in person with us in his tion (MEF), an organization sunny spirits as we settled government office’s meeting dedicated to creating the down, chatting about the ob- room and answered all our first IT university on the servatory and space in gen- questions in a patient and Isle of Man, with its loca- eral. straightforward manner. tion at the decaying, ancient When we discussed our need Castle Mona, which will be In conclusion, the Isle of Man for government support for renovated by September is proving to be an excellent our venture, he was quick to 2012. space for space. Our trip was state that he can provide an a resounding success and we assistant to overlook our busi- The last government offi- are happy to inform you that ness plan as soon as we can cial we met was the acting our space conference is hap- send him one. On a quirky Attorney General who allo- pening on the Isle of Man on note, he seems to have a fasci- cated several hours to sit July 9-10, 2012 at the Sefton nation with China given that down with us and go Hotel. You can register using he has more than 20 Chinese through our company's arti- this web site: ties and was wearing one dec- cles of association and by- orated with Chinese writing laws. She pointed out flaws http://spaceconf.com/ when we met with him. and answered all of our questions. A bit of advice: Don't visit the At the same meeting sat Me- Isle of Man in December if Shell Berry, an energetic lady The last few days conclud- you can avoid it, since Mother originally from Houston who ed with tours of possible Nature will offer you a cold migrated to the Isle of Man 14 conference venues on the reception. Thankfully, the years ago and decided to stay island. The seaside views local citizens will always of- permanently with a family. were spectacular and we fer you a warm welcome. The She is now an event organizer will select a venue with that SPACE conference in July for the Department of Educa- scenery in mind. These in- 2012 will assuredly receive a tion. She is also in charge of cluded the five-star Sefton warm reception from both the the Conrad Foundation on the Hotel, the government con- Mother Nature and the resi- Isle of Man, an international Below: Nunnery grounds on a ference venue Villa Marina, dents of the Isle of Man. inventor's challenge for high December afternoon. Image the Claremont Hotel, the school students. Through the credit: Shen Ge. Nunnery, and the Department of Education, she Manx Museum. The provided the buses and per- Nunnery, despite its sonnel for the 2011 Excalibur limited indoor seating, Almaz opening exhibition attracted us immediate- presenting their planned space ly as an apt location stations. for a dinner social thanks to its verdant The next few days passed by outdoor space. with talks at various locations throughout Douglas with local At the Manx Museum, entrepreneurs. At the Interna- we coincidentally met tional Institute of Space Com- an older amateur as- merce (IISC), we sat down tronomer who worked with Chris Hall, an entrepre- at there. His enthusi- neur who formerly worked for asm was infectious, Manx Telecom, and Ian Jar- and he led us to the rett, the CFO of Mansat LLC. countryside where he Mr. Hall was respectful and

AIAA Houston Section Horizons January / February 2012 Page 21

Page 22

3AF MP Biodiversity and Light Pollution PHILIPPE MAIRET AND JEAN-LUC CHANEL, 3AF MP

In 2010, declared of a national map of natural distinguishing day from night, 3AF MP: "International Year of Biodi- and semi-natural habitats, and trips that take place usual- l’Association Aeronautique et versity" by the United Na- with a planned completion ly at night can not be guaran- Astronautique de France, Midi tions, international commit- date of 2018." teed. In addition, reproductive -Pyrenees chapter, ments and actions were taken cycles are modified and un- www.3af-mp.fr. in Nagoya (Japan) to stem the Overseas, in French- fortunately upset. Our French sister section is loss of biodiversity in the administered territories out- 3AF MP. See our web page at world. This is a real challenge side of the European conti- Articles about light pollution www.aiaa-houston.org. Click to consider, one that is essen- nent (Outre-Mer in French) have been published recently on technical committees, Inter- tial to life on Earth, like na- "regions that host 3,500 plant in 3AF journals: la Gazette national Space Activities Com- tional and international poli- species and 400 vertebrate 3AF MP No. 16 (March- mittee (ISAC). The ISAC is cies concerning global warm- animals unique to the world," August 2009) and No. 18 chaired by Ludmila Dmitriev- ing, and one that if not ad- the French government (January-April 2010), and Odier. An update to the 3AF dressed, would generate a cost "conducts a survey of plant 3AF La Lettre (The Letter) MP organization chart is on equivalent to 7% of global species harvested for tradi- No. 8 (October 2009). Presen- page 27 of our last issue. Gross Domestic Product tional use." It will "open a tations on the subject took (GDP) by 2050. specific service to mobilize place in the recent past in patronage in favor of biodi- Fleurance, France in the Gers In France, the Ministry of versity." region in 2009 (as part of the Ecology presented, on Thurs- International Year of Astrono- day, May 19, 2011, its plan to In this struggle for biodiversi- my), in Pibrac, France in halt biodiversity loss in recent ty, let us not forget to fight Haute-Garonne region in years. This effort must be also, simultaneously, against 2010, at La Geode in Paris, integrated into all public poli- light pollution due in particu- France in 2010, and during cies in all sectors: water, soil, lar to the sometimes excessive the event "Ciel en climate, energy, agriculture, nighttime lighting of cities. Fête" (http://cielenfete.fr/ , the forestry, urban planning... It This type of pollution may second occurrence of this would also be prudent to ex- interfere, on the one hand, event in 2011 in Toulouse, periment with business units with observations of the night France). and management of collabora- sky dear to astronomers, Below: rana-palustris-5.jpg. tive fishing. This year the whether amateur, semi- What could be the "uphill Image credit: http:// French government plans to professional and professional, paths" to fight against light www.grenouilles.free.fr/especes/ launch the worksite "Creation and, on the other hand, harm pollution? grenouille_marais.php biodiversity by degrading the • Reduce energy costs while capability of cer- ensuring the safety of per- tain animal and sons and property. Some plant species to studies, including road safety protect against the studies, show a maximum excess of light. lighting of the road is not a Not to mention guarantee to better "identify" that some humans the other vehicle, in that it is may also be af- normally illuminated by its fected by too own light. Moreover, studies much light at show no correlation between night. brightness of such maximum lighting and frequency of With regard to collisions. However, a mini- animal species, mum illumination is essen- the excessive tial to walk normally. It is nighttime bright- also a psychological consid- ness longer allows eration.

AIAA Houston Section Horizons January / February 2012 Page 22 Page 23

• Think twice before setting (www.faaq.org/menucielnoir/ The Defense Meteorological 3AF MP up outdoor lighting, whether memoire_ville_montreal.pdf), Satellite Program (DMSP) public or commercial. prepared by Chloé Legris, at monitors meteorological, (ANPCEN proposes solu- the time a trainee engineer in oceanographic, and solar- tions. It is up to AFE to con- charge of the project ASTRO- terrestrial physics for the sider them and bring together Lab of Mont-Mégantic, was United States Department of an “ad hoc” working group.) presented by the Federation of Defense. Amateur Astronomers of Editor’s note: ANPCEN: Quebec. This public consulta- www.anpcen.fr: Association tion allowed creation of a real Nationale pour la Protection awareness on the part of local du Ciel et de l'Environnement government. Nocturnes, National Associa- tion for the Protection of According to the French mag- heaven and the night environ- azine "Sky and Space" (Ciel ment. AFE: www.afe- et Espace) of December 2011, eclairage.com.fr: Association park officials of Mount Mé- Below: Poppies. Image credit: Française de l'Eclairage, gantic were "coming back to Public domain, Franz Eugen French Association of Light- the frontline of the war" to Köhler, Köhler's Medizinal- ing promote or enforce the regu- Pflanzen. Image source: Wik- lations: for example, Mount ipedia (http:// • Organize awareness cam- Mégantic "defends its heaven- fr.wikipedia.org). paigns. ly heritage."

All this takes time, resources If keeping the label "RICE" and means. can be a challenge, it is worth noting that local initiatives in Recently, there has been dis- France allow cities (of about cussion of "corridors" or 5,000 inhabitants) and villag- "reserves" of dark sky. In the es to obtain the label of Midi-Pyrenees region of "Celestial City" or "Village France, let us note the exist- Etoile" (Editor’s note: Village ence of the "Black Triangle with a Starry Night Sky : du Quercy" and the proposed http://www.villes-et-villages- first RICE ("International etoiles.fr ), since the event Dark Sky Reserve") in Europe "The Day of the Night" was that would be created around recently created, and in 1992 the Pic du Midi (supported by the United Nations Education- the association PIRENE). al, Scientific and Cultural Organization (UNESCO) de- RICE was awarded for the clared the night sky to be the first time in the world in Que- worldwide heritage of man- bec, Canada in the Parc du kind. Mont-Mégantic, by the Inter- national Dark Sky Associa- It is not unthinkable that in tion (IDSA). the future it will be possible to observe (or measure) light For a related story, let us re- pollution with space assets, call, "Night Lighting and other than the International Light Pollution", filed as part Space Station (ISS) and of a public consultation for DMSP satellites, and compare the revision of the Master the results with observations Plan of the City of Montreal, and measurements from the Quebec. ground.

