The PLANETARYPLANETARY REPORT REPORT

Volume XXII Number 1 January/February 2002

Mercury Revisited Volume XXII Table of Number 1 Contents January/February 2002 A PUBLICATION OF Features From Opinion: Whither, O Splendid Ship? The 4 This issue’s opinion essay takes its title from a Robert Bridges poem evoking Editor the bold, adventurous spirit that drove mariners in an earlier age of exploration. Here, two modern explorers lay out the course they urge us to set among the planets; they are Jim Burke, who led the United States’ first attempt to reach the e welcome some pretty amazing Moon, and John Young, the first man to have flown six times in space: in the people through the doors of W Gemini, Apollo, and space shuttle programs. Their experience is unparalleled and The Planetary Society. Recently, we’ve their advice not to be ignored. been seeing a bit of Pascal Lee, a former student of our cofounder Carl Sagan. The Little Planet With the Big Iron Heart For the past five years, Lee has been 6 Only one spacecraft has ever visited Mercury, the planet closest to the Sun. organizing the fascinating field research But improved technology and increased scientific attention are fueling new interest project on Devon Island in the Canadian in this little world. Distinguished science writer Robert Burnham explores this High Arctic. revived interest in Mercury and details plans to send spacecraft to study the planet. The overall effort is called the NASA Haughton-Mars Project (HMP), after From the Earth to Mars Haughton Crater, which serves as the 12 Part One: A Crater, Ice, and Life focus for the scientific research. The Devon Island in the Canadian High Arctic is the world’s largest uninhabited island Mars Society has built its Flashline Mars for most of the year. But now, every summer, a crowd of scientists and aspiring Analog Research Station on Devon explorers descend on Devon to study the island as an Earthly analog for Mars. Island and cooperates with Pascal’s Pascal Lee, who leads the annual expeditions to this remote corner of Earth, begins research program. here a two-part feature on the work that may one day lead humans to Mars. Last summer, Society Executive Director Lou Friedman visited Devon The 2002 Shoemaker NEO Grants: Island to further develop a new initiative 19 It’s Time to Propose! called Mars Outposts. Under the leader- The Planetary Society awards substantial grants to advance the discovery and ship of Bruce Betts, our new director of characterization of comets and asteroids passing close by Earth. Do you have an projects, we are investigating technology observation program that might qualify? If so, it’s time to get that proposal in! for Mars exploration that might include remote-controlled airplanes, smart rovers, instrumented balloons, or other Departments novel means to study difficult terrains. All this leads, of course, to what we 3 Members’ Dialogue hope will be a human presence on Mars. Since 1985, human missions to Mars 18 World Watch have been an avowed goal of The Plane- 20 Questions and Answers tary Society. With the help of friends like Pascal, as well as our members, we are 22 Society News making progress toward that goal. —Charlene M. Anderson Contact Us On the Cover: Mailing Address: The Planetary Society, 65 North Catalina Avenue, Pasadena, CA 91106-2301 This mosaic of Mercury is compiled from images taken by General Calls: 626-793-5100 Sales Calls Only: 626-793-1675 Mariner 10 as it approached the planet on March 29, 1974. E-mail: [email protected] World Wide Web: http://planetary.org Mercury's ancient cratered surface can tell us much about the formation of the inner solar system. In the next decade, two new The Planetary Report (ISSN 0736-3680) is published bimonthly at the editorial offices of The Planetary Society, 65 North Catalina Avenue, Pasadena, CA 91106- 2301, 626-793-5100. It is available to members of The Planetary Society. Annual dues in the US are $30 (US dollars); in Canada, $40 (Canadian dollars). spacecraft will visit Mercury, the least-explored terrestrial planet, Dues in other countries are $45 (US dollars). Printed in USA. Third-class postage at Pasadena, California, and at an additional mailing office. Canada Post Agreement Number 87424. to continue the exploration Mariner 10 began almost 30 years ago. Editor, CHARLENE M. ANDERSON Copy Editor, AMY SPITALNICK Associate Editor, DONNA ESCANDON STEVENS Proofreader, LOIS SMITH Image: JPL/NASA. Reprocessed by Mark S. Robinson, Northwestern University. Managing Editor, JENNIFER VAUGHN Art Director, BARBARA S. SMITH Technical Editor, JAMES D. BURKE Viewpoints expressed in columns or editorials are those of the authors and do not necessarily represent positions of The Planetary Society, its officers, or advisers. ©2002 by The Planetary Society. Cofounder CARL SAGAN 1934–1996

Board of Directors Chairman of the Board BRUCE MURRAY Members’ Professor of Planetary Science and Geology, California Institute of Technology President Dialogue WESLEY T. HUNTRESS JR. Director, Geophysical Laboratory, Carnegie Institution of Washington Vice President NEIL DEGRASSE TYSON Astrophysicist and Director, Hayden Planetarium, American Museum of Natural History Executive Director LOUIS D. FRIEDMAN A Science Mystery ANN DRUYAN We welcome the nuclear power theological would be generated author and producer The “Strange Acceleration of initiative, recognizing the need by evidence of the existence of DONALD J. KUTYNA former Commander, US Space Command Pioneer 10 and 11” in the for it in future exploration. We intelligent extraterrestrial life. JOHN M. LOGSDON Director, Space Policy Institute, November/December 2001 is- also recognize the need for nu- Consider the excitement sparked George Washington University sue of The Planetary Report clear power use to be envi- by the possible evidence of an- Advisory Council Chair CHRISTOPHER P. McKAY was one of the best articles of ronmentally safe and ethical. cient microbial life on Mars. planetary scientist, NASA Ames Research Center BILL NYE its kind I’ve read in a while. It Our position, which we will How much more public interest science educator JOSEPH RYAN explained complex technical be developing as the proposal would be generated by picking Executive Vice President and concepts to nonspecialists while moves forward, will consider up a radio signal from another General Counsel, Marriott International ROALD Z. SAGDEEV conveying a very real sense of both needs. planet? Even if unsuccessful in former Director, Institute for Space Research, Russian Academy of Sciences the mystery of space. Congrat- —Louis D. Friedman, finding life, SETI could yield STEVEN SPIELBERG ulations to the authors! Executive Director other scientific discoveries. director and producer KATHRYN D. SULLIVAN President and CEO, Ohio’s Center —NEIL L. INGLIS, Kulpa extends my SETI/car of Science and Industry and former astronaut Bethesda, Maryland I think the decisions by Presi- radio analogy by saying that “if MARIA T. ZUBER dent George W. Bush and [NASA our listening to the radio, while Professor, Massachusetts Institute of Technology Nuclear Propulsion Administrator] Sean O’Keefe having no impact on our driving Advisory Council JIHEI AKITA I was somewhat alarmed that to cancel the Outer Planets ability, would cost so much as Executive Director, The Planetary Society, Japan BUZZ ALDRIN the latest NASA budget focus- program (including the Pluto– to deplete our gas budget for the Apollo 11 astronaut es on the development of nu- Kuiper Belt mission) and re- drive, then certainly we should RICHARD BERENDZEN educator and astrophysicist clear propulsion systems, and place it with New Frontiers stop listening to that radio.” JACQUES BLAMONT Chief Scientist, even more surprised that The (nuclear energy development) I must respond, only half- Centre National d'Etudes Spatiales, France RAY BRADBURY Planetary Society seemingly is a prudent choice. Pluto can jokingly and with a nod to Carl poet and author supports these plans. While I wait. So can Europa. Sagan’s Contact: but what if, DAVID BRIN generally appreciate all efforts —RUSSELL B. CLOUSING, while listening to the radio, we author FRANKLIN CHANG-DIAZ to develop new technology for Lansing, Michigan learn where to get cheaper gas NASA, Astronaut Office ARTHUR C. CLARKE more efficient planetary explo- or, better yet, how to make our author On Clearing the Air FRANK DRAKE ration, I’m worried about the car more fuel efficient? President, SETI Institute; Professor of Astronomy and Astrophysics, possible risks involved with In the November/December —SCOTT PEARSON, University of California, Santa Cruz nuclear systems, especially Members’ Dialogue, Zenon St. Paul, Minnesota STEPHEN JAY GOULD Alexander Agassiz Professor of Zoology, since these systems need to be Kulpa repeats his prerequisite Harvard University GARRY E. HUNT transported into orbit. Once in that Planetary Society programs Erratum space scientist, United Kingdom SERGEI KAPITSA space, they would probably not impact our ability to live in space The caption for David Hardy’s Institute for Physical Problems, cause any damage, yet the to be worthwhile. However, the painting, Millennium Planet, Russian Academy of Sciences CHARLES E. KOHLHASE JR. thought that some nuclear reac- Society’s website states that it which appeared on the back mission designer, author, digital artist JON LOMBERG tor could land (or crash) on “supports and advocates explo- cover of the November/Decem- artist Mars or Europa, for example, ration of the solar system and ber issue, did not mention that HANS MARK University of Texas at Austin leaves me uncomfortable. the search for extraterrestrial the painting is from Hardy’s YASUNORI MATOGAWA Maybe you could clarify life” and that it was founded on new book, Hardyware: The Art Institute of Space and Astronautical Science, Japan JOHN MINOGUE what these new technologies those principles. of David A. Hardy, published President, DePaul University PHILIP MORRISON might look like, what risks are Unless someone breaks the by Paper Tiger. (Read a review Institute Professor, involved, and how they could light-speed barrier, space explo- of the book on the Society’s Massachusetts Institute of Technology LYNDA OBST possibly be managed. ration, even within the solar sys- website, planetary.org.) producer ADRIANA OCAMPO In any case, I’d prefer that tem, will continue to rely heavily planetary scientist, Jet Propulsion Laboratory NASA and The Planetary Soci- on remote and earthbound Please send your letters to RISTO PELLINEN Director and Professor, ety focus on less harmful new hardware, not on astronauts. Members’ Dialogue Finnish Meteorological Institute The Planetary Society ROBERT PICARDO technologies such as ion propul- As for SETI, a discovery 65 North Catalina Avenue actor KIM STANLEY ROBINSON sion and solar sailing. would have tremendous rami- Pasadena, CA 91106-2301 author —JOERG BENSCHEIDT, fications. A host of questions or e-mail: DONNA L. SHIRLEY Aachen, Germany scientific, philosophical, and [email protected] Assistant Dean of Engineering, University of Oklahoma 3

THE PLANETARY REPORT JANUARY/FEBRUARY 2002 :

N Whither, O

I O Splendid Ship? N I P of a new phase in history?

