San Diego Astronomy Association Celebrating Over 40 Years of Astronomical Outreach

Office (619) 645-8940 August 2011 Observatory (619) 766-9118 http://www.sdaa.org August Program Meeting A Non-Profit Educational Association P.O. Box 23215, San Diego, CA 92193-3215 Date: August 17th Speaker: Jerry Hilburn SDAA Business Meeting Topic: JUNO - A NASA New Frontiers mission to the Next meeting will be held at: planet Jupiter 3838 Camino del Rio North Scheduled to launch in August 2011 aboard an Atlas V Suite 300 rocket the spacecraft will be placed in a polar orbit around San Diego, CA 92108 Jupiter to study the planet’s composition, gravity field, August 9th at 7pm magnetic field, and polar magnetosphere. Jerry Hilburn will discuss the mission details, science objectives, and answer Next Program Meeting questions about the mission. August 17, 2011 at 7pm San Diego Astronomy Association (SDAA) sponsors Mission Trails Regional Park speakers on a wide range of astronomy topics on the third Visitor and Interpretive Center Wednesday of every month at the Mission Trails Regional 1 Father Junipero Serra Trail Park Visitors Center. The Program meeting begins at 7:00 PM. Each attendee receives one free door prize ticket. After announcements and a small amount of business, the au- dience is treated to the featured presentation. At the close of the meeting the door prizes CONTENTS are presented. The event is open to the public. The Mission Trails Regional Park Visitors August 2011, Vol XLIX, Issue 8 Center is at One Fr. Junipero Serra Trail, San Diego CA 92119. Call the park at 619-668- Published Monthly by the 3281 for more information or visit http://www.mtrp.org. San Diego Astronomy Association Please contact Bill Carlson ([email protected]) if you have an questions, com- $2.50 an issue/$30.00 year ments, or ideas for the Program Meetings. Incorporated in California in 1963 August Program Meeting...... 1 Rilke & The Horse & Rider...... 1 RILKE & THE HORSE & RIDER By John Mood SDAA Membership Dues...... 2

July Minutes...... 2 For just a few more weeks now Ursa Major (& its asterism the Big Dipper) will be up Julian Starfest 2011...... 4 for viewing before it begins to sink into the sky glow & haze in the west. Which means Summer in the City...... 4 that one of the most intriguing naked eye double is still available. It is the middle SDAA Contacts...... 8 in the handle of the Big Dipper. Actually it’s 6 stars, 2 of which are visible naked August Calendar...... 9 eye, a third available in telescopes, & spectroscopy reveals that each of these 3 stars is a ASIG Gallery...... 10 double. The 2 visible ones have for more than 1000 years been known (to the Arabs) as The Back Page...... 12 Mizar & Alcor, the Horse & the Rider. Last month I introduced you to the German-language poet Rainer Maria Rilke (1875- 1926), who has more poetry on the night and the night sky than any other. He always makes sure his information is scientifically accurate. Here’s what he says about these 2 stars as I describe in a book of mine: Rilke twice in his poetry refers to the dim naked eye double star commonly known as Newsletter Deadline the “Horse” and the “Rider.” This double star is the middle one of the three which make The deadline to submit articles up the handle of the Big Dipper. [. . .] The “Horse,” the brighter star of the double, is for publication is the more precisely named “Mizar” and its technical astronomical designation is Zeta Ursae 15th of each month. Majoris; the “Rider,” the dimmer star, is named “Alcor” and is technically known as 80 Ursae Majoris. This lovely sight is easy to find if one is far away from city lights, knows exactly where San Diego Astronomy Association to look, and has good young eyes! The “Horse,” as mentioned, is significantly brighter than the other snuggled up quite close to it, the “Rider,” which is much more difficult to spot, requiring good vision and very dark skies. It is obvious that Rilke had often gazed upon both stars, illustrating his ubiquitous emphasis on “inseeing.” Rilke’s critics always interpret his “inseeing” symbolically; it never seems to occur to them that he meant it quite literally to begin with. Go gaze at the star itself! Yes indeed. Go gaze at it yourself! To do so naked eye, you’ll have to get away from the sky-glow of the San Diego metropolitan area, let your eyesight get dark-adapted, & have young eyes! I used to be able to see it easily, but today these dimmed eyes of my dotage require me to use binocs to see the double. In any telescope, one discovers that Mizar is a neat double star itself, one of mag 2.5, the other of 4.0, easily split. Between Mizar & Alcor is another star, not related to the others, so you’ll see 4. As said above, all 3 stars are spectroscopic doubles & are gravitationally related, meaning they are a 6-star system drifting through space. Incidentally, Rilke’s two uses of the “Rider” occur near the end of his great long lyric poem Duinese Elegies and in Part I, poem 11, of his sequence The Sonnets to Orpheus.