This document Editor’s note (Wikipedia):

AIAA Houston Section Horizons January / February 2012 Page 23 Page 24

3AF MP The Right Stuff at the Cinémathèque de Toulouse PHILIPPE MAIRET, 3AF MP

3AF MP: Wednesday, November 30, programmed at the Ciné- http:// l’Association Aeronautique et 2011, moviegoers rediscov- mathèque de Toulouse, but www.lacinemathequedetoulou Astronautique de France, Midi ered, or discovered, perhaps, also at the Cité de l'Espace, se.com/ -Pyrenees chapter, the movie masterpiece The until a date not yet specified www.3af-mp.fr. Right Stuff by director Philip in May 2012. www.cite-espace.com Our French sister section is Kaufman, dedicated to early 3AF MP. See our web page at American spaceflight. First Price: 6.50 € www.aiaa-houston.org. Click released to theaters in 1983, Concessions: € 5.50 on technical committees, Inter- this 3-hour and 15-minute Youth under 18: € 3 national Space Activities Com- epic centered on the Mercury mittee (ISAC). The ISAC is program brought to life the (Tickets are available at the chaired by Ludmila Dmitriev- difficult conquest of the "new Cinémathèque and the Cité de Odier. An update to the 3AF frontier" with intensity, emo- l'Espace.) MP organization chart is on tion, and even poetry, against page 27 of our last issue. a background of competing To find the film series pro- with the Soviets. gram for "The Space Odyssey":

Right: The film festival web The Toulouse Film Archive site provided a preview of the gave moviegoers the go for movie, The Right Stuff. Image launch Wednesday, Novem- credit: www.enjoyspace.com. ber 30, 2011, at 7:30 PM for a special session in the presence of Philippe Perrin, and .

It should be noted that this film screening introduces a series entitled "The Space Odyssey" in partnership with the Centre Nationale d’Etudes Spatiales (CNES) and the Cité de l'Espace in which several space-themed films will be

Right: Film festival infor- mation for the event in Tou- louse, France, November 2011 through a date to be deter- mined in May 2012. Image credit: La Cité de l’Espace.

AIAA Houston Section Horizons January / February 2012 Page 24 Page 25

3AF MP

Far Left: ATV-2 patch. Image credit: ESA (http:// esamultimedia.esa.int/images/atv/ATV2_LOGO_Hi- res.jpg)

Left: ATV-2 approaching ISS. Image credit: ESA (http://www.esa.int/ images/5475346310_db1a344f8a_o.jpg)

A close-up view of the Interna- tional Space Station is featured in this image photographed by an STS-133 crew member on space shuttle Discovery after the station and shuttle began their post- undocking relative separation. Undocking of the two spacecraft occurred at 7 a.m. (EST) on March 7, 2011. Discovery spent eight days, 16 hours, and 46 minutes attached to the orbiting laboratory. Image credit: NASA. Image source: http:// spaceflight.nasa.gov/gallery/ images/shuttle/sts-133/html/ s133e011051.html.

Left: A view of ATV-2 Johannes Kepler as seen from the International Space Station during its launch aboard an Ariane 5 ES- ATV launch vehicle on 16 February 2011. The Expedition 26 crew member aboard the International Space Station who snapped this photograph of the Ariane 5 rocket, barely visible in the far background, just after lift off from Europe's Spaceport in Kourou, French Guiana, and the rest of the crew have a special interest in the occur- rence. ESA's second Automated Transfer Vehicle, Johannes Kepler, was just a short time earlier (21:50 GMT or 18:50 Kourou time on Feb. 16, 2011) launched toward its low orbit destination and eventual link-up with the ISS. The unmanned supply is planned to deliver critical supplies and reboost the space station during its almost four-month mission. The elbow of Cana- darm2 is in the foreground. , Photographer, Astronaut, 16 February 2011, 517837main_iss026e027223_full.jpg. Im- age credit: NASA. Image source: http:// cio.gsfc.nasa.gov/images/content/

AIAA Houston Section Horizons January / February 2012 Page 25 Page 26

Lunch-n-Learn Warp Drives: A Curious History DR. ALBERT A. JACKSON IV

Dr. Albert A. Jackson is Chair In 1966 I went to the World “Warp Factor,” as applied to general exploration of the of the AIAA Houston Section Science Fiction convention in the faster-than-light “warp solar system by spaceship. astrodynamics technical com- Cleveland (the 24th). Gene drive.” Soon the Solar System be- mittee, a Fellow of the British Roddenberry showed the pilot came too small a stage and Interplanetary Society, an for Star Trek, not used, later Warp Drive has to be one of the stars beckoned. It is quite AIAA Associate Fellow, and a fixed up as a two episode en- the oddest histories as a remarkable that SF writers visiting scientist at the Lunar try. “super-science” artifact of showed a comprehensive and Planetary Institute in modern prose science fiction. grasp of what interstellar dis- Houston, Texas. All the SF fans there were The great fathers of modern tances meant. Maybe more enthusiastic about it. Later science fiction (SF), Jules remarkable was an under- Dr. Jackson organized and Gene was in a hallway of the Vern and, especially, H.G. standing the implications of hosted this event with guest hotel with a model of the En- Wells did not concern them- Special Relativity and light as speaker Dr. Harold “Sonny” terprise, kind of an “author’s selves with flight out of the a speed limit, though E. E. White, NASA/JSC. tour”, except, alas, he was solar system. Smith's early Skylark and later alone, no one was talking to Lensman stories show a joy- Technical committee web him. I went up to him and The infusion of spaceflight ous disregard for any such pages: www.aiaa- said, “Gee, I sure recognize into modern SF prose oc- natural speed limits. houston.org. an almost complete nomen- curred early. The basic phys- clature from prose science ics known by Verne and Interstellar distances could be fiction presented in your tele- Wells was transformed by bridged with slower than light play.” Konstantin Tsiolkovsky, Her- technology. Konstantin Tsiol- mann Oberth and Robert H. kovsky first saw this using He said, “You should, I was Goddard into solid engineer- generation starships. This was and am an avid reader of ing physics. This was picked extended to “World ” by modern science fiction up by writers to become an the brilliant British physicist prose.” A few years later I emerging prose entertainment John Desmond Bernal’s 1929 don’t think I could have ap- known as science fiction, SF. work The World, the Flesh Below: A graphic image from proached him through a (One notes that SF, even early and the Devil. our publicity flyer for this crowd of admirers. on, was more than space event. See the figure on the flight.) It was John W. Campbell, next page for details. Image Maybe one of the first super- with a degree in physics from credit: Dr. Harold “Sonny” science terminologies a view- From the 1920s, and especial- Duke University, who laid the White, NASA/JSC. er of Star Trek remembers is ly in the 1930s, there was a (Continued on page 27)

AIAA Houston Section Horizons January / February 2012 Page 26 Page 27

(Continued from page 26) the writers with no scientific similitude. Lunch-n-Learn groundwork for faster than background knew not only light (FTL) technology using about stellar distances but One of the most influential essentially extrapolated Special Relativity. Light as a stories from 1940 to 1950 was curved space time from Ein- limiting speed was a plot an- Isaac Asimov’s Foundation stein’s General theory of Rel- noyance, even though writers Series. The “hyper-drive” was ativity (GR) in his stories continued to extract great used as a standard plot device Islands of Space (1931) and stories from slower-than-light to fix up the problems with The Mightiest Machine travel. keeping timelines running in (1934). I don’t think GR is parallel. Another space-time ever explicit in SF FTL in the After John Campbell became concept was to use multiply 1930’s and 1940’s but it shad- editor of Astounding Science connected topology. ows almost every story that Fiction magazine in 1938, a uses “warp” drives, hyper- greater degree of sophistica- In 1935 Einstein and Rosen drives, jump-drives… the list tion in narrative was intro- revised an idea by Herman is almost endless. By the duced. Campbell was fond of Weyl of using a singularity- 1930s, science fiction writers a method of narrative exposi- free version of the Schwarz- were feeling confined by the tion that eschewed schild solution of the GR solar system. A greater stage, “technobabble”, preferring a equation which they called a Below: A chart from the presenta- the Galaxy, beckoned, and it “just do it” approach to “bridge.” They were not inter- tion. Image credit: Dr. Harold was remarkable that most of achieve a higher level of veri- (Continued on page 28) “Sonny” White, NASA/JSC.

AIAA Houston Section Horizons January / February 2012 Page 27 Page 28

(Continued from page 27) Lunch-n-Learn ested in it as a mode of transport, but wanted to thread it with an electric field and build a model electron. Somehow , by way of some- one who knew the paper, this passed into the culture of SF writers. A terrific description of ‘jumps through hyper- space’ is given by Robert Heinlein in his 1953 novel Starman Jones.

The use of FTL in SF stretch- es from the late 1920’s to the present. Its use was a curious motivator. There was no real physical basis for it in the non -fictional world. The revival of Black Hole physics (first the notion of diving through a that not even one photon of light studied in the 1930s) in the black hole as a portal to dis- could pass through it before it 1960s had inspired SF writers tant realms with the idea of closed. Kip Thorne and his grad- to use them as space-time using a wormhole. Thorne uate students at Caltech turned shortcuts until it became it suggested that Sagan use a the problem around and asked was shown that was a good wormhole in his novel, rather what forms of matter are re- way to get killed! than a black hole. However, if quired to hold a wormhole open wormholes are to be used for permanently, so no pinch-off Then, when writing the novel FTL communication or trans- occurs? The answer is 'exotic' Contact, Carl Sagan Sagan portation, the issue of stability matter, a highly stressed matter, asked Kip Thorne, the Feyn- is an extremely important one. with enormous tensile strengths. man Professor of Physics at In 1962, Wheeler and Fuller Caltech, for advice to help demonstrated that Einstein- On December 13, 2011, the AI- ensure that the method chosen Rosen wormholes are ex- AA Houston Section Astrody- to transport the novel’s hero- tremely unstable, so that if namics Technical Committee ine across the Galaxy would such a wormhole should hap- had Dr. Harold “Sonny” White not be scientifically ludicrous. pen to appear spontaneously it of NASA/JSC present his work Thorne suggested replacing would pinch off so rapidly (Continued on page 29)

From the publicity flyer: Warp Field Mechanics 101 “The goal of timely interstellar flight – to reach other habitable worlds within a human lifespan – cannot be achieved with even the most refined technological applications of accrued physics. The exhaust velocity and propellant mass required when applying the rocket equation, or the power level required for photon momentum transfer, are so high as to fall into the realm of the seemingly impossible. To circumvent these limits, it is desired that new, advantageous, propulsion physics awaits discovery. For example, if it were possible to move a spacecraft using the interactions between the craft and its surrounding space without needing propellant (a space drive), then the energy requirements would drop from exponential to squared functions of trip velocity. If fast- er-than-light travel becomes possible, then the light years spanning star systems become traversa- ble within a human lifespan.” - Marc Mills - Tau Zero Foundation.