O Here, two of us, seasoned in the trials and joys of, respectively, robotic and human probing into the cosmos, present our own ideas. We’ve seen it all from the very beginning. Still, our appetite for new adventures is lively. We do not claim any special predictive skills. But we do believe firmly in the rightness of our cause. We assert that the future is what human energy can make it. We aim to show how that energy might fuel civilization to break through to a new state of functioning: a society with two established homes and a thriving plan- etary outreach, a society immune to Earthly devastation and open to unprecedented evolution. The Opportunity With Skylab, Mir, and now the International Space Station, the world community of in-space builders is laying foun- dations for a structure whose final architecture is yet to be known. Meanwhile, robotic missions are relaying new knowledge whose ultimate uses also remain unknown. Yes, human beings seem able to function for long Is it humankind's destiny to be a multiworld species? We have already left periods in microgravity. Yes, near-Earth space, the Moon, our footprints in lunar soil. Focusing our steps next on an international pro- the asteroids, and Mars are rich in resources of energy gram of policy change, public involvement, and technological development will place the people of Earth on the path to a sustainable future in space. and building materials. And yes, some few—as yet only Illustration: David Hardy a few—applications of space technology do make money. But a vast field of ignorance, and hence of opportunity, remains. Chipping away at that ignorance is the task of a by James D. Burke and John Young vigorous and diverse array of space projects worldwide. As people in more and more nations take up the chal- lenge, not only are space sciences and technologies here are we going next in space? After a brief, advancing, but the idea is spreading that spaceflight is glorious lunar foray driven by national pride essential. As the world is organized today, there is some W yet also expressing humankind’s greatest aspi- duplication and waste. But there are benefits, too, includ- rations, people in industrial nations retreated to a more ing survival of the best concepts and management tools limited vision for human spaceflight. They seemed con- and, most important, wide public acceptance. tent to occupy a thin shell of space around Earth. Increasingly binding international agreements are sus- Meanwhile, the rest of the world continued on with taining long-term commitments to programs both on grand achievements, accompanied by injustice, pestilence, Earth and in space. More than any technical advance or pollution, and war, and with misery sometimes relieved bold individual or national advocacy, this slow and halt- and sometimes aggravated by modern technology. ing shift in public perspective points toward a time when But now, the human race has passed a threshold: barring humans will again travel to the Moon—this time to stay. a failure of resolve and commitment, there will always be Once that happens, not only will humankind be build- human beings living, first, in nearby space stations and, ing a safe haven against natural or self-inflicted terrestrial then, elsewhere. What does this mean for humankind as catastrophe, but also civilization may develop in unparal- a whole? Is this just another flashy stunt, or is it the start leled, even unintended, ways. Whether that will be good or bad in some historic sense is now unknown, but we Views expressed in this article are those of the authors and had better not remain ignorant for long. 4 do not necessarily represent those of The Planetary Society. We have real wars—the war on terrorism, the war on

THE PLANETARY REPORT JANUARY/FEBRUARY 2002 crime, the war on hunger—but the war we must win, public opinion permits. At the same time, we advocate which hardly anyone realizes we are in, is the war on working to influence public opinion by showing, through ignorance. In the exploration of space and Earth, we modest early successes, what is possible. have discovered, just last summer, good evidence that • Let’s enhance education and encourage space advo- the four major extinctions of life-forms on Earth since cacy among people of all ages, so as to call forth a Permian times (about 250 million years ago) were worldwide community of leaders who can sustain multi- caused by impacts. decade spaceflight commitments. This tells us that sooner or later, single-planet species • Let’s build, both on the ground and in low Earth orbit, don’t make it. But when we develop the technologies practical knowledge of human survival in space. needed to live and work successfully on the Moon, Mars, • Let’s determine the accessibility and value of lunar and the asteroids, we will also have technologies enab- resources, including those in the Moon’s polar environ- ling us to better survive on Earth. It would be ironic to ments. have to terraform Earth to survive, but it might be neces- • Let’s drive technology in directions that support long- sary if we cannot avoid a large asteroid or comet impact. term inhabitation outside Earth, including access to and Many years ago, H. G. Wells said it best: “The future is from the Moon and Mars, cultivation of plant and animal a race between education and catastrophe.” What we have life off-Earth, approaches for dealing with hazards, assur- learned tells us Wells was right. We have no idea when ance of human contentment and productivity, and devel- large impacts or supervolcanoes will devastate Earth. But opment of information systems supporting these goals. they are inevitable. So, we’d better continue educating • Let’s implant on the Moon an archive of human know- ourselves, because we may not have a lot of time. ledge and wisdom, both for its intrinsic worth and as an A splendid opportunity is before us: we can reinvig- aid for recovery in the event of a catastrophe on Earth. orate serious discussion of a two-world future, while at • Let’s extend the robotic exploration of Mars from the same time defining and advocating the technical and planetary science research toward applications for human political measures that can make that future happen. exploration. Now, we hope to contribute to this enterprise. • Let’s develop a real understanding of the resource potential of near-Earth asteroids and of the hazard from The Needs asteroid and comet impacts on Earth. From where we stand today, what would it take to bring • Let’s find clean, sustainable energy resources for us into the happy state that we here imagine? People Earth, including, possibly, solar power from space. tend to think first of money, and indeed a lot of money • Let’s experiment with space commerce, allowing will have to flow. However, budgets, whether national markets to determine what is realistic at each stage in or nongovernmental, are not a cause; they are a result. humankind’s penetration of the cosmos. Human decisions lead to allocation of resources, and • Let’s apply our new findings to ameliorating the human judgments set priorities. Thus, the central need condition of people on Earth. Without that, the whole is in the realm of policy. enterprise will be doomed. As market-driven democracy has spread around the world, a pattern of public decision making is emerging. The Payoff Evidence of investment in longer-term futures is abun- What we propose above is not an idle wish list. Many dant. Look, for example, at the dawning worldwide items on the list are already in development, and all have commitment to remedying the human impact on Earth’s been thought about and discussed among serious space environment. advocates. As this kind of forward-looking view takes hold The opinion we wish to leave with readers is this: with among people who have some voice in their government, the coming of spaceflight, we humans have launched it is logical to promote a long-term perspective toward ourselves into yet another unknown future. But in this spaceflight. An international program would aim to meet future, we are unconfined. these needs: first, to develop a policy base and public advocacy structure; second, to maintain an active tech- James D. Burke, technical editor of The Planetary Report, nology program; third, to launch robotic precursor flight recently retired from the Jet Propulsion Laboratory, where missions; and fourth, to continue to develop the skills he had worked since 1949. In 1960–62, he managed the humans require for living off-Earth. first American attempts to place scientific instruments on the Moon. Since then, he has participated in many other The Actions robotic space projects. He is a member of the faculty of the We believe that certain steps are feasible and necessary, International Space University, where he seeks to encour- toward a time when people will be living productively age new space leaders to continue exploring the cosmos. on the Moon, exploiting extraterrestrial resources, and John Young is associate director (technical) at NASA's exploring Mars. Johnson Space Center in Houston. He has been an active We envision a progressive program, starting with today’s astronaut for almost 40 years, flying on the Gemini 3 and policy framework and evolving at whatever rate world 10, Apollo 10 and 16, and STS-1 and STS-9 missions. 5

THE PLANETARY REPORT JANUARY/FEBRUARY 2002 Long ignored, the planet nearest the Sun is back on mission designers’ agendas. Planetary scientists are looking to Mercury for help in understanding Earth and the other rocky planets.