Editor’s note: Attendance was 65 or 70 people for this popular event in the Lone Star room at NASA/JSC Gilruth Center. Most of the charts from the presentation are available here: http:// ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20110015936_2011016932.pdf. Related infor- mation: http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20110023492_2011024705.pdf.

AIAA Houston Section Horizons January / February 2012 Page 28 Page 29

(Continued from page 28) the time a graduate student at erties not usually seen in ordi- Lunch-n-Learn on a warp drive. After its in- the University of Wales in Car- nary situations - such as nega- vention as a plot device in SF diff, published a mathematical tive mass or energy densities. in the early 1930’s through description of a spacetime ge- There is not room here to ex- Star Trek an unexpected theo- ometry that embodies the prop- pand on the theory of worm- retical development was pre- erties usually associated in hole or warp travel. The reader sented in the early 1990’s. In science fiction with a ”warp can find a recent exposition in 1994, Miquel Alcubierre, at drive.” In this geometry, a the recent book Time Travel “starship” can appar- and Warp Drives, by Allen ently travel faster Everett and Thomas Roman, Left: Dr. Albert A. Jackson IV. than the speed of University of Chicago, De- Image credit: Douglas Yazell. light, traversing inter- cember 2011. stellar distances of many light years in It has been a long path from an arbitrarily short prose fiction to theoretical con- time – both as meas- structs of FTL travel. A lot of ured by those on the physics needs to be developed, starship, and those at such as an understanding of the destination. One “exotic” matter and physics says ”apparently” aspects of the solutions regard- because the starship ing their stability. Even if all never exceeds the this can be solved, the techno- speed of light as logical construction of warp measured by a local dive starships will present an observer - the basic enormous engineering feat. tenet of Einstein’s special relativity is not violated.

“Exotic matter” is matter that has prop- Left: Dr. Har- old “Sonny” White, NASA/ JSC. Image credits: Doug- las Yazell.

AIAA Houston Section Horizons January / February 2012 Page 29 Page 30

Astrodynamics Phobos-Grunt’s Inexorable Trans-Mars Injection Countdown Clock DANIEL R. ADAMO, ASTRODYNAMICS CONSULTANT

Introduction

Phobos-Grunt, Russia's sample return mission targeting the martian moon Phobos, was to have marked this nation's return to interplanetary spaceflight after a decades-long hiatus. Launched from Baikonur Cosmodrome, Kazakhstan atop a Zenit rocket on 8 November 2011 at 20:16:03 1This actual launch time and UTC1, Phobos-Grunt achieved a nominal Earth parking orbit with apogee/perigee heights of other as-flown events, together 344/204 km2. The initial Figure 1 ground track terminus is annotated "separation of the SC from with all Phobos-Grunt mission the LV". This event occurred 11 min after launch and corresponds to Phobos-Grunt separation planning and performance from the Zenit second stage. specifications cited in this arti- cle, are obtained from Rus- sianSpaceWeb.com unless noted otherwise.

2These heights are in- ferred from USSTRATCOM 2 -line element set (TLE) #4 with epoch 9 November 2011 at 09:33:24 UTC.

Figure 1. This world map illustrates Phobos-Grunt's planned ground track from Earth 3 3Throughout this article, a parking orbit insertion through two trans-Mars injection (TMI) burns . The track is col- "burn" event refers to planned ored red when the spacecraft is in sunlight and black when in Earth's shadow. Broader operation of Phobos-Grunt track segments over South America, labeled "1st EB" and "2nd EB", indicate the two TMI propulsion systems. This is burn arcs. Shaded regions, indicating night on Earth's surface during each TMI burn, are distinct from an "impulse", labeled "1 EB" and "2 EB" near Antarctica. Phobos-Grunt height above Earth in km is which refers to an instantane- annotated in yellow-green with "x" ground track markers. By the time Phobos-Grunt's ous approximation of how one planned trajectory is over Texas post-TMI, the departing spacecraft was to have been about or more burns would affect the half the Moon's distance from Earth. Image credit: RussianSpaceWeb.com. Phobos-Grunt trajectory.

After separation from Zenit, Phobos-Grunt was to have performed a 2-burn TMI to depart Earth orbit and intercept Mars in September 2012. Both TMI burns, together with the initial Mars orbit insertion (MOI) burn, rely on a modified Fregat-MT upper stage known as Flagman for propul- sion. Flagman uses hypergolic propellant and is equipped with drop tanks dedicated to the first TMI burn. After depletion, these tanks are to be left in Earth orbit after the first TMI burn has raised apogee to 4100 km. This event is marked by Figure 1's "Jettisoning of tanks" annotation off the West African coast.

Although telemetry was received from Phobos-Grunt as it passed over Russia an orbit after launch, no transmissions from the spacecraft were detected an orbit later. Tracking in this (Continued on page 31)

AIAA Houston Section Horizons January / February 2012 Page 30 Page 31

(Continued from page 30) timeframe also confirmed the first TMI burn had not occurred. Some relatively minor propulsive Astrodynamics events could be associated with Phobos-Grunt tracking in the interval from 10 to 20 November 2011, but nothing resembling the first TMI burn ever occurred. Meanwhile, limited telemetry was received from the spacecraft over Australia on 22 and 23 November 2011, but no capability to reliably command Phobos-Grunt was ever established after launch. The original parking orbit ultimately decayed on 15 January 2012.

This article will make no attempt to explain why Phobos-Grunt systems were unable to perform

TMI. Rather, the intent here is to first estimate the change-in-velocity capability (vC) of Flag- man. With this vC budget, nominal Phobos-Grunt launch season closure is estimated. Finally, the Earth parking orbit into which Phobos-Grunt actually launched is assessed to estimate the latest possible date on which the planned mission could be recovered. Whereas the launch season is reported to have closed on 20 November 2011, this season was largely irrelevant to mission recovery after 8 November's actual launch. Following this launch, a "no later than" TMI count- down clock was set to expire in only a few days as Phobos-Grunt's Earth parking orbit plane failed to remain adequately aligned with the required Earth departure asymptote bound for Mars.

Consequently, study of hypothetical Phobos-Grunt mission recovery scenarios is highly relevant to any interplanetary transportation architecture requiring a multi-launch campaign prepositioning mass in low Earth orbit (LEO) prior to its departure for an interplanetary destination. The first launch in such a campaign also initiates an Earth departure countdown clock that cannot be slipped later by more than a few days.

Estimated Flagman TMI/MOI Capability

Total Flagman change-in-velocity capability for Phobos-Grunt is defined as the sum of two com- ponents such that vC = v1 + v23. The first component, v1, is generated with propellant from Flagman's drop tanks and applies exclusively to TMI's first burn. After drop tank jettison, v23 capability is applicable to both the second TMI burn and initial MOI. Throughout vC estima- tion, a best-case simplifying assumption is made that all Flagman burns are applied impulsively to maximize vC. This reinforces the "latest possible" pedigree associated with launch season closure and last possible mission recovery estimates presented subsequently.

Data relevant to vC estimation are as follows.

mi1 ≡ total spacecraft mass at Zenit separation and at first TMI burn ignition = 13,500 kg ms1 ≡ depleted Flagman drop tanks mass at jettison = 335 kg mp1 ≡ usable propellant mass in Flagman drop tanks = 3050 kg mp23 ≡ usable propellant mass in Flagman (not including mp1) = 7050 kg ISP ≡ Flagman hypergolic propulsion specific impulse = 333.2 s g ≡ gravitational acceleration at Earth's surface = 0.00980665 km/s2 vX ≡ Flagman hypergolic propulsion exhaust speed = g ISP = 3.268 km/s

The rocket equation then determines both vC components.

v1 = vX Ln{mi1 / (mi1 - mp1)} = 0.837 km/s v23 = vX Ln{(mi1 - mp1 - ms1) / (mi1 - mp1 - ms1 - mp23)} = 3.902 km/s

Summing these components produces vC = 4.739 km/s.

(Continued on page 32)

AIAA Houston Section Horizons January / February 2012 Page 31 Page 32

Astrodynamics (Continued from page 31)

Estimated Phobos-Grunt Launch Season Closure Date

It is essential to recognize the total change-in-velocity requirement vR associated with any Pho- bos-Grunt launch season date assumes no launch has taken place until that date. This require- ment is the sum of two components such that vR = vTMI + vMOI. Because these components are assumed to be instantaneous, the first is computed as a single impulse even though TMI is planned with 2 burns. Since launch on a previous date has not imposed any geometric Earth de-

parture constraints, vTMI is assumed perfectly posigrade. Likewise, vMOI is assumed perfectly retrograde, rendering vR free of all radial and planar steering losses.