6

THE PLANETARY REPORT JANUARY/FEBRUARY 2002 by Robert Burnham

Left: Mariner 10 closely studied the Caloris Basin, he planet Mercury is famous for being hard to find in visible at left in this image the sky. It’s also hard to find in the annals of solar mosaic, on its first pass Tsystem exploration. Only one spacecraft has ever gone by Mercury in 1974. More there, and that was more than 25 years ago. Meanwhile, a than 1,300 kilometers (800 miles) in diameter, Caloris dozen probes have flown to Mars alone. is not only Mercury’s Yet, Mercury has recaptured the attention of planetary sci- biggest impact structure entists, and both the United States and Europe are building but also one of the largest basins in the entire solar missions to take another look. Why now? One answer is system. Caloris, the Latin better technology. More significantly, however, the trickle of word for heat, got its name Mercury research over the years has reached critical mass, because it sits near the and scientists feel that revisiting this baked little cinder is subsolar point (the spot closest to the Sun) when vital. Mercury anchors one end of the planetary spectrum, Mercury is at perihelion. and understanding it has become essential for knowing how Image: JPL/NASA all terrestrial planets work, including Earth. An Elusive Planet Mercury has never been an easy target. Its orbit deep in the Sun’s gravity well puts many constraints on mission designers, from supplying sufficient fuel to providing adequate heat shielding. Even for Earth-bound study, Mercury is tough. It Right: Improbable as it may always lies less than 28 degrees from the Sun, or about three sound, Mercury might have fist-widths at arm’s length. This means telescopes must view water-ice trapped inside the craters near its poles. Scien- Mercury either through thick air near the horizon or during tists speculate that water full daylight. (Unfortunately, the Hubble Space Telescope delivered by comet or asteroid can’t point near enough to the Sun to catch Mercury.) In a impacts might be a permanent telescope eyepiece, Mercury resembles a tiny, featureless fixture in these forever-shaded holes. This radar image of Moon trembling in turbid air. craters at the planet’s north Such conditions long prevented scientists from knowing pole was captured in July 1999 even the length of Mercury’s day. They once thought the with the Arecibo telescope. Sun’s gravity had forced Mercury’s rotation to match the The craters’ bright floors have the radar signature of ice, but planet’s year, which is about 88 Earth days long. One side doubts remain because some would eternally face the Sun and roast, while the other of the apparent ice deposits looked away and froze. seem to be in craters too small But in 1965, radar signals bouncing off the planet showed and too far from the pole to be cold enough. that Mercury rotates about once every 59 days. This means Mercury’s day lasts two-thirds of its year and that it spins Below: Although Mariner 10 three times for every two trips around the Sun—which pro- revealed only one hemisphere duces a very peculiar day. For example, depending on the of Mercury to us, Earth-based radar images suggested that location, you might see either a double sunrise or sunset, or there might be at least one you could watch the Sun slide backward in the sky at noon. large volcano on the unex- In 1991, radar gave planetary scientists another shock: plored side. However, this recent observation from the strong radar echoes came from small areas near the poles. upgraded Arecibo telescope After working through possible explanations, scientists in Puerto Rico exposes the settled on the least unlikely: subsurface ice. The source is suspected volcano as a bright- probably comets or water-rich asteroids. Their impact would rayed impact crater. Such observations suggest that briefly generate a thin atmosphere of water vapor. Some much of the unexplored side looks similar to the side Mariner saw—but we need Left: The bulk of our limited knowledge of Mercury was gathered dur- more data to be sure. ing Mariner 10’s three passes by the innermost planet in 1974 and 1975. By recalibrating the old data, scientists have gained new insight Radar images: John Harmon, Arecibo Observatory into the planet’s evolution and geological history. This reprocessed view of Mercury’s south pole (rotated here so that south is at the top) was created from data captured on September 21, 1974. The pole is located on the left edge of the large dark crater whose far rim is illuminated at the center of the planet’s limb. Image: JPL/NASA. Reprocessed by Mark S. Robinson, Northwestern University. 7

THE PLANETARY REPORT JANUARY/FEBRUARY 2002 Scientists have debated the existence of volcanic features on Mercury’s surface since Mariner 10 first reached the planet. Comparisons with the Moon’s dark lava mare have led many researchers to conclude that Mercury’s smooth and intercrater plains were formed by volcanism. Others think that they might be more like the light lunar plains formed by crater ejecta. The above images, located east of the Caloris Basin’s rim, resemble both the lava flow fronts of the Imbrium Basin and ejecta flow lobes of the Oriental Impact Basin on the Moon. The white arrows in the first and second frames show the margins of smooth plains. In the third frame, the arrows point to scarps of possible impact or tectonic origin. Images: JPL/NASA, courtesy of James W. Head, Brown University

would migrate to the polar Instead, it has bright, rolling intercrater plains that ap- regions and be trapped by the pear to be the planet’s oldest surface, some 4 billion cold ground in craters whose years old. They may be volcanic flows or impact debris. floors never see sunlight. Inside the Caloris Basin and elsewhere, geologists Water-ice could last billions mapped smooth plains, cratered more lightly and there- of years, buried by the dust of fore younger (about 3.9 billion years). These, too, may later impacts. be volcanic, but Mariner’s images weren’t sharp enough to reveal telltale features, such as domes or lava flow- Mariner’s fronts. Such features might emerge, however, in sharper Reconnaissance views taken by future missions (see page 9). What we know today of Mer- Cutting across craters and plains alike are ridged cury comes largely from scarps a kilometer or two high. They appear to be thrust NASA’s Mariner 10 space- faults marking where the crust has been squeezed and craft, which made three flyby broken. Scientists calculate that if Mercury’s diameter passes in 1974–75. By cur- shrank by only a couple of kilometers, perhaps as its rent standards, Mariner 10 core cooled, this would compress the surface and pro- carried a few crude instru- duce the fault scarps. ments. Moreover, its trajecto- Most surface materials appear rich in anorthosite, a ry allowed it to photograph lightweight, light-color feldspar rock deficient in iron. only 45 percent of Mercury. A recent analysis of old Mariner images shows consid- Still, it was a great advance erable mineralogical variations from place to place. over Earth-based views. Yet, whether these betray lava flows of differing compo- Mariner found Mercury sitions or variegated rock units excavated by impacts— looking superficially lunar. or both—is unclear. The planet has craters and Mercury’s surface is regolith, a layer of debris deeply impact features that range fractured by repeated impacts. If you could scuff it up, from the Caloris Basin, 1,300 you’d find fine powder, bits of impact-produced glass, Prominent fault scarps, often called kilometers (810 miles) across, tiny rock chips, and stones ranging from pebbles to boul- rupes, snake across Mercury’s cratered surface. Scientists think down to the camera’s best ders. During the Mercurian day, the regolith reaches a that the rupes might have formed resolution limit, about 100 maximum temperature of about 740 kelvins (467 degrees as the young planet cooled and meters. The craters show fa- Celsius, or 873 degrees Fahrenheit); it cools at night to condensed, causing its crust to miliar features: central peaks, perhaps 100 kelvins (– 173 degrees Celsius, or – 279 pleat in some places. This feature, called Discovery Rupes, is more ejecta blankets—even rays. degrees Fahrenheit). This day-night temperature range, than 500 kilometers (310 miles) But the craters are shallower the greatest known in the solar system, results from long and up to 1.5 kilometers than lunar ones, and sec- strong sunlight falling on a virtually airless surface. (1 mile) high. ondary impacts from debris Mercury does have a tenuous atmosphere, but its pres- Image: JPL/NASA. Reprocessed by Mark S. Robinson, Northwestern University. lie closer to their primary sure is less than a trillionth that of Earth’s. Mariner found craters. Both effects follow that the atmosphere contains hydrogen and helium (and from Mercury’s stronger possibly oxygen). Ground-based studies added calcium, gravity, 2.5 times the Moon’s. sodium, and potassium, with the last two being the most Mercury also lacks the dominant elements. Surface rocks provide the main source. 8 Moon’s dark lava “seas.” One of Mariner’s surprises was a huge iron core. Occu-

THE PLANETARY REPORT JANUARY/FEBRUARY 2002 See Mercury in 2002 Mercury is at best visibility this year around the times listed below. Look for a brightish “star” low in the west (evenings) or in the east (mornings). A good time of day to look is about 45 minutes after sunset (evenings) or before sunrise (mornings). Binoculars help. Best viewing opportunities are in boldface. Northern Hemisphere evenings: first three weeks of January, late April to early May, late August, mid-October, last half of December Northern Hemisphere mornings: mid-February, mid-June to early July, October

Southern Hemisphere evenings: first three weeks of January, late April to mid-May, August to mid-September, December to early January 2003 Southern Hemisphere mornings: mid-February to late March, early June to early July, early October

pying three-fourths of Mercury’s radius (Earth’s reaches bys. In fact, the first Mer- Mercury Discovery only halfway to the surface), the planet’s core makes up cury pass will image the Guide some 70 percent of its mass. (Earth’s core contributes on- unknown hemisphere, a ly 32 percent of its mass.) Its large core gives Mercury a key prelude to the mis- ONLINE: density (corrected for pressure) of 5.3 times that of water, sion’s orbital phase. BepiColombo’s Mission Page greater than that of any moon or planet, including Earth. The instrument pack- www.sci.esa.int/home/bepicolombo/index.cfm The core is probably the source of the magnetic field age focuses on sampling Goddard Space Flight Center’s Mercury Page surrounding Mercury, Mariner’s other big surprise. Its charged particles, prob- nssdc.gsfc.nasa.gov/planetary/planets/ shape is a dipole, like Earth’s field, though it has only ing the magnetic field, mercurypage.html 1 percent the strength. An important task for new mis- studying the scanty at- JPL’s Mercury Page sions is to map the field thoroughly and determine what mosphere, mapping the pds.jpl.nasa.gov/planets/welcome/ is generating it. surface geology and mercury.htm In retrospect, Mariner 10 did its job almost too well. composition, and unrav- It gave Mercury a geography and a history, even as it left eling Mercury’s internal The Mercury Chaser’s Calculator more than half the planet still unphotographed. Ironically, structure. Geologists www.fourmilab.ch/images/3planets/ elongation.html Mariner’s Mercury looked too Moon-like to make fin- anticipate that surface ishing the job seem urgent. Thus, as the 1970s drew to features will be imaged Messenger’s Mission Page a close, other planet destinations—chiefly Mars, Jupiter, at 125 meters or better messenger.jhuapl.edu and Saturn—made stronger claims on the limited bud- resolution. Global imag- NASA’s Planetary Photojournal (images) gets available, and Mercury was set aside. ing at 250 meters per photojournal.wr.usgs.gov/cgi-bin/ pixel will yield accurate PIAGenPlanetPage.pl?Mercury Two New Missions topography from stereo- After a quarter century, Mercury is back in the lineup, graphic pictures and BOOKS: with two missions in development. One is a $300 mil- laser altitude measure- Davies, Merton, Donald Gault, Stephen lion, US-built probe called MESSENGER (for MErcury ments. Dwornik, and Robert Strom. 1978. Surface, Space ENvironment, GEochemistry, and Spectrometers (infra- Atlas of Mercury. NASA SP-423. Washington, D.C.; Ranging). The other is the European Space Agency’s red, X-ray, neutron, and U.S. Government Printing Office. (ESA’s) BepiColombo. It is named for Guiseppe “Bepi” gamma ray) will map the Colombo, a now-deceased Italian planetary scientist mineral composition of Murray, Bruce, and Eric Burgess. 1977. who suggested to NASA how Mariner 10 could make the surface. Other instru- Flight to Mercury. New York; Columbia University Press. multiple flybys of Mercury. ments will sniff the flux MESSENGER comes from the Carnegie Institution of of particles from the Strom, Robert. 1987. Washington and Johns Hopkins University’s Applied Sun and hunt for those Mercury, The Elusive Planet. Physics Laboratory. Plans call for a launch in March sputtered off the surface. Washington, D.C.; Smithsonian Institution Press. 2004, followed by two flybys of Venus (June 2004 and Tracking the spacecraft March 2006) and two of Mercury (July 2007 and April and analyzing its radio Vilas, Faith, Clark Chapman, and 2008). The spacecraft arrives in Mercury orbit in April signals will tell about Mildred Shapley Mathews, eds. 1988. 2009, and the nominal mission lasts one Earth year Mercury’s gravity field Mercury. Tucson; University of Arizona Press. (four Mercury years). and the structure of its Multiple planet encounters make for a long journey but atmosphere. reduce the fuel the spacecraft needs. Nor is the cruise just After MESSENGER a snooze: instruments will be running during all four fly- comes BepiColombo, 9