A heliocentric elliptic transfer arc connecting Earth and Mars is fundamental to computing vR. 4Additional Phobos-Grunt mis- Heliocentric velocities at the termini of this arc are byproducts of a corresponding Lambert 4 sion planning information, to- boundary value problem solution . Earth-centered speed at the arc's departure terminus is v∞D, gether with a little experimenta- and Mars-centered speed at the arc's arrival terminus is v∞A. tion, reveal the launch season of interest utilizes Type II (long- At TMI, Phobos-Grunt is assumed to be moving in a circular orbit of height HTMI = 274 km. This way) Lambert boundary condi- value is the average of apsis heights previously given for Phobos-Grunt's actual Earth parking 5 tions with heliocentric transfer orbit on 8 November 2011 at 20:16:03 UTC. With the following data , arcs between 180° and 360°. 3 2 µE ≡ Earth's reduced mass = 398,600.44 km /s R ≡ Earth's radius = 6378.136 km 5Physical values for the Earth E rTMI = RE + HTMI = 6652.136 km and Mars provided in this arti- cle are obtained from the Jet patched conic theory leads to an expression for v . Propulsion Laboratory's Hori- TMI zons on-line solar system data and ephemeris computation service at http:// ssd.jpl.nasa.gov/?horizons. Following initial MOI, Phobos-Grunt mission planning calls for the spacecraft to be at periapsis of a Mars-centered elliptic orbit whose apsis heights are HA = 80,000 km and HMOI = 800 km. With the following data,

3 2 µM ≡ Mars's reduced mass = 42,828.3 km /s RM ≡ Mars's radius = 3394 km rMOI = RM + HMOI = 4194 km aMOI = RM + (HA + HMOI) / 2 = 43,794 km

patched conic theory leads to an expression for vMOI.

In practice, a set of Lambert solutions is generated for each launch/TMI/departure date in the Phobos-Grunt season, beginning with 9 November 2011. While solutions in a set share the same Earth departure date and other Lambert boundary conditions, each Mars arrival date is unique. The solution whose Mars arrival date results in the smallest vR for the set is assessed to deter- mine whether or not the minimal vR is less than vC. The latest launch date on which minimal vR < vC is the estimated launch season closure date. Figure 2 summarizes results from this analysis.

The estimated 28 November 2011 launch season closure date inferred from Figure 2 data is 8

(Continued on page 33)

AIAA Houston Section Horizons January / February 2012 Page 32 Page 33

(Continued from page 32) Astrodynamics

Figure 2. The blue curve in this plot chronicles growth in vR as Phobos-Grunt launch date is delayed from its actual occurrence on 8 November 2011. On 29 November 2011, the vR = vTMI + vMOI curve first exceeds the vC limit plotted in gray. Estimated launch sea- son closure is therefore 28 November 2011. For reference, the green curve plots growth in vTMI, and the red curve plots growth in vMOI. days later than that previously cited from a RussianSpaceWeb.com report. This deviation may be due to intentionally optimistic assumptions associated with Figure 2 data. However, Roscosmos head Vladimir Popovkin is quoted as stating on 14 November 2011 that Phobos-Grunt's window for Mars departure would close in early December6. The 28 November 2011 launch season clo- sure estimate may therefore be considered "in the ballpark", particularly if vMOI can be reduced 6Reference Emily Lakdawalla's by techniques such as increasing HA. blog at http:// www.planetary.org/blog/ But the entire discussion of Phobos-Grunt launch season closure is academic, if not intentionally article/00003261/. misleading, in the context of actual launch having occurred on 8 November 2011. As will be demonstrated in the next two sections, that launch imposes a latest mission recovery date well before even 20 November 2011.

Estimated Single-Impulse TMI Latest Mission Recovery Date

The total change-in-velocity requirement vR' associated with Phobos-Grunt mission recovery following actual launch on 8 November 2011 is the sum of two components such that

vR' = vTMI' + vMOI. For a specified TMI date initiating mission recovery, the vMOI component is identical to that required by nominal mission prelaunch planning for that date. But the vTMI' component will generally require steering through the angle  in order to turn the geocentric Pho- bos-Grunt Earth parking orbit plane into one containing the required Earth departure asymptote bound for Mars. Assuming this steering is done simultaneously with the TMI geocentric speed increase (the most propellant-conservative single-impulse strategy), associated vector geometry is illustrated in Figure 3.

(Continued on page 34)

AIAA Houston Section Horizons January / February 2012 Page 33 Page 34

(Continued from page 33) Astrodynamics

Figure 3. This geocentric velocity vector diagram forms a triangle with sides whose lengths are geocentric speeds. The first side (smaller black arrow) has speed in Earth parking orbit vEPO before TMI. The second side (larger black arrow) has speed in the Earth departure hyperbola vTMI immediately after TMI. The third side (red arrow) has the change-in- velocity magnitude vTMI' associated with TMI as computed by the law of cosines. When the steering angle  is zero, vTMI' is simply vTMI minus vEPO, as previously computed for a nominal mission's vTMI.

Computing  is not a trivial process. Regular USSTRATCOM updates to the as-flown Phobos- Grunt trajectory in its Earth parking orbit are processed to determine the spacecraft's angular mo- mentum vector c in geocentric inertial space. Although c is normal to Phobos-Grunt's orbit plane at any instant, excess mass about Earth's equator causes c to precess westward at about 5.4° per day. Meanwhile, asymptotic Earth departure velocity v∞D is slowly changing with time in geo- centric inertial space due to Earth and Mars heliocentric motion. Because it measures the angle between a vector and a plane,  is equivalent to v∞D latitude with respect to the Phobos-Grunt Earth parking orbit plane at a specified mission recovery TMI time. Adopting the sign conven- tion " is positive when v∞D points into the hemisphere whose pole is c", the following equation computes its value7. 7A similar quantity called "" is routinely used in planning International Space Station (ISS) operations, and it has the same sign convention. Of course, this parameter defines The foregoing computational pedigree applies to hypothetical Phobos-Grunt mission recovery c with respect to ISS orbit ele- data summarized in Table 1. From these data, it is evident a single-impulse TMI Phobos-Grunt ments. The only fundamental mission recovery option existed for little more than 3 days after actual launch. difference is the ISS  context replaces v with the Sun's ∞D (Continued on page 35) geocentric position vector.

AIAA Houston Section Horizons January / February 2012 Page 34 Page 35

(Continued from page 34) Astrodynamics

Table 1. Hypothetical Flagman propulsion requirement vR' for single-impulse TMI Phobos- Grunt mission recovery is assessed on TMI dates following actual launch on 8 November 2011. Values for vTMI are included to compare with corresponding vTMI' values because the former assume steering angle  is zero. Since increasing  rapidly inflates vTMI' as mission recovery TMI is postponed, vR' exceeds Flagman propulsive capability vC = 4.739 km/s before 12 November 2011.

Inertial dynamics giving rise to  variations can be visualized by projecting snapshots of the precessing Phobos-Grunt Earth parking orbit plane onto the geocentric celestial sphere, along with variations in the direction of v∞D. Like the Figure 1 Earth map, north is up and south is down in the Figure 4 celestial sphere plot. In this analogy, Figure 1 latitude is replaced by Figure 4 declination with respect to the Earth mean equator of Julian epoch J2000.0. Likewise, Figure 1 longitude is replaced by right ascension with respect to the mean equinox at J2000.0 in Figure 4. Because Figure 4 shows the inside of a celestial sphere rather than Earth's surface, east is left and west is right. Consequently, the Phobos-Grunt orbit plane drifts rightward with time in Figure 4.

Figure 4. Snapshots of the actual Phobos-Grunt Earth parking orbit plane on 9 November 2011 (green line), 11 November 2011 (orange line), and 21 November 2011 (red line) are projected onto the geocentric celestial sphere (truncated at declina- tion magnitudes exceeding 60°) defined by Earth's mean equator and equinox of Julian epoch J2000.0. These snapshots il- lustrate westward precession of the plane with time. In addition, slowly changing Earth asymptotic departure directions for Mars are plotted for 9 November 2011 (green "+"), 11 November 2011 (orange "+"), and 21 November 2011 (red "+"). As- ymptotic departure direction lies closest to the Phobos-Grunt orbit plane on 9 November 2011, shortly after actual launch. Only then are TMI propulsive steering losses due to increasing  negligible. By 11 November 2011, these losses are about to exceed estimated Flagman capability to recover the mission with a single TMI impulse.

(Continued on page 36)

AIAA Houston Section Horizons January / February 2012 Page 35 Page 36

(Continued from page 35) Astrodynamics At the 5.4° per day precession rate, about 5 additional weeks would be required for the 21 No- vember 2011 plane to precess near the plotted asymptotic departure directions in Figure 4. By that time in late December 2011, Earth will have phased too close to Mars opposition for Phobos- Grunt mission recovery with Flagman propulsive capability. Note also the possibility that as- ymptotic departure declination can drift so far north (or south) that it exceeds the orbit plane's northern (or southern) declination limit. Under such geometry, TMI  might never be sufficiently near zero, regardless of orbit plane precession in right ascension.

Estimated Three-Impulse TMI Latest Mission Recovery Date

Now assume Phobos-Grunt could have performed TMI with three impulses. The first impulse would actually be performed with two Flagman burns, the first burn depleting its drop tanks. A four-burn Flagman TMI capability enables a strategy whose total change-in-velocity requirement is vR" . Under this strategy, Phobos-Grunt mission recovery following actual launch on 8 No- vember 2011 is the sum of four components such that vR" = vHA + vNPC + vTMI" + vMOI. The first three components of vR" comprise TMI in the foregoing expression, while the vMOI component is identical to that required by nominal mission prelaunch planning for launch on the recovery date.

The three-impulse TMI takes maximum advantage of two propellant-conserving precepts in as- trodynamics. First, a change in speed is best performed at the fastest possible initial speed. In the TMI context, this entails performing posigrade impulses at perigee. Second, a change in direction is best performed at the slowest possible speed, dictating  be reduced to zero at apogee.