THE PLANETARY REPORT JANUARY/FEBRUARY 2002 Right: BepiColombo, named for the late, beloved planetary scientist, Guiseppe “Bepi” Colombo, is still on the drawing board at the European Space Agency (ESA). Current plans for this ambitious mission include two orbiters and a lander, which will launch on two rockets in August 2009. Once they arrive at Mercury in October 2012, the orbiters will study the planet’s crust and magnetic field, while the lander measures the crust’s chemistry and mineralogy and, perhaps, samples the subsurface ice at the north pole. Illustration: European Space Agency

ESA’s more complex mis- face ice. The lander uses chemical rockets and an airbag to sion, still in the planning land and deploys a tethered microrover and a burrowing stage (and hence without a mole. (An alternative design features an impact penetrator final price tag). The current instead of the mole.) Above: The MESSENGER ( Mercury Surface, scenario calls for three sepa- Between MESSENGER’s primary mission (2009–10) Space Environment, Geochemistry, and Ranging) mission, scheduled for launch in rate probes. These are the and BepiColombo’s (2012–13) lies a gap in which March 2004, will carry a set of miniatur- Mercury Planetary Orbiter, MESSENGER results can help target BepiColombo’s ized instruments. The mission has been the Mercury Magnetospheric mission plan—and BepiColombo will seek to fill gaps designed to answer key questions about Orbiter, and the Mercury in coverage left by MESSENGER. Yet, both missions the planet’s crust, its high density and tectonic history. Scientists also hope to Surface Element. The last is fly independently, partly to ensure against one mission’s learn more about Mercury’s minimal a lander targeted for the failure dooming the other. atmosphere and magnetic field as well as northern polar regions. the nature of its mysterious polar caps. If all goes as planned, Bepi- A New Model of Mercury? Illustration: Johns Hopkins University Applied Physics Laboratory Colombo will be launched on Both missions have sophisticated questions to address, two rockets in August 2009. plus some basic ones left from Mariner 10. These include: In October 2012, after flybys • The surfaces of many planets and moons show marked of the Moon and Earth, differences between hemispheres—does Mercury’s also? Venus, and Mercury, the plan- • What is Mercury’s cratering history? Can Moon etary and magnetospheric rock dates help calibrate it? probes will brake into Mer- • When and how was Mercury volcanic? Do its rocks Mercury cury orbit while the lander vary much in composition? What explains their iron Data Download touches down. The orbiters deficiency? Diameter: have design lifetimes of an • Are the polar deposits water-ice? 4,880 kilometers (3,032 miles) Earth year or longer; the lan- • How much of Mercury’s core is molten? How does Mass: der, one week at a minimum. it generate a magnetic field with such a slow rotation? 3.3 x 1020 tons Each component has a spe- • Was Mercury born with a large core? Did a gigantic (Earth = 18.1 times greater) cific aim. The planetary or- collision strip off much of its crust? Or were the outer Uncompressed density: biter flies an orbit measuring layers vaporized by the young Sun’s activity? 5.3 (Earth = 4.1, water = 1.0) 400 by 1,500 kilometers (250 • What can Mercury tell us about the birth of rocky Albedo (reflectivity): by 930 miles) for detailed planets? 0.17 (lunar highlands = 0.11) studies of the surface with The modern era for Mercury began when Mariner 10 Average distance from Sun: cameras and spectrometers, flew by and found it a Moon-like body. Yet, as scientists 57.9 million kilometers while the magnetospheric learn more about our satellite, it increasingly appears to (36 million miles) craft follows a looping orbit be a special case by itself—and Mercury seems a lot Distance from Sun: some 400 by 12,000 kilome- more than merely a scaled-up Moon. Planetary scientists 0.387 AU (Earth = 1.0 AU) ters (250 by 7,500 miles). are now delving into these differences. They also want to Orbital eccentricity: This lets its instruments map fit the new Mercury into the evolving picture of the ter- 0.2056 (Earth = 0.0167) the magnetic domain from restrial planet family. This will finally let the little planet Year: 87.97 Earth days near Mercury to thousands of with the big iron heart take its proper place alongside Day: 58.65 Earth days kilometers out. And the lan- Venus, Mars, and Earth and its Moon. der, which may be sent to a shadowed polar crater, will Robert Burnham is the author or editor of several recent make in-place chemical and books on astronomy and earth science. His forthcoming mineralogical observations— constellation guide, Exploring the Starry Sky, will be 10 and perhaps tap into subsur- published in 2002 by Cambridge University Press.

THE PLANETARY REPORT JANUARY/FEBRUARY 2002 Above: This geologic map of Mercury, based on Mariner 10 images, was built to show surface rock types and their relative ages. Browns represent primitive crater, basin, and intercrater plains deposits. Blues depict crater and basin deposits (note the outline of Caloris Basin) from Mercury’s middle era. Pinks and reds stand for smooth plains deposits, probably volcanic in origin, from the planet’s middle and early eras, respectively, while greens and yellows show crater deposits from its youngest geological periods. The yellow swath covers an area for which no image data are available. Illustration: Paul Spudis, Lunar and Planetary Institute

Above: This color composite of Mercury’s surface was developed to highlight differences in certain soil compositions, origins, and ages. The shade of blue denoted by D represents enhanced levels of titanium. Primitive crustal material is shown as the bright yellow marked by B. Orange, shown by F, follows plains boundaries and is thought to be lava flow, while the lighter yellow of K indicates fresh subsurface material (which may have an unusual composition) around the crater Kuiper. Image: JPL/NASA. Reprocessed by Mark S. Robinson, North- western University, and Paul Lucey, University of Hawaii.

Left: A large portion of Mercury’s gray and pock- marked face is revealed by this shaded relief map, produced in 1979 from Mariner 10 images. Unfortunately, this was a face that bore too close a resemblance to Earth’s Moon to hold mission planners’ interest. In the past 25 years, however, scientists have amassed a collection of new questions about Mercury. With luck, two new missions to this rocky enigma will answer some of these questions. Map: United States Geological Survey, Flagstaff, Arizona

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THE PLANETARY REPORT JANUARY/FEBRUARY 2002 FROM THE EARTH TO MARS Part One: A Crater, Ice, and Life by Pascal Lee

Above: This topographic map of Haughton Crater and surrounding terrains is helping researchers recon- struct the glacial and erosional history of the site. Levels of elevations are represented by different colors in this digital elevation model, provided by the Geological Survey of Canada. The highest points (500 meters) surrounding the crater are shown as brown; the lowest are green. White and bluish-white indicate a possible stage of ice cover. Map: NASA/Haughton-Mars Project