In accord with these precepts, the first "height adjust" impulse vHA is posigrade and raises the assumed initial Earth parking orbit's circular height at 274 km to some minimal apogee radius rA. Since there is no distinct perigee in the initial orbit, the vHA impulse establishes a perigee con- sistent with the required Earth departure hyperbola. The second "plane change" impulse vNPC is performed at rA and achieves  = 0 at the next perigee without any change in speed. The third vTMI" impulse is posigrade and performed at that next perigee, whose 274 km height is unaltered from the original parking orbit. Readers familiar with "anytime" lunar return trajectory planning for the Constellation Program will recognize the three-impulse TMI recovery as a fundamentally similar strategy.

As rA increases with increased vHA, the vNPC required to null a specified  decreases. The downside to this trend is orbit period increases with rA, delaying vTMI" and causing all three TMI components to increase. Consequently, rA is increased no more than necessary to reduce vR" within Flagman's vC = 4.739 km/s.

In assessing the three-impulse TMI, it is important to recognize that the first vHA impulse at time t1 will place rA well above a geostationary orbit's radius, all but halting westward precession of the resulting orbit. Although  will continue to increase after t1, it will do so only during brief near-perigee intervals immediately after t1 and before vTMI" at time t3 and while the Earth depar- ture asymptote drifts slowly northwestward per Figure 4. In a continuing effort to impart maxi- mum possible Phobos-Grunt mission recovery capability,  is therefore frozen at its t1 value dur- ing each assessment.

A second consideration when assessing three-impulse TMI is growth in all but the vNPC compo- nent of vR" during the interval from t1 to t3. But vR" - vNPC = vHA + vTMI" + vMOI is just another way of computing vR in a context specific to three-impulse TMI. To compute vR at a specified t3, a least squares cubic polynomial is fit to all vR points plotted in Figure 2. If t3 is (Continued on page 37)

AIAA Houston Section Horizons January / February 2012 Page 36 Page 37

(Continued from page 36) Astrodynamics expressed as a November 2011 UTC decimal day, the following cubic reproduces all Figure 2 vR values in km/s units to at least 0.001 precision.

* 3 2 vR = 0.00001565741*t3 - 0.00001729571*t3 - 0.00392343*t3 + 4.494745

During each three-impulse TMI assessment, the minimum rA is sought for which * vNPC < vC - vR . At any rA being assessed, t3 is one orbit period after t2. This period is comput- ed assuming perigee height remains at 274 km. Three-impulse TMI assessment results are pre- sented in Table 2.

Table 2. Hypothetical three-impulse TMI Phobos-Grunt mission recovery is assessed for TMI dates following actual launch on 8 November 2011 and loss of single-impulse TMI mis- sion recovery capability three days later. A minimal apogee radius rA is targeted by the first vHA posigrade impulse at time t1 such that vR" does not exceed the previously computed vC = 4.739 km/s Flagman capability. The second vNPC impulse can then null the TMI steering angle  such that the third vTMI" impulse at time t3 is purely posigrade. Values for * vR = vR" - vNPC are from a polynomial approximation to vR data plotted in Figure 2.

Table 2 confirms Flagman's vC constraint imposes a runaway increase in rA in order to decrease * vNPC as  and vR increase with postponed t1 and t3, respectively. To be a viable mission recov- ery option, a three-impulse TMI must be initiated such that t1 is earlier than 18.0 November 2011 UTC. By that time, rA has grown to the point t3 falls after 29 November 2011. As noted in Figure 2's caption, a t3 this late drives vR to exceed vC, and no Flagman capability is available to per- form vNPC.

Conclusion

The Phobos-Grunt mission's failure to achieve TMI serves as an empirical demonstration of the difference between a launch season and the interval in which a mission may be recovered after an otherwise nominal launch into LEO leads to delayed departure for deep space. An inexorable mission recovery countdown clock is running during the delay. In the Phobos-Grunt case, this clock expired 3 to 9 days after actual launch, depending on the number of TMI burns mission managers were willing to perform. This estimated mission recovery interval is but a fraction of the mission's 20-day launch season, even if the season is assumed to have opened on the day Pho- bos-Grunt launched. This situation was never clearly communicated as it played out in Novem- ber 2011.

But there are broader implications from the Phobos-Grunt mission recovery scenario. A similar countdown clock is set following the first of multiple launches required to build up sufficient mass in LEO for departure to any interplanetary destination. An adequately padded launch cam- paign timeline manages the risk of late departure, but additional exposure to the LEO environ- ment carries its own risks.

(Continued on page 38)

AIAA Houston Section Horizons January / February 2012 Page 37 Page 38

(Continued from page 37) Astrodynamics Reusable infrastructure in LEO, a propellant depot being a notable example, will be particularly challenged to ensure  is sufficiently near zero at a time when an interplanetary destination is properly phased with Earth. This may require deploying such reusable infrastructure at a suffi- ciently high orbit inclination to guarantee all conceivable Earth departure asymptote declinations are accommodated. Sufficiently high inclination will generally incur a performance penalty for all launches supporting the reusable infrastructure's logistics. It may therefore be preferable to adopt single-use, mission-specific architectures for multiple-launch interplanetary mission cam- paigns if they must be staged in LEO.

(Continued on page 39)

Above: The final architecture of the Phobos-Grunt spacecraft and its major components as of 2011. Credit: IKI (Russian Space Re- search Institute).

AIAA Houston Section Horizons January / February 2012 Page 38 Page 39

(Continued from page 38) Astrodynamics

Left: Phobos-Grunt (alternatively Fobos-Grunt) is a Russian mission designed to land on the martian moon Pho- bos and return a sample to Earth. The primary scientific objective is to analyze the sam- ple on Earth to understand the origin and reconstruct the his- tory of Phobos. Specific objec- tives will be to analyze the composition of the material returned and to determine how it related to other material in the solar system, if it contains any particles ejected from the martian surface, protosolar matter, or organic material, if it has been differentiated and to what degree, and the ages of the sample. A robotic arm will collect approximately 100 to 200 grams of samples and de- posit them in a return capsule which will be launched back to Earth. Phobos-Grunt will be launched with a Chinese Mars orbiter aboard, Yinghuo-1. Image and text source for this page: http:// nssdc.gsfc.nasa.gov/planetary/ image/phobos_grunt.jpg. Im- age and text credit for this page: NASA.

Left: This is a full-scale mockup of the Phobos lander, the Mars departure vehicle, and the Earth return capsule. The Russian spacecraft was supposed to collect samples of soil on Mars' moon Phobos and bring the samples back to Earth for detailed study. Cred- it: CNES.

AIAA Houston Section Horizons January / February 2012 Page 39 Page 40

APR Phoenix-E E-Publication SCOTT LOWTHER Man has been travelling into has been considered a viable definitely puts space tourism space for half a century with possibility in the aerospace within the grasp of a far vast- some regularity, but the vast community. er pool of vacationers than the majority of these trips have $20 million price point, it is been at government expense. One thing has kept the con- still beyond the reach of most Many people have wanted to cept from gaining acceptance: people, and as “space tour- Aerospace Projects Review (APR) be space tourists, to go on cost. A few super-rich adven- ism,” it falls rather short of is presented by Scott Lowther, vacation to an orbiting Space turers have indeed gone on the real goal of many... orbit. whose unique electronic publica- Hilton or a cruise around the vacations in space… at the In order to achieve that goal, tion is described as a “journal de- Moon, but until quite recent- cost of $20 million or so for a an orbital vehicle would need voted to the untold tales of aero- ly, the whole idea of space week in cramped space sta- to be developed that would be spacecraft design.” More infor- tourism has been largely tions not designed for luxuries orders of magnitude cheaper mation may be found at the follow- laughed at. As far back as the or comfort. Even now, as sub- to build, operate and maintain ing address: late 1960s the likes of Barron orbital tourist craft are being than normal space launch Scott Lowther Hilton (of the Hilton hotel actually built and test flown, systems. 11305 W 10400 N chain) and Krafft Ehricke prices are ranging from Thatcher, UT 84337 gave serious contemplation to $100,000 to $200,000 for just One such vehicle was de- [email protected] space hotels, but it has only a few minutes of zero-g... signed nearly thirty years ago. www.aerospaceprojectsreview.com been within the last half dec- working out to hundreds of Society Expeditions, founded ade or so that space tourism dollars per second. While this in 1974, was a travel compa- ny that focused on exotic Right: Artwork depicting the cruises to locales such as Ant- Phoenix-E in orbit, in Society arctica, the Northwest Pas- Expeditions colors. Image credit: sage and the Middle East, all Scott Lowther. with an eye for luxury. So it was perhaps not surprising that in April of 1985 they announced that a new venture (under the aegis of the “Space Travel Company”) would be offering jaunts into low Earth orbit. “Project Space Voyage” would have its maiden voyage on October 12, 1992, the 500th anniversary of Columbus’ discovery of the Americas. The space vehicle would be the Phoenix-E (E for Excur- sion): a vertical take-off and landing (VTOL) single-stage- to-orbit rocket vehicle to be designed and built by Pacific American Launch Systems, owned by Gary Hudson. The Phoenix-E would require a crew of five and carry twenty passengers in luxury accom- modations. Maximum accel- eration would be 3 g’s, and each passenger would have a large window. The journey (Continued on page 41)

AIAA Houston Section Horizons January / February 2012 Page 40 Page 41

(Continued from page 40) would have exclusive rights unclear. APR would be a simple trip to or- to two Phoenix-E’s for five bit, starting from Vandenberg years, with the option of pur- The Phoenix-E, a modification E-Publication in California. The craft would chasing ten craft. Develop- of the Phoenix single-stage-to- spend 8 to 12 hours in orbit. It ment of the Phoenix-E was orbit (SSTO) that Hudson had would then re-enter and land expected to cost up to been developing since 1982 near the launch site, using $250,000,000, part of which (the Phoenix-C being the cargo rockets for a powered vertical was to be raised by selling version), was in many ways landing. The ticket price was stock, part by selling seats in similar to but much smaller $52,000. advance. As of January 1986, than the ROMBUS SSTO de- at least 150 people had paid a sign. ROMBUS was designed It was expected that develop- $5,000 deposit. STC expected in 1962 by Phillip Bono of ment of the Phoenix-E would to launch up to 5,000 passen- Douglas Aircraft to orbit nearly take three and a half years, gers by 1997. Whether this a million pounds of payload. followed by fifty test flights number was based on serious As with Phoenix, ROMBUS over a year and a half. The market studies or was just featured a truncated conical Below: Diagram courtesy Space Travel Company (STC) what they hoped to attain is (Continued on page 42) Gary Hudson, via Tom Brosz.