Right: Just outside Haughton Crater lies Von Braun Planitia, the rocky polar desert landscape at Haynes Ridge. The rocks at this site are dominated by fossil- rich carbonates that are 350 to 400 million years old. This surface was exposed, following glacial retreat, only 8,000 to 10,000 years ago. The landscape pre- serves little obvious signature of glacial occupation or erosion. Previously glaciated terrains on Mars might likewise be difficult to A wide variety of terrain types are present at Haughton Crater. In some places, there are abrupt transitions from angular block fields to recognize. Intense frost fracturing caused the angular shape of these rocks, smooth, fine soils. The bright material in the distance is not snow but remnant deposits of the Haughton impact breccia melt sheet for- and the pits on the rocks are due mainly to carbonate dissolution from melting mation, once part of a vast pool of molten carbonates. Ice-covered Lake Sapphire (right) is the largest permanent lake inside Haughton ice and snow. Photo: Pascal Lee, NASA/Haughton-Mars Project Crater today. An isolated community of landlocked Arctic char (a troutlike fish) lives inside. Photo: Pascal Lee, NASA/Haughton-Mars Project

ar north in Nunavut Territory in the Canadian High kilometers around. A colossal shock wave expanded Arctic lies Devon Island, the world’s largest uninhab- through the ground as the impactor dumped its cosmic Fited island. Devon is home to one of the northernmost momentum into the Earth, blending into the target rocks impact structures on Earth, Haughton Crater. Measuring and vanishing as a superheated gas. The rocks themselves about 20 kilometers (12.4 miles) in diameter, it formed were crushed, melted, vaporized, pushed aside, and ejected. 23 million years ago when either an asteroid or a comet A cavity some 20 kilometers (12.4 miles) wide and 1.7 collided with our planet. At that time, during the Miocene kilometers (1 mile) deep appeared, only to grow shallow as epoch of geologic time, the climate was warmer. Boreal its unstable walls collapsed inward. Once the dust cleared, forests experiencing months of continual daylight fol- a smoldering hole with a vast pool of molten carbonate lowed by months of darkness covered the land. Among rocks appeared. Within seconds, Haughton Crater was born. the thick growths of conifers and birch trees roamed giant rabbits and small rhinoceroids (ancestral cousins to the A UNIQUE MARS ANALOG modern rhinoceros). Streams and lakes teemed with fish. My interest in the site began while I was still in graduate In an instant, things changed dramatically. A giant me- school, in the Department of Astronomy at Cornell Uni- teorite, perhaps 1 kilometer (0.6 mile) in diameter, plowed versity. I wondered if we could find an impact crater on into the scene. It may have happened in the broad daylight Earth that would be uniquely Mars-like, serving as a new of summer or in the bleak darkness of winter—we may “Mars analog.” Mars analogs are settings on Earth where never know. In either case, the impact, delivering an ener- environmental conditions, geologic features, biological gy equivalent to 100 million kilotons of TNT, would have attributes, or combinations thereof offer opportunities for produced a blinding flash of light, then a monumental air comparisons with possible counterparts on Mars and for 12 blast that obliterated almost all life for several hundred partial simulations of Martian conditions.

THE PLANETARY REPORT JANUARY/FEBRUARY 2002 art One: A Crater, Ice, and Life by Pascal Lee

The distinctive orange-colored mineral deposits on the rocks behind these Haughton-Mars Project team members are pipelike structures through which impact-heated water once flowed. Might similar structures be found at impact sites on Mars? Could such sites have supported life there, if only transiently? Photo: Pascal Lee, NASA/Haughton-Mars Project ton Crater. In some places, there are abrupt transitions from angular block fields to ce is not snow but remnant deposits of the Haughton impact breccia melt sheet for- es. Ice-covered Lake Sapphire (right) is the largest permanent lake inside Haughton Arctic char (a troutlike fish) lives inside. Photo: Pascal Lee, NASA/Haughton-Mars Project

No place on Earth is truly like Mars, so there is no such ies of the crater, but the Mars analog angle remained thing as the perfect Mars analog. But many partial analogs unexplored. I approached Chris McKay at NASA Ames do exist on our planet, and their study, with attention to Research Center (now a Planetary Society Board member) both similarities and differences between Earth and Mars, to do just that and, with his visionary support, obtained a may offer insight into the evolution of both worlds and of grant from the National Research Council to visit other planets as well. Haughton Crater. Antarctica is the coldest and driest continent on our A four-person team traveled to Devon Island in August planet and is in many ways of unique value to Mars analog 1997. Comprising the field team were James W. Rice Jr. studies. Yet, the continent possesses no positively identi- (then at NASA Ames, now at Arizona State University), fied impact structure. With Haughton Crater, the Arctic’s John W. Schutt (today, still the chief field guide for the US Devon Island offers the only terrestrial impact structure Antarctic Search for Meteorites program), Aaron Zent (of known to lie in a cold, relatively dry, windy, rocky, dusty, NASA Ames), and myself. The site proved interesting ultraviolet (UV) light–drenched (in the summer), and beyond our wildest dreams. We found not just one feature nearly unvegetated polar desert. From that standpoint, it that might serve as a potential Mars analog but several. promised to serve as a parallel to Mars. This initial reconnaissance led to what is today the Although conditions on Devon remain significantly milder NASA Haughton-Mars Project (HMP). The HMP is an than those prevailing on Mars (for instance, the average international, interdisciplinary field research project com- temperature on Devon is – 17 degrees Celsius, or 1 degree prising both a science program—which focuses on learn- Fahrenheit, versus – 60 degrees Celsius, or – 76 degrees ing more about Earth and Mars, impact cratering, and life Fahrenheit, on Mars), they are a step in the right direction. in extreme environments—and an exploration program Early research efforts at Haughton had focused on stud- looking to develop new technologies, strategies, and expe- 13

JANUARY/FEBRUARY 2002 rience with human factors that will help plan the future long ceased, but the hydrothermal sites are preserved in exploration of Mars and other planets by robots as well pristine condition, having been spared substantial weath- as humans. The present article focuses on the science ering under the increasingly frigid climate in the High program. A follow-up piece will cover the exploration Arctic since the Miocene. program. Understanding the nature, evolution, location, and preserved record of impact-induced hydrothermalism at THE CRATER Haughton helps us assess the biological potential of simi- It is hard not to imagine oneself on Mars when exploring lar sites on Mars as well as on other planets. Impact- Haughton Crater on Devon Island. induced hot springs would have been places where liquid In this wonderland, you can rove over thick deposits water and warmth would have coexisted, if only transiently. of fused impact debris and intracrater sediments laced They are places where life, perhaps imported from else- with ground-ice. While rocks on Devon are dominated where, might have gained a foothold and thrived. by carbonates, and Mars does not seem to possess large The Haughton Crater also once contained a lake or, quantities of these rock types, the physical properties more exactly, a network of water bodies whose shapes of impact deposits at Haughton are of interest. For evolved through time. This happened very shortly after instance, might the distribution of ground-ice in these the crater’s formation and might not have lasted more than deposits shed light on where to find ground-ice in im- a few million years. Although lake waters are long gone, pact-derived materials on Mars? Our ground-penetrating sediments that were laid down are beautifully preserved. radar surveys and shallow excavations at Haughton Indeed, Haughton’s paleo–lake beds represent the only Crater reveal that such substrates can hold massive sedimentary record of the Miocene preserved on our plan- amounts of ice (sometimes more than 80 percent by et in the Arctic. They provide the only snapshot we have volume), most occurring in the form of interstitial lens- of what the Arctic was like 23 million years ago. shaped concentrations micrometers to meters thick. It is in Haughton’s lake beds that our colleague Leo Haughton Crater also presents sites of ancient hydro- Hickey of Yale University and his collaborators found thermal activity once powered by the tremendous heat the remains of Miocene faunal and floral species. Bone is released at the time of impact. Evidence for these impact- not petrified but remains bone. Similarly, wood remains induced hot springs was only recently uncovered by the wood. Also, the fine, silty layering and its climate record HMP team. Gordon “Oz” Osinski, a graduate student in are hardly disturbed. Haughton’s intracrater lake beds geology from the University of New Brunswick, and his suggest that records of paleoenvironments might be well adviser, John Spray, are helping us reconstruct the geo- preserved in the sheltered setting of an impact crater on logic history of the crater. The impact-induced activity has Mars. Many craters there, whether or not they once

Left: Fine layers of ancient Right: This Viking orbiter lake bed sediments are still mosaic shows the small beautifully preserved inside valley networks of Maumee Haughton Crater. They were and Vedra Valles on Mars. deposited in a lake system (North is to the right.) On that occupied the impact Mars, networks span a crater shortly after its for- range of scales. These are mation 23 million years ago. among the largest—others The topmost part of the silty can be more than 100 times soil has been churned and smaller. disturbed by repeated cycles By (temperate) terrestrial of freezing and thawing. standards, the Martian However, within a depth of a valley networks look odd. couple of feet, the layering They maintain relatively has remained almost un- constant width and depth touched since the Miocene throughout, isolate big period. islands, and leave large Could there be ancient areas between their lake beds inside craters on branches, and between Mars, still preserving a networks, undissected. How record of the planet's past did they actually form? environments? The crater at bottom Photo: Pascal Lee, center is Crater Newport. NASA/Haughton-Mars Project Like Haughton, it is 20 kilometers (12.4 miles) in diameter and is transected by a valley. Image: JPL/NASA

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THE PLANETARY REPORT JANUARY/FEBRUARY 2002 harbored liquid water, are filled with layered deposits that the case of the Martian outflow channels, but in more might provide clues to past surface environments. modest trickles) after either localized rainfall, ground- In fact, the overall state of erosion at Haughton Crater water release, or mud flow. might be telling us something important about Mars. In These interpretations require a fairly warm climate for spite of Haughton’s young age compared with that of liquid water to flow at the Martian surface over distances many similar-size craters on Mars preserved since the end of tens to hundreds of kilometers without freezing. Such a of the Heavy Bombardment (a period of high impact rates conjecture has forced Mars climate modelers over the past early in the history of the solar system) about 3.5 billion decades to invoke increasingly elaborate mechanisms of years ago, and considering the relatively moderate ero- climate warming for early Mars, particularly given Mars’ sion, by terrestrial standards, that Haughton has been relatively great distance from the Sun, small planetary subjected to, the crater is less well preserved than the mass, the early Sun’s fainter light, and how impacts may majority of its Martian counterparts. This suggests that have stripped Mars of its early atmosphere(s). the cumulative effect of weathering and erosion on craters Devon Island is incised by a multitude of small valley of Haughton’s size on Mars over 3.5 billion years has networks that bear an uncanny morphologic resemblance, amounted to less damage than what Haughton itself has including in their bizarreness, to many of the small valley experienced over the past 23 million years in the Arctic. networks on Mars. The Devon networks formed neither by If Mars ever had a wet and warm climate over the past rainfall, groundwater release, nor mud flow but by the melt- 3.5 billion years, it was probably not for long. ing of vast ice covers that once occupied the land above the now-exposed surface. Sections of valley floors slant uphill THE ICE as one hikes downstream, indicating that some valleys are Many features outside Haughton Crater itself are also actually channels that formed by confined flow when melt- contributing to solving, and sometimes deepening, the waters gushed under a wasting ice cover. Because these mysteries of Mars. ancient ice sheets were very cold and mostly static, uplands Networks of channels found on Devon Island bear off to the sides of the channels were spared significant similarities to the so-called Martian small valley networks. glacial erosion. If anything, the ice cover protected them. Most of the latter date from the end of the Heavy Bom- So, is it possible that the many small valley networks on bardment, while some are also found on more recent ter- Mars are actually cold climate features instead of evidence rains, such as the flanks of relatively young volcanoes. that Mars once had a relatively mild climate? Might they The Martian small valley networks are classically thought have resulted from the subglacial melting of insulating ice to be the result of liquid water runoff flowing across the covers, which accumulated above the highlands and on Martian surface (not in the form of gigantic floods, as in the flanks of volcanoes when the ground was warmer and