AIAA Houston Section Horizons January / February 2012 Page 41 Page 42

(Continued from page 41) feet per second, would use an sites would be used, the pri- APR propulsion and propellant oxygen-rich mixture ratio of mary structural material was E-Publication module with a toroidal aero- 13:1, with Mode 2 using a to be aluminum. Overall vehi- spike engine, giving automat- hydrogen-rich mix ratio of cle height would be 57 feet ic altitude compensation from 7:1. Mode 1 would reduce while sitting on its four de- sea level to space. Both the specific impulse to 355 se- ployable landing legs. Gross Phoenix and the ROMBUS conds, but the benefit was that liftoff weight would be about would launch vertically and re low-density hydrogen would 454,600 pounds. -enter tail first, with the blunt be traded for high density aerospike engine forming the oxygen, greatly reducing the While STC failed to raise the heat shield. Both would use a mass of tankage and associat- funds needed to bring the small amount of the remain- ed structures. Mode 2 would Phoenix-E to life, the design ing launch propellant for a have a higher specific impulse continued to evolve over the vertical landing, with deploy- (Isp) of 463 seconds. The next decade or so. The board able landing gear allowing Phoenix “Mainstage” had a of directors of the STC in- touchdowns on concrete land- maximum diameter of 384 cluded Maxwell Hunter II, ing pads. Unlike ROMBUS, inches, a structural weight of formerly of McDonnell- Phoenix would use “slush” 25,000 pounds and a propel- Douglas, where he had head- hydrogen and oxygen; by lant load of 400,000 pounds. ed up development of the lowering the propellant tem- The Mainstage was basically Thor intermediate range bal- peratures to their freezing a self-contained vehicle, with listic missile (IRBM), the points, the bulk propellant everything atop it being pay- Delta space launcher and the densities would be increased load, whether that was un- S-IVb stage of the Saturn V. by 14% or more, aiding with manned cargo or a module At the time, Hunter worked at the mass ratio of the vehicle. with a cockpit and twenty Lockheed, and in 1988 devel- Additionally, the rocket en- passengers. The net payload oped the design of the “X- gines would have two operat- Below: Diagram courtesy weight that the Mainstage Rocket,” a conical SSTO. In ing modes. Mode 1, used Gary Hudson, via Tom Brosz. could inject into orbit was 1989 Hunter refined the de- from launch to about 7,500 20,000 pounds. While compo- sign further on his own, creat- ing the SSX (Space Ship Ex- perimental), a design meant for cheap space launch for the Space Defense Initiative. To- gether with the Phoenix de- signs, Hunter’s SSX helped lead the Ballistic Missile De- fense Organization to fund development of the Delta Clipper concept, producing the DC-X test vehicle. Society Expeditions filed for bank- ruptcy in 2004.

More on the Douglas ROM- BUS SSTO can be found in issue V2N6 of Aerospace Projects Review, available at: www.aerospaceprojectsrevie w.com.

AIAA Houston Section Horizons January / February 2012 Page 42 Page 43

EAA and EAA Chapter 12 Information Chapter Mission brings people together with an tion and aviation technology The Experimental Air- interest in recreational avia- is encouraged to participate craft Association's Chapter tion, facilitating social inter- (EAA membership is not re- 12, located at Ellington Field action and information shar- quired, but encouraged). in Houston, is an organization ing between aviation enthusi- Meetings are generally from that promotes all forms of asts. Many of the services that 6:30 PM to 9 PM at Ellington recreational aviation. The EAA offers provide valuable Field in Houston Texas. We In our May 2011 issue we organization includes interest support resources for those welcome everyone. Come as started our series EAA/AIAA in homebuilt, experimental, that wish develop and im- you are and bring a guest; we profiles in general and experi- antique and classic, warbirds, prove various skills related to are an all aviation friendly mental aviation with Lance aerobatic aircraft, ultra lights, aircraft construction and res- organization! Borden, who is rebuilding his helicopters and commercially toration, piloting, aviation Inland Sport airplane, an air- manufactured aircraft and the safety, and aviation education. craft manufactured by his associated technologies. Every individual and organi- grandfather’s 1929 - 1932 zation with an interest in avia- company. The second in this This organization series was a profile of Paul F. Ideas for a meeting? Contact Richard at rtsessions “at” earthlink.net, Chapter web site: Dye. The third profile will www.eaa12.org probably appear in our next Experimental Aircraft Association web site: www.eaa.org issue. This series was suggest- ed by Richard Sessions of EAA Chapter 12. Scheduled/Preliminary Chapter 12 Event/Meeting Ideas and Recurring Events: Monthly Meeting: Chapter 302, 2nd Saturday, 10 AM, Lone Star Builder’s Center, Lone Star Executive, Conroe TX EAA is the Experimental Air- 1st Saturday of each month – La Grange TX BBQ Fly-In, Fayette Regional (3T5) craft Association. The Houston 1st Saturday – Waco/Macgregor TX (KPWG), Far East Side of Field, Chap 59, Pancake Break- Chapter is #12, one of the ear- fast with all the goodies 8-10 AM, Dale Breedlove, jdbvmt “at” netscape.com liest created among the hun- 2nd Saturday – Lufkin TX Fajita Fly-In (LFK) dreds of chapters. 2nd Saturday – New Braunfels TX Pancake Fly-In 3rd Saturday – Wings & Wheels, 1941 Air Terminal Museum, Hobby Airport, Houston TX www.eaa12.org. 3rd Saturday – Jasper TX BBQ Lunch Fly-In (JAS) 3rd Saturday – Tyler TX Breakfast Fly-In, 8-11, Pounds Field (TYR) 4th Saturday – Denton TX Tex-Mex Fly-In 4th Saturday – Leesville LA Lunch Fly-In (L39) 4th Saturday – Shreveport LA Lunch Fly-In (DTN) Last Saturday – Denton Fly-In 11AM-2 PM (KDTO)

Left: RV-9A on the ramp at Wings & Wheels of August 20, 2011, at the 1940 Air Terminal Museum at Hobby Airport in Houston, Texas. From Wikipedia: “The Van's RV-9 and RV -9A are two-seat, single-engine, low- wing homebuilt airplanes sold in kit form by Van's Aircraft. The RV-9 is the tail-wheel equipped version while the RV-9A features a nose-wheel. The RV-9 was built around a newly- designed high aspect ratio wing, fea- turing a Roncz airfoil. It is similar in size and weight to RV-6 and is exter- nally similar to the RV-6 and the RV- 7.” Image credit: 1940 Air Terminal Museum (www.1940airterminal.org).

AIAA Houston Section Horizons January / February 2012 Page 43

Page 44

Current Events

Right: Astronaut Dottie- Metcalf-Lindenberger. Image credit: www.ted.com.

Right: Notes from the pro- TEDx NASA/JSC gram document for this recent Women

TEDx event. One of the event 9:00 AM 11:55 AM December 1, 2011 organizers was Ted Kenny/ Teague Auditorium NASA-JSC, our current AIAA Sherry Hatcher & Courtney Cady Coleman (Why 6

Houston Section history tech- McManus (MC: Welcome) Months in Space is Not x = independently organized nical committee Chair. Re- Enough) TED event porter: Douglas Yazell. Ellen Ochoa (Welcome) Technology, Entertainment, Julie Robertson (Experiments and Design (TED) Jessie Fernandez (First Join- that Can’t be Done on Earth) “Ideas Worth Spreading” ing NASA) www.ted.com Keiko Nakamura-Messenger

Cindy McArthur (NASA Edu- (Exploring the Solar System Reshaping the Future: Re- cation: Building the Next with a Microscope) silience, Relationships, Re- Generation of Explorers birth, and Reimagine Dolores Petropoulos (Re-

Lora Bailey (Engineering Imagining) TED is a small nonprofit de- Innovation) voted to Ideas Worth Spread- 12:45 PM ing. It started in 1984 as a Dottie Metcalf-Lindenberger conference bringing people (STEM Education: The Root Lunch with Leaders together from three worlds: of our Future) Technology, Entertainment, Look for these videos on the Design. Since then its scope 10:00 AM related TEDx web site. Start has become even broader. searching for that at ted.com.

Live Feed from New York This event was open to every- City End one (women and men) who

support and encourage wom-

en in their lives.

AIAA Houston Section Horizons January / February 2012 Page 44 Page 45

Current Events

Above: a cropped image from JSC2012-E-017833. Image credit: NASA.

Above: JSC2012-E-017837 (4 Jan. 2012) --- Multiple images of the International Space Station flying over the Houston area have been combined into one composite image to show the progress of the station as it crossed the face of the moon in the early evening of Jan. 4. The station, with six and cosmonauts currently aboard, was flying in an orbit at 390.8 kilometers (242.8 miles). The space station can be seen in the night sky with the naked eye and a pair of field binoculars may reveal some detail of the struc- tural shape of the spacecraft. Station sightings in the area will be possible again (weather permitting) Friday, Jan. 6, beginning at 6:11 p.m. CST. Viewing should be possible for approximately six minutes as the station moves from 10 degrees above west- northwest to 10 degrees above south-southeast. The maximum elevation will be 44 degrees. To find sighting details by city, visit: http://go.usa.gov/81R. Equipment used by the NASA photographer, operating from NASA's Johnson Space Center, was as follows: Nikon D3S, 600mm lens and 2x converter, Heavy Duty Bogen Tripod with sandbag and a trigger cable to minimize camera shake. The camera settings were as follows: 1/1600 @ f/8, ISO 2500 on High Continuous Burst. Photo credit: NASA.

AIAA Houston Section Horizons January / February 2012 Page 45

Page 46

Staying Informed

Right: ISS030-S-001 (April 2011) --- The International Space Station (ISS) program is completing the transition from assembly to full utilization as hu- mankind celebrates the golden anniversary of human space exploration. In recognition of these milestones and especially of the contribution of those whose dedication and ingenuity make spaceflight possible, a fully assembled ISS is depicted rising above a sunlit Earth limb. Eastward of the sunlit limb, the distinctive portrayal of Earth's surface illuminated by nighttime city lights is a reminder of mankind's presence on the planet, most readily apparent from space only by night, and commemorates how human beings have transcended their early bonds throughout the previous 50 years of space exploration. The ISS, a unique space-based outpost for research in biological, physical, space and Earth sciences, in the words of the crew members, is an impressive testa- ment to the tremendous teamwork of the engineers, scientists and technicians from 15 countries and five national space agencies. The six crew members of Expedition 30, like those who have gone before them, express that they are honored to represent their coun- tries and the ISS team in conducting research aboard the station and adding to the body of knowledge that will enable the world's space faring countries to more safely and more productively live, work and explore outer space, paving the way for future missions beyond low Earth orbit, and inspiring young people to join in this great adventure. Image credit: NASA.

Who is on ISS now? As of February 25, 2012, it is the crew of Expedition 30.

Above: ISS030-S-002 (19 July 2011) --- Expedition 30 crew members take a break from training at NASA's Johnson Space Center to pose for a crew portrait. Pictured on the front row are NASA astronaut Dan Burbank, commander; and Russian cosmonaut Oleg Kononenko, flight engineer. Pictured from the left (back row) are Russian cosmonauts Anton Shkaplerov and Anatoly Ivanishin; along with astronaut Andre Kuipers and NASA astronaut Don Pettit, all flight engineers. Photo credit: NASA and International Space Station partners.

AIAA Houston Section Horizons January / February 2012 Page 46

Page 47

Editor’s note: Daniel Adamo was already sending Figures 1 and 2 to an astrodynamics contact list on December 18, 2011. Sun-grazing comet Lovejoy stunned the world of astronomy by surviv- Staying Informed ing its spectacular encounter with the Sun on December 16, 2011.

Left: Image credit: Daniel R. Adamo, Astrodynamics Con- sultant.

Figure 1. A plot in Earth's Sun-centered orbit plane (the ecliptic) illustrates Comet Lovejoy's grazing flight past the Sun during December 2011. From Earth's perspective, Lovejoy appears to tunnel through the Sun. The comet's orbit period is 314 years, with its maximum solar dis- tance (aphelion) more than 92 times Earth's.

AIAA Houston Section Horizons January / February 2012 Page 47

Page 48

Editor’s note: Daniel Adamo’s figures clarify some aspects of comet Lovejoy’s close pass by the Staying Informed Sun. He called our attention to this web site, Comet Lovejoy Survival: http://sungrazer.nrl.navy.mil/index.php?p=news/birthday_comet where Karl Battams of the Naval Research Laboratory (NRL) communicates the excitement and surprise of the comet watchers as they monitor results of comet Lovejoy’s Sun grazing from several spacecraft observatories.

Right: Image credit: Daniel R. Adamo, Astrodynamics Con- sultant.

Figure 2. This plot in the plane of Comet Lovejoy's orbit illustrates its Sun-centered motion during a two-day interval containing closest approach (perihelion). The Sun's humanly per- ceived surface (photosphere) is shaded where it is not observable from Earth's perspective. Dot- ted projection lines indicate Lovejoy's orbit lies well below the ecliptic plane except for a brief interval from a few minutes before perihelion until a few hours afterward. A collision with Earth is therefore impossible unless this orbit is significantly altered. Comet Lovejoy orbit data are from JPL Solar System Dynamics solution #24.

AIAA Houston Section Horizons January / February 2012 Page 48

Page 49

Editor’s note: On Dec. 16, 2011, Sun-grazing comet Lovejoy surprised astronomers by sur- viving its spectacular pass by the Sun. Its long tail was lost but was expected to grow back, Staying Informed as noted by Karl Battams on the web site noted on the previous page. Comet Lovejoy was already big news and historic because of its survival when, on Dec. 21, 2011, astronaut Dan Burbank took photographs and video like the one shown in the bottom right corner of this page. He was in orbit around the Earth onboard the International Space Station (ISS), and this opportunity was a surprise. The next day, he took photographs like the one below.

Left: ISS030-E-015472 (22 Dec. 2011) --- Comet Lovejoy is visible near Earth's horizon in this nighttime image photographed by NASA astronaut Dan Burbank, Ex- pedition 30 commander, onboard the International Space Station on Dec. 22, 2011. Image credit: NASA.

Below: ISS030-E-014379 (21 Dec. 2011) --- Comet Lovejoy is visible near Earth's horizon in this nighttime image photographed by NASA astro- naut Dan Burbank, Expedition 30 commander, onboard the Interna- tional Space Station on Dec. 21, 2011. Image credit: NASA.

AIAA Houston Section Horizons January / February 2012 Page 49 Page 50

AIAA Houston Section events & other events related to aeronautics & astronautics. This Jan. / Feb. 2012 issue of Horizons is scheduled to be online by Feb. 29, 2012. All items are subject to change without notice.

AIAA Houston Section council meetings: for info, email secretary[at]aiaa-houston.org Time: 5:30 - 6:30 PM usually Day: First Monday of most months except for holidays. Location: NASA/JSC Gilruth Center is often used. The room varies. Monday, March 5, 2012, Monday, April 2, 2012, Monday, May 7, 2012, and Monday, June 4, 2012. The new AIAA year starts July 1, 2012.

Tuesday, March 27, 2012: Dinner meeting. Speaker: Douglas Terrier, NASA/JSC. Location: NASA/JSC Gilruth Center Friday and Saturday, April 6 and 7, 2012: See pages 53 for related deadlines. AIAA Region IV Student Conference, https://region4.aiaastudentconference.org/ Location: NASA/Johnson Space Center Saturday, April 7, 2012 Ninth Annual Yuri’s Night Houston 5k Fun Run/Walk. Challenger Seven Memorial Park, 8:00 AM Kids’ 1k, 8:15 AM 5k Fun Run/Walk. www.yurisnighthouston.net, ynh.funrun[at]gmail.com. Space Day? The Celebration? Please see the web site for details. Yuri’s Night Houston 2012 is an AIAA Houston Section event. Friday, May 18, 2012: ATS 2012. See page 52. AIAA Houston Section Annual Technical Symposium (ATS 2012) June 2012, on a weeknight (Monday - Thursday): Dinner meeting. Speaker: Norman Chaffee, NASA/JSC retired Additional speakers include: Guy Thibodaux, NASA/JSC retired, James C. McLane, Jr., NASA/JSC retired. Location: TBD (possibly the 1940 Air Terminal Museum at Hobby Airport, www.1940airterminal.org) Celebrating the 50th anniversary of AIAA Houston Section.

AIAA National & International Conferences

20 - 21 March 2012: Congressional Visits Day Location: Washington, DC Venue: Capitol Hill, Type: AIAA Conference 26 - 28 March 2012: 10th U.S. Missile Defense Conference and Exhibit, Type: AIAA Conference Location: Washington, DC Venue: Ronald Reagan Building and International Trade Center 23 - 26 April 2012: 53rd AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference 20th AIAA/ASME/AHS Adaptive Structures Conference 14th AIAA Non-Deterministic Approaches Conference 13th AIAA Gossamer Systems Forum 8th AIAA Multidisciplinary Design Optimization Specialist Conference Location: Honolulu, Hawaii Venue: Sheraton Waikiki 9 May 2012: The 2012 Aerospace Spotlight Awards Gala, Washington, DC 22 - 24 May 2012: Global Space Exploration Conference, Washington, DC 7 June 2012: Aerospace Today… and Tomorrow - An Executive Symposium Location: Williamsburg, Virginia

19 - 21 June 2012: Infotech@Aerospace 2012, Garden Grove, California Calendar 25-28 June 2012: AIAA Fluid Dynamics and Co-Located Conferences and Exhibit Location: New Orleans, Louisiana

Horizons: published bimonthly at the end of February, April, June, August, October & December at www.aiaa-houston.org

AIAA Houston Section Horizons January / February 2012 Page 50 Page 51

Cranium Cruncher Challenge DR. STEVEN E. EVERETT

In the last issue, the reader was challenged to compute the volume of a pair of intersecting pipes of radius r and length 4r with only the formulas for the area of a circle and the volume of a sphere, and without using calculus. The volume of this region, called a bicylinder, was known to Archimedes, long before the invention of calculus. It can be derived by first deter- mining the volume of the intersecting space, called a Steinmetz solid, whose edges are shown in black. A representative vertical slice is illustrated by the red square. The ratio of the area of the inscribed circle, also in red, to that of the square is easily shown to be /4. It may also be noted that the set of circles which are inscribed in the slices of the Steinmetz solid are the intersections of a sphere with radius r, having a volume of 4/3  r3. If we note that the ratio of the areas of the circles to that of the squares is equal to the ratio of the sphere to the Steinmetz solid, its volume can then be computed as 16/3 r3. Since each cylinder has length 4r, their individual volumes are 4  r3. Multiplying by two and subtracting the intersecting volume yields a total volume of (8  - 16/3) r3.