Right: The National Geographic Society Network of small valleys on Devon Island appears in this image covering an area 4 kilometers (2.5 miles) across. These small valleys are comparable in morphology and scale to some of the smaller valleys seen in networks on Mars. Scientists think that glacial meltwater erosion is responsi- ble for these and similar networks on Devon. Some branches are partially filled with snow and ice. Note the relatively constant width and depth of the branches, the presence of steep-walled islands, and relatively large, undissected areas between branches and between networks. Air photo: Geological Survey of Canada. Image processed by NASA/Haughton-Mars Project. 15

THE PLANETARY REPORT JANUARY/FEBRUARY 2002 water more readily recycled to the surface by impacts and images of Mars reveal the presence in many locations active volcanism—though in a frigid climate? Might (mostly at high latitudes but also elsewhere) where Mars have been cold climatically throughout most of its similar-looking features occur. One implication is that history, with liquid water at most a local and transient ground-ice might have been abundant near the Martian phenomenon at the surface? surface when the features formed. Given how fresh The mighty canyons of Devon Island might, indepen- some of these features look today, might ground-ice dently, reinforce this picture. They seem to have specific still be present at their locations on Mars? morphologic counterparts on Mars, in particular the broad, winding V-shaped valleys of Ius Chasma in LIFE AT THE EDGE western Valles Marineris. Some believe the latter Devon Island is also astonishing by the resilience of its formed by sapping—that is, the slow release of ground- life. Life in the polar desert persists at the edge. Liquid water accompanied by progressive “headward” erosion water is rare and so are nutrients. Our studies of microbial of rocks in the direction of the source. The canyons on life at Haughton, led by HMP Chief Biologist Charles Devon, however, are the result of glacial erosion (the Cockell of the British Antarctic Survey, are revealing carving done this time by ice, not meltwater, as in the stories of survival and adaptation that might have implica- case of the island’s channel networks). Might their tions for our search for life on Mars and elsewhere. counterparts on Mars result from glacial carving as well? For instance, in spite of the high UV radiation environ- While not settling the mystery of past climates on ment prevailing in the High Arctic during the summer, Mars, our work on Devon Island is offering new inter- with its 24 hours of unrelenting sunlight, microorgan- pretations for many of the Red Planet’s so-called fluvial isms are able to avoid radiation damage and indeed landforms. Our research suggests that surface ice thrive by remaining shielded. Many do so simply by deposits have played a much greater role throughout colonizing sheltered areas underneath rocks or in soils. Martian history than classically suspected. But others, such as algal mats living at the bottom of On another front, the ubiquitous presence of ground- open, shallow ponds and puddles, have evolved natural ice near the surface in the Arctic is visible, if indirectly, sunscreens. Like humans donning a spacesuit allowing across the landscape on Devon. Terrain features such as them to survive in an otherwise lethal environment, rock glaciers, ice-cored mounds, polygons, rock circles, these microbial colonies coat themselves with a secreted rock stripes, and myriad other forms of “patterned gelatinous, pigment-rich UV-screening compound form- ground” abound. Such features are the trademark of ing a protective biofilm. Long after the microorganisms periglacial processes, or processes shaping the land- themselves have died, such biofilms can remain intact, scape in environments that are rich in ground-ice. designed as they are to withstand weathering. Should Viking orbiter and Mars Global Surveyor (MGS) the search for past life on Mars therefore involve a

Inset: This detailed segment of a Viking Orbiter mosaic shows a broad, winding canyon branching into Ius Chasma in western Valles Marineris on Mars. Notice the canyon's V-shaped pro- file, stubby tributaries, and the undissected surround- ing upland plateau. The widest point in this valley is 20 kilometers (12.4 miles). Might such valleys have formed not by sapping (the classical hypothesis) but by glacial erosion? Image: JPL/NASA

Right: Devon Island also has a V-shaped winding canyon with stubby tributaries and relatively undissected sur- rounding uplands. The widest point in this valley is 2 kilometers (1.2 miles) wide. Geologists interpret this feature to be a glacial trough valley formed through erosion by a fast-moving ice stream flowing from a vast, otherwise static ice cap that once covered Devon at this Above: This intricate maze of canyons on site. Air photo: Geological Survey of Canada. Image processed by Devon Island is also interpreted as having NASA/Haughton-Mars Project. formed by glacial erosion. Photo: Pascal Lee, NASA/Haughton-Mars Project 16

THE PLANETARY REPORT JANUARY/FEBRUARY 2002 search for resistant biocompounds that putative micro- MGS) have been found on the island and are currently organisms might have evolved to survive in the planet’s being studied in detail. Rather than involving significant harsh, UV-drenched, near-surface environment? groundwater seepage or even ground-ice melting (prevail- At Haughton, we have also found that the inside of the ing hypotheses for the Martian gullies), the features on crater’s battered rocks can host enhanced colonization Devon appear to be due mainly to the repeated melting, by cyanobacteria. Endolithic microbial communities year after year and possibly glaciation after glaciation, of (microbes living inside rocks) are not new. They were transient deposits of surface snow and ice. Might snow first reported by Imre Friedmann in sandstones from the and ice deposits have formed and melted on Mars in Antarctic Dry Valleys more than two decades ago. But recent times, perhaps as a result of short-term obliquity until now, they had not been reported in crystalline rocks, (tilt) swings of the planet? Might there be microbial life which are typically very compact and opaque, only in close to the Martian surface today? more porous and translucent sedimentary rocks. At In the end, it may be difficult to ever understand Mars Haughton Crater, however, crystalline rocks have been without exploring it in situ. And even then, it might be so heavily fractured and rendered porous that they are impossible to resolve some mysteries, as may be the case now home to thriving colonies of cyanobacteria. here on Earth. But our studies in the Arctic are increasing This finding shows that impacts are not necessarily bad our understanding of our own planet as well as helping news for life. While they might threaten highly evolved look at another world with new insight. It is part of the and narrowly adapted organisms such as dinosaurs and journey from the Earth to Mars. mammals, impacts could have offered microbial life shelter and warmth when needed most—that is, on early Pascal Lee, a planetary scientist at the SETI Institute, is Earth and possibly early Mars. In addition, impacts are based at NASA Ames Research Center in Moffett Field, capable of launching rocks from one planet to another. California. He is the project lead and principal investi- Thus, not only do impacts serve as Nature’s interplanetary gator for the NASA Haughton-Mars Project on Devon launch mechanism, they might also create suitable lithic Island, Nunavut, Arctic Canada. vessels for the successful transfer of microbial life. For more information on the NASA HMP, visit THE JOURNEY CONTINUES www.marsonearth.org. Summer after summer, the geologic and biologic wonders of Devon Island and Haughton Crater continue to surprise us. Gullies eerily similar in both morphology and context to those recently reported on Mars by Mike Malin and Ken Edgett (operators of the Mars Orbiter Camera on

Mars Global Surveyor's Mars Orbiter Camera returned this image of a fresh- looking gully system on Mars on July 14, 1999. (See the September/October 2000 issue of The Planetary Report for more details.) Image: NASA/JPL/Malin Space Science Systems

This gully system on Devon Island is similar in morphology, scale, and context (they usually form along the cold, north-facing walls of valleys) to some of the recent gully systems reported on Mars. The gullies on Devon result from the repeated melting, year after year, of seasonal snow or surface ice patches that accumulate and linger in the nooks and crannies of rocky bluffs along the top part of canyon walls. Could the gullies on Mars have formed not by the prevailing hypotheses of groundwater seepage or ground-ice melting, but by a mechanism similar to that observed on Devon Island? Photo: Pascal Lee, NASA/Haughton-Mars Project 17

THE PLANETARY REPORT JANUARY/FEBRUARY 2002 World

Watch by Louis D. Friedman

Edinburgh, UK—The science to rendezvous with Ceres and Vesta, the to Congress. Although it included a ministers responsible for space funding most massive known asteroids in the solar remarkable 19 percent increase in space in the member countries of the Euro- system. These two main-belt objects are science, funds for the development of pean Space Agency (ESA) met in Edin- very different from each other, but both the space station were severely cut, burgh to set the agency’s budget and hold clues to the origin and evolution of while cancellation of the development programming. the solar system. Dawn is also sched- of current Pluto–Kuiper Belt and Next year, ESA will launch two mis- uled for a 2006 launch, with the Vesta Europa orbiter missions was proposed sions: Mars Express and Rosetta. Mars rendezvous planned for 2010–11 and in favor of a future line of planetary Express, which includes both an orbiter the Ceres rendezvous for 2014–15. The missions called New Frontiers. and the Beagle 2 lander, will reach its mission is managed by Christopher The major new initiative proposed target in late 2003. Rosetta will rendez- Russell of UCLA and supported by the was development of space nuclear vous with comet Wirtanen in 2011 and Jet Propulsion Laboratory. power and propulsion. The large Mars land in 2012. ESA is also a major play- rover being planned for 2007 is now er in the Cassini mission, having built Puerto Rico—In late December, delayed for a 2009 mission in order to the Huygens probe that will descend NASA announced plans to curtail all take advantage of the nuclear power through Titan’s atmosphere in 2005. radar science from Arecibo, the technology, which will make possible As a result of the Edinburgh meeting, world’s largest radio telescope. One of long lifetimes and range. the European ministers supported an the primary goals of such science was O’Keefe cited the advantages of ESA science program that includes de- accurate determination of orbits and nuclear electric propulsion for a later velopment of a Mercury orbiter. They sizes of near-Earth objects (NEOs). Pluto mission, which could theoreti- also provided a 14.1-million-euro budget NASA’s action was taken as a budget- cally arrive around the same time as for a three-year project known as Aurora. saving device. Congress had mandated the currently planned mission because The Aurora team will develop a long- a NEO discovery program with the goal of the shorter travel time. That assumes, term plan for robotic and human explo- of finding 90 percent of objects larger however, a relatively quick and straight- ration of the solar system, including the than 1 kilometer (0.6 mile) in diameter forward development of the nuclear search for extraterrestrial life. The fund- by 2008. Funding the program made electric capability. ing for both the Mercury mission and less money available for the follow-up This is the third time that cancellation Aurora was less than ESA requested, work of tracking and characterizing the of the Pluto mission has been proposed. however, and the ministers refused to objects. Yet, the dangers of limiting Each time, Congress has intervened to grant any increase to the science budget our knowledge of approaching NEOs restore it. The Planetary Society has above inflation. Consequently, ESA became readily apparent. The Planetary strongly advocated the mission, and officials say the Mercury mission may Society, in collaboration with the plane- while we welcome the new initiatives have to be scaled back or delayed. Also, tary science community, took a strong and solid support for planetary explo- a more aggressive Mars exploration public stand against the decision. With- ration in the budget proposal, we op- program under the Aurora plan failed in 24 hours, NASA reversed its position. pose the proposed cancellation. How to materialize. It has now agreed to review the entire this will all play out in Congress will project with an eye to maintaining the be determined in the next few months. Washington, DC—NASA has radar observation program. Visit our website, planetary.org, to selected two more planetary Discovery keep up-to-date on political decisions missions. Kepler, the first spacecraft Washington, DC—NASA affecting planetary exploration. As devoted to the search for planets around launched into 2002 with a new admin- with our efforts on behalf of the Mars other stars, will be launched in 2006. istrator, Sean O’Keefe. O’Keefe had program two years ago, the Pluto mis- Using a 0.95-meter telescope from a been deputy director of the Office of sion last year, and, most recently, the heliocentric orbit, Kepler will estimate Management and Budget (OMB) in the Arecibo radar program, we can make the number of planets around other Bush administration, leading efforts to a difference. stars. The NASA Ames Research Center constrain funding on the space station. project will be led by William Borucki. As we went to press, Bush’s fiscal year Louis D. Friedman is executive director 18 Dawn is an asteroid mission targeted 2003 budget proposal was submitted of The Planetary Society.

THE PLANETARY REPORT JANUARY/FEBRUARY 2002 The Shoemaker NEO Grants— 2002 It’s Time to Propose!

BY DANIEL D. DURDA

he Planetary Society is now accepting proposals for Tthe next round of Gene Shoemaker NEO Grants, which continue to make possible the valuable scien- tific work of detecting, tracking, and characterizing asteroids and comets in the near-Earth environment. The Shoemaker NEO Grant program was initiated by The Planetary Society in 1997 in honor of planetary geologist Eugene Shoemaker, who pioneered our understanding of asteroid and comet impacts on Earth. The founding goal of the Shoemaker NEO Grant program was to increase the rate of discovery and follow-up study of NEOs (near-Earth objects) by providing dedicated amateurs and observers in developing countries with seed money to increase their con- tributions to critical NEO research. Indeed, by awarding grants to nearly a dozen recipients in countries spanning the Lights twinkle globe, Planetary Society members have helped support tions require the use of modest-size telescopes. Phenomenal on an unsus- pecting Earth tremendously important NEO search and recovery efforts advances in telescope, camera, and computer technology in moments be- that would have otherwise lacked adequate funding. recent years have placed professional-quality instrumenta- fore a devas- Large search programs like LINEAR, LONEOS, NEAT, tion in the hands of many capable amateurs. For example, tating asteroid and Spacewatch, which are funded primarily by the US observers utilizing thinned-chip CCD cameras on telescopes impact. To increase our government through NASA, are certainly doing a good job with apertures larger than 0.3–0.4 meter (12–16 inches) chances of of meeting the Spaceguard goal of finding 90 percent of the can make a useful contribution to NEO research. In fact, spotting an kilometer-and-larger near-Earth asteroids (NEAs) by the inspection of the Minor Planet Electronic Circulars unwelcome year 2008. announcing new NEOs shows that the best amateur contri- visitor ahead of time, The Although we are discovering NEAs at about two-thirds bution to astrometric follow-up observations currently Planetary the rate needed to meet that goal, the best estimates are that comes from a group regularly using a 0.75-meter (30-inch) Society's Gene we have already discovered about half the roughly 1,000 telescope. Facilitating more contributions from groups like Shoemaker NEO Grant NEAs 1 kilometer (0.6 mile) and larger that roam the inner this, particularly in the Southern Hemisphere, is what the program solar system. While planetary scientists continue to make Shoemaker NEO Grant program is all about. awards fund- great strides toward determining the number of potential The Shoemaker NEO Grant’s panel of internationally ing to amateur Earth-impacting objects, much work remains to be done. recognized NEO researchers will consider proposals for astronomers who perform The major survey programs are expensive to operate, and projects that can enhance the rate of follow-up of faint observations after allocating funds among them, the government has lit- NEOs or help advance our knowledge of the physical prop- of recently dis- tle, if any, money left to support vital astrometric follow-up erties of NEOs. The selection committee will be looking for covered NEOs. and physical characterization observations. Astrometric “leveraged” proposals rather than projects solely supported Illustration: follow-up (precise observations of the positions of objects in by Shoemaker NEO Grant funds. Leveraging could include Chris Butler the sky) defines accurate orbits for newly discovered NEOs upgrading an existing facility, matching funds from other so that their paths can be tracked into the future to check for sources, procuring specific hardware items (such as a potential Earth impacts. Physical characterization (determin- thinned-chip camera), and so on. ing the size, rotation, and composition of objects) allows Applications are due April 1, 2002 and will be considered scientists to understand the material properties of NEOs so from anyone, anywhere. Three to seven grants will be that the stuff that formed the planets can be studied and awarded, with average grant amounts ranging from $3,000 impact hazard mitigation strategies developed. to $10,000. The awards will be announced in June 2002. Here is where smaller programs funded by The Planetary For further information and instructions for completing a Society’s Shoemaker NEO Grants can play a major role. With proposal application, visit the Society’s NEO website at more and more NEOs being discovered every month, all the www.planetary.org/html.neo. necessary follow-up and physical study observations are overwhelming professional astronomers. The need, then, is Daniel D. Durda is a planetary scientist at the Southwest for programs that can follow up and observe NEOs that are Research Institute in Boulder, Colorado, where he studies the fainter than magnitude V = 19.5 or so (about 400,000 times collisional evolution of asteroids. He is also the coordinator fainter than can be seen with the naked eye). Such observa- for The Planetary Society’s Shoemaker NEO Grant program. 19

THE PLANETARY REPORT JANUARY/FEBRUARY 2002 Questions and AnswersAnswers

Why do only the gas giants have rings, a moon. Likewise, rings disappear as gambler who started with a certain while the rocky planets have none? their ring particles are ground down by stake (its original retinue of small —J. HOWARD, collisions and swept away by frictional moons). The rocky planets have all Halifax, Nova Scotia drag. Friction from gas, from charged lost their stacks of chips, leaving only particles around the planet, and even the giant planets, which still have Planetary rings are made of myriad from sunlight slows the ring particles their families of small moons (the small particles in orbit around a planet. in their orbits—they are swept away raw material for rings) as players in We cannot see them individually but and leave the ring system or burn up the “ring creation” game. only collectively—like the droplets of in the atmosphere the way Skylab did. —LARRY ESPOSITO, water in a cloud, they reflect the Sun’s The balance between these acts of cre- University of Colorado light. Rings are found only close to ation and destruction yields the rings their parent body, where the planet’s we see today. I’ve read that half the stars we see gravity is strong enough to overcome Mars may have very tenuous rings are binary stars. Could these double the ring particles’ tendency to stick made of dust blasted off its moons stars have solar systems similar to together and grow into a small Phobos and Deimos. After the giant our own, or would the orbits of their moon—the same way the planets coa- impact that created our Moon, Earth planets be radically different? lesced around our Sun when the solar temporarily had a ring—before the Also, are the odds for finding life system formed. Moon went on to consolidate into a in binary-star systems greater than Planetary rings are transient. They single body. in single-star systems? are created either continuously from Maybe every planet had rings once —LEE VAUGHAN, dust knocked off small satellites by in its history. Rings represent random The Woodlands, Texas meteoroid bombardment or episod- events that are unpredictable. Think ically, as when a comet smashes into of it this way: each planet is like a At least half the stars one sees at night are members of binary- or multiple- star systems. As our ability to detect This series of Hubble Space Telescope (HST) unseen companions to stars improves, images, captured from 1996 to 2000, depicts the number of known binary- and Saturn's rings from just past edge-on to multiple-star systems can only in- nearly fully open. Although the planet is crease. Because each binary or multi- 120,000 kilometers (75,000 miles) across, its rings are only about 10 ple system consists of two or more meters thick. Constant disruption stars, only a minority of the total from the planet's gravitational number of stars in our galaxy are field causes the rings to single stars like our Sun. Therefore, spread out instead of form into a moon. it is natural to wonder about the likeli- Image: NASA/HST hood of habitable planets in binary- and multiple-star systems. Unfortunately, there is no definitive answer to your question at this time, because we do not understand how the planet formation process proceeds in a binary- or multiple-star system. Most theoretical studies on planet formation have been devoted to un- derstanding the genesis of our solar system—with mixed results. While scientists generally agree on the basic formation mechanism of terrestrial planets, there is much more contro- 20