This week’s puzzle:

A rather less experienced engineer than that in last week’s puzzle has been put in charge of connecting the wiring in a new spacecraft. He is presented with a pile of 100 electrical ca- bles, each with a male and a female end, and so he decides to begin connecting the ends of them randomly. He repeats the process until there are no loose ends left. What is the expected value of the number of loops he has created?

Send solutions to steven.e.everett at boeing.com

AIAA Houston Section Horizons January / February 2012 Page 51 Page 52

The Early Warning Flyer is partially hidden on this page. It is presented in full on page three of Section News our last issue, the November / December 2011 Horizons newsletter: www.aiaa-houston.org.

One keynote speaker is con- firmed so far: Mark Geyer, NASA/JSC (Orion MPCV).

www.aiaa-houston.org

AIAA Houston Section Horizons January / February 2012 Page 52 Page 53

The American Institute of Section News Aeronautics and Astronautics

AIAA Region IV Student Conference Friday and Saturday, April 6 - 7, 2012 NASA/Johnson Space Center, Houston, Texas Hosted by AIAA Houston Section and UT Austin https://region4.aiaastudentconference.org/

Date Event Saturday, January 14, 2012, 12:00am Registration Opens Monday, March 12, 2012, 11:59pm Registration Closes Monday, March 12, 2012, 11:59pm Abstracts Due Wednesday, March 14, 2012, 11:59pm Papers Due Monday, March 19, 2012, 11:59pm Cancellation Deadline Thursday, April 5, 2012, 11:59pm Presentations Due Friday, April 6 - Saturday, April 7, 2012 Conference

AIAA Houston Section Horizons January / February 2012 Page 53

Page 54

Titles of AIAA Conference Papers Authored by AIAA Houston Section Members COMPILED BY THE EDITOR USING THE AIAA E-LIBRARY, EMAIL EDITOR-IN-CHIEF[AT]AIAA-HOUSTON.ORG 50th AIAA Aerospace Sciences Meeting including the New Horizons Forum and Aerospace Exposition Nashville, Tennessee January 9-12, 2012

Vortex Lift Waverider Configurations Patrick Rodi Lockheed Martin Corporation, Houston, TX, AIAA-2012-1238

Assessing Uncertainties in Boundary Layer Transition Predictions for HIFiRE-1 at Non-zero Angles of Attack Lindsay Marek NASA Johnson Space Center, Houston, TX, AIAA-2012-1015

An Investigation of the Relationship Between the Residual Strength of Glass and Pit Diameter After Hypervelocity Impact Nehemiah Williams University of Tennessee Space Institute, Tullahoma, TN; James McMahon NASA Johnson Space Center, Hou- ston, TX, AIAA-2012-873

Continuing Validation of Computational Fluid Dynamics for Supersonic Retropropulsion Daniel Schauerhamer Jacobs, Houston, TX; Kerry Trumble NASA Ames Research Center, Moffett Field, CA; William Kleb NASA Langley Research Center, Hampton, VA; Jan-Renee Carlson NASA Langley Research Center, Hampton, VA; Karl Edquist NASA Langley Research Center, Hampton, VA, AIAA-2012-864

Experimental Measurements of Heat Transfer Rates Through a Lunar Regolith Simulant in a Vibro-Fluidized Reactor Oven Vedha Nayagam NASA Glenn Research Center, Cleveland, OH; Kurt Sacksteder NASA Glenn Research Center, Cleveland, OH; Aaron Paz NASA Johnson Space Center, Houston, TX, AIAA-2012-635

The lagRST Model: a Turbulence Model for Non-Equilibrium Flows Randolph Lillard NASA Johnson Space Center, Houston, TX; Michael Olsen NASA Ames Research Center, Moffett Field, CA; Bran- don Oliver NASA Johnson Space Center, Houston, TX; Gregory Blaisdell Purdue University, West Lafayette, IN; Anastasios Lyr- intzis Purdue University, West Lafayette, IN, AIAA-2012-444 (Continued on page 55)

AIAA Houston Section Horizons January / February 2012 Page 54

Page 55

(Continued from page 54)

Lock-in of Elastically Mounted Airfoils at High Angles of Attack Robert Ehrmann Texas A&M University, College Station, TX; Kristina Loftin Texas A&M University, College Station, TX; Shalom Johnson Texas A&M University, College Station, TX; Edward White Texas A&M University, College Station, TX, AIAA-2012-1209

Boundary-Layer Transition on a Flared Cone in the Texas A&M Mach 6 Quiet Tunnel Jerrod Hofferth Texas A&M University, College Station, TX; William Saric Texas A&M University, College Station, TX, AIAA-2012 -923

JoKHeR: NPSE Simulations of Hypersonic Crossflow Instability Joseph Kuehl Texas A&M University, College Station, TX; Eduardo Perez Texas A&M University, College Station, TX; Helen Reed Texas A&M University, College Station, TX, AIAA-2012-921

A Novel Design of an Exo-Solar Planet Imager Hyerim Kim Texas A&M University, College Station, TX; Dastan Khussainov Texas A&M University, College Station, TX; Michael Kim Texas A&M University, College Station, TX; James Quinn Texas A&M University, College Station, TX; David Hyland Texas A&M University, College Station, TX, AIAA-2012-879

Repetitively Pulsed Hypersonic Flow Apparatus for Advanced Laser Diagnostic Development Rodrigo Sanchez-Gonzalez Texas A&M University, College Station, TX; Ravichandra Srinivasan Texas A&M University, College Station, TX; Jerrod Hofferth Texas A&M University, College Station, TX; Doyong Kim Texas A&M University, College Station, TX; Rodney Bowersox Texas A&M University, College Station, TX; Simon North Texas A&M University, College Station, TX, AIAA- 2012-733

Freestream Turbulence Measurements in a Continuously Variable Hypersonic Wind Tunnel Michael Semper Texas A&M University, College Station, TX; Brandon Pruski Texas A&M University, College Station, TX; Rodney Bowersox Texas A&M University, College Station, TX, AIAA-2012-732

Feasibility of One-Dimensional Rotational and Vibrational Raman in High Speed Flames Alex Bayeh Texas A&M University, College Station, TX; Adonios Karpetis Texas A&M University, College Station, TX, AIAA-2012- 613

AggieSat2 Student Satellite Mission John Graves Texas A&M University, College Station, TX; Joseph Perez Texas A&M University, College Station, TX; Helen Reed Texas A&M University, College Station, TX, AIAA-2012-434

Proper Orthogonal Decomposition Applied to the Reynolds-Averaged Navier--Stokes Equations Brian Freno Texas A&M University, College Station, TX; Thomas Bren- ner Texas A&M University, College Station, TX; Paul Cizmas Texas A&M University, College Station, TX, AIAA-2012-314

Modeling and Analysis of Eagle Flight Mechanics from Experimental Flight Data Steven Shepherd Texas A&M University, College Station, TX; John Vala- sek Texas A&M University, College Station, TX, AIAA-2012-27

AIAA Houston Section Horizons January / February 2012 Page 55 Non-Profit Organization U.S. POSTAGE PAID AIAA Houston Section PERMIT NO. 1 P.O. Box 57524 Webster , Texas Webster, TX 77598

ISS031-S-001 (September 2011) --- Thin crescents along the horizons of Earth and its moon depict Interna- tional Space Station (ISS) Expedition 31. The shape of the patch represents a view of our galaxy. The black back- ground symbolizes the research into dark matter, one of the scientific ob- jectives of Expedition 31. At the heart of the patch are Earth, its moon, Mars, and asteroids, the focus of cur- rent and future exploration. The ISS is shown in an orbit around Earth, with a collection of stars for the Ex- Above: ISS031-S-002 (14 July 2011) --- Expedition 31 crew members take a break from pedition 30 and 31 crews. The small training at NASA's Johnson Space Center to pose for a crew portrait. Pictured on the front row are Russian cosmonauts Oleg Kononenko (right), commander; and Gennady Padalka, stars symbolize the visiting vehicles flight engineer. Pictured from the left (back row) are NASA astronaut Joe Acaba, Russian that will dock with the complex dur- cosmonaut Sergei Revin, European Space Agency astronaut Andre Kuipers and NASA as- ing this expedition. Photo credit: tronaut Don Pettit, all flight engineers. Photo credit: NASA. NASA and its International Partners.

AIAA Mission & Vision Statement The shaping, dynamic force in aerospace - THE forum for innovation, excellence and global leadership. AIAA advances the state of aerospace science, engineering, and technological leadership. Core missions include communications and advocacy, products and programs, membership value, and market and workforce development. The World's Forum for Aerospace Leadership

Become a member of AIAA Are you interested in becoming a member of AIAA, or renewing your membership? You can fill out your membership application online at the AIAA national web site: www.aiaa.org. Select the AIAA membership option.

AIAA Houston Section Horizons January / February 2012 Page 56