THE PLANETARY REPORT JANUARY/FEBRUARY 2002 versy surrounding the formation of in which binary systems an Earth-mass binary star pair would be too cold for the gas and ice giants. planet could have a stable orbit, re- habitability unless the stars were very Preliminary studies on the forma- gardless of how it formed. Generally luminous. The other half remain viable tion of terrestrial planets through col- speaking, for an Earth-like orbit candidates—in fact, ground-based lisions between planetesimals (small around a star like the Sun to be stable, extrasolar planet searches have bodies that will evolve into planets) any binary star companion to that sun already discovered Jupiter-mass plan- suggest that having a binary star com- would have to be on an orbit at least ets in orbit around several stars with panion may well accelerate planets’ as distant as that of Jupiter, depend- binary companions on wide orbits. growth processes and lead to a new ing on the binary companion’s mass NASA’s recently approved Kepler type of runaway growth in which and orbital shape. mission will be able to assess the fre- colliding orbits are created more by About half of all binary stars are quency of Earth-like planets around gravitational pulls from the binary separated by distances less than the a large sample of both single and companion than from nearby plan- Sun-Jupiter distance, so these binary binary stars, providing the ultimate etesimals.This is an important ques- stars would not be good candidates answers to your questions. tion for ongoing theoretical study. for extrasolar Earths; stable planetary —ALAN P. BOSS, Another approach is to determine orbits at large distances from a close Carnegie Institution of Washington

Factinos

planet has been discovered in eep below the surface of the wo hundred fifty million years A orbit around the giant star Iota DBeaverhead Mountains of Idaho, a Tago, something unknown wiped Draconis, located 100 light-years from research team led by Derek Lovley of the out most life on our planet. Now, Earth in the constellation Draco. This University of Massachusetts and Francis inside tiny capsules of cosmic gas, is an especially important finding H. Chappelle of the United States Geo- scientists are finding clues to this mass because it provides insight into the logical Survey has found an unusual extinction. fate of planets during the late life community of microorganisms. This Luann Becker of the University of cycles of stars. community may help us understand how California, Santa Barbara led a team The discovery was announced in life could survive on Mars. The team’s of scientists to sites in Hungary, Japan, January 2002 at the American Astro- findings are spelled out in the January and China where 250-million-year-old nomical Society in Washington, D.C., 17, 2002 issue of Nature. rocks can still be located. There, the by Sabine Frink, David S. Mitchell, and “The microbial community we found in team found telltale signs of a collision Andreas Quirrenbach of the University Idaho is unlike any previously described between our planet and an asteroid 6 of California, San Diego; Debra A. on Earth,” said Lovley. “This is as close to 12 kilometers (3.8 to 7.4 miles) Fischer and Geoffrey W. Marcy of the as we have come to finding life on Earth across—as big as or bigger than Mount University of California, Berkeley; and under geological conditions most like Everest. Paul Butler of the Carnegie Institution those expected below the surface of Mars. Below a certain point in the accumu- of Washington. This study demonstrates, for the first lated layers of earth, the rock the team What makes the discovery remarkable time, that certain microorganisms can studied shows signs of an ancient world is that the host star is not a Sun-like star thrive in the absence of sunlight by using teeming with life. In more recent layers but an old star that has already burned hydrogen gas released from deep in the just above that point, signs of life all the hydrogen fuel in its core. Such Earth’s surface as their energy source.” but vanish. “giant stars” grow much bigger toward “Over 90 percent of the microorganisms Scientists call this event, which the end of their lives, and Iota Draconis were Archaea, which are microorganisms occurred at the boundary between the has expanded to a radius that is 13 considered to be most closely related to Permian and Triassic periods, “The times the radius of the Sun. ancient life on Earth. In this case, the Great Dying”—not to be confused with “Until now, it was not known if Archaea were methane-producing micro- the better-known Cretaceous-Tertiary planets existed around giant stars,” says organisms that live by combining hydro- extinction that signaled the end of the Frink. “This provides the first evidence gen with carbon dioxide to make methane dinosaurs 65 million years ago. What- that planets at Earth-like distances can gas. They do not require organic carbon ever happened between the Permian survive the evolution of their host star in order to grow,” Lovley explained. and Triassic periods was much worse, into a giant.” Now that such a microbial community as life on our planet almost came to —from the University of California, has been found, Lovley added, scientists an end. Berkeley can test hypotheses about hydrogen- —from NASA Science News based subsurface life. They also can de- velop strategies for searching for similar microbial communities on other planets. —from the University of Massachusetts 21

THE PLANETARY REPORT JANUARY/FEBRUARY 2002 Society News

Generous Donation to would like to gratefully acknowl- led by Ann Druyan, has supported the Cosmos 1 Project edge Getzman, as well as the fol- the largest project: the Cosmos 1 The Planetary Society is honored lowing for their generous bequests solar sail. The LEGO company has to announce a donation of to the Society in 2001: George joined with us to create the first $750,000 made by Peter Lewis to Carey, Jonathan Kamin, and Robert student exploration project that the Cosmos 1 solar sail project. Gibson. will go to another world: Red Rover The gift, secured by Society Board For more information on making Goes to Mars. member and Cosmos Studios CEO bequests to the Society, call Lu We also acknowledge the support Ann Druyan, provides valuable Coffing at (626) 793-5100, exten- and leadership of the New Millen- additional funds for the project. sion 234, or e-mail her at lu.coffing nium Committee as well as major Cosmos Studios is the chief spon- @planetary.org. individual donors who helped the sor, along with the Arts and Enter- —Lu Coffing, Financial Manager Society last year, including David tainment Network, which will Brown, Don Cline, Manuel Cortes, broadcast a documentary on the Use PayPal and Cosimo DiBella, Raymond Frazier, making of the mission. Double Your Donation Christopher Fulton, Dan Geraci, This is the largest donation in our The Life to Mars Foundation has Irene Gleason Jordan, Jack Lasee, history and represents not only an pledged to match donations made Bill Nye, Ray Olszewski, Harvey important financial contribution to The Planetary Society on our Schussler, Stephen L. Shields, John but also a new step in public partici- website through PayPal, the world’s Tricou, and Akira Urita. —LDF pation in space exploration. A bold, leading Internet payment system. pioneering venture in science and Life to Mars is an organization that Annual Audit technology, Cosmos 1 is financed seeks to further the establishment Completed entirely by the private sector. of a self-sustaining human base on The firm of Hensiek & Caron has Lewis is the former chairman the Red Planet. Elon Musk, chair- completed its yearly audit of The and CEO of Progressive Insurance man of the Life to Mars Foundation, Planetary Society. The firm deter- Co. A philanthropist as well as a is a director and founder of PayPal. mined that the Society’s 2001 leader in the art community, he We encourage members to use financial statement was in confor- chairs the Board of the Guggen- our website for all member services. mity with generally accepted heim Museum of Art in New York If they wish to make a donation or accounting principles. Copies of and is a major contributor to Case dues payment with PayPal, they the financial statement are avail- Western Reserve University and to will know their gift will be doubled able upon request. —LC Princeton University. We gratefully by the Life to Mars Foundation. acknowledge his donation. —LDF Another Expedition? —Louis D. Friedman, Interested in accompanying us on Executive Director We Thank our next expedition? We are con- Our Supporters sidering traveling to Argentina to Surprise Bequest Besides needed funding, support study some intriguing outcrops in Helps Society from nonmembers as well as mem- Patagonia in January/February 2003. We are very pleased to note a bers adds to the positioning of the The expedition is still in the initial remarkable bequest to the Society Society as an important representa- planning stages, so details are not from nonmember John Getzman. tive of public interest. In addition yet available. If you’re curious and His bequest, like others from non- to the individuals already cited, we want to be added to a list for up- members in our history, testifies to wish to acknowledge two corporate dates, call Lu Coffing at (626) 793- The Planetary Society’s growing sponsors who have made new ven- 5100, extension 234, or e-mail her impact beyond even our large tures possible. Cosmos Studios, the at [email protected]. 22 membership. The Board and staff exciting new science media venture —LC

THE PLANETARY REPORT JANUARY/FEBRUARY 2002 INSPIRATIONINSPIRATION FOR FOR THE THE NEW NEW YEAR! YEAR!

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Adriaen Collaert (1560-1618) was a Flemish draftsman, en- graver, print publisher, and deal- er from Antwerp, Belgium. He produced an extensive oeuvre of engravings of the natural world, depicting flowers as well as birds, fish, and other animals, along with a series featuring the four elements of Classical thought: earth, fire, water, and air. Reprinted by permission from the Fine Arts Museums of San Francisco, Achenbach Foundation for Graphic Arts 1963.30.15383

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