{From A New Reading of Rilke’s “Elegies”: Affirming the Unity of “life-AND-death” (Lewiston, NY: Edwin Mellen Press, 2009), p. 80. Also in Rilke on Death and Other Oddities (Philadelphia: Xlibris Corp., 2007), pp. 80f., with photo.} SDAA Membership Dues Increase by Michael Vander Vorst, President

Effective November 1st, the yearly cost of a contributing SDAA membership will increase by $10 and the cost of basic member- ship will increase by $5. The dues for additional family members remains the same, and the annual lease cost of the private pads will also increase by $10. This is the first dues increase in nearly a decade. Now for the good news, membership in SDAA remains an incredible value. As a contributing member you get unlimited use of our dark sky site at Tierra del Sol (TDS) and, once trained, use of the 22-inch Lipp telescope. The primary reason for the increase is to maintain and improve TDS: we are procuring a new storage container at TDS - just for loaner scopes; we will be making additional repairs to the warming room by adding new drywall, insulation and paint, as well as painting the Lipp observatory; yearly maintenance on the roadways and pad areas at TDS requires tons of gravel; we will build a new electronics shed by the roboscope; the roboscope software and hardware will be upgraded so that it can be easily used by club members for remote imaging, not just asteroid searches; and the cost of printing and mailing the newsletter is ever increasing. We on the board of directors did our best to balance the need to make TDS a great dark site and yet keep the dues reasonable. The improvements to TDS are ongoing and we hope you will take advantage of this tremendous resource. SDAA Board of Directors Monthly Business Meeting Minutes 12 July 2011

1. Call to order. The meeting was called to order at 7:06 pm with the following board members in attendance: Michael Vander Vorst, President; Bill Carlson, Vice President; Ed Rumsey, Treasurer; Jeff Herman, Corresponding Secretary; Mike Finch, Director; Kin Searcy, Director; Scott Baker, Director; Bob Austin, Director. Members in attendance were John and Andrea Kuhl, and Paul “Moose” Pountney. 2. Approval of Last Meeting Minutes. Approved 3. Priority / Member Business. None 4. Standard Reports. Treasurer’s Report. Approved. D & O insurance was the only significant expense. Membership Report. Up seven for a new total of 540. Site Maintenance Report. • The next site cleanup will take place the week before the picnic in September. • We’ll remove the damaged drywall and insulation in the warming room after the small observatory is moved into the storage container Observatory Report. No report Page 2 SAN DIEGO ASTRONOMY ASSOCIATION NEWS AND NOTES, AUGUST 2011 San Diego Astronomy Association

Private Pad Report. • The newest round of private pad offerings has closed and we sent out the offers. The lease effective date is 7/11/11 pending receipt of the signed leases and payment. There were 11 people on the waiting list, 3 declined to be included in this round for various reasons, and 3 did not respond. Every member got either their first or second choice of pad. The new pad holders are: 1. Scott Atwood (Pad 46) 2. John Hardin (Pad 62) 3. Doug Coe (Pad 69) 4. Miguel Cravo (Pad 12) 5. Tim Swann (Pad 37) • I had prepared the Non-Usage notices for 2010 with invitations to the August BOD meeting per the previously received instructions. Because they are going out so late, I included usage from 1 Jan 2010 through 31 May 2011 in the letter. None of the let- ters going out had any usage in 2011. Note that I dropped one person from the list because they had 4 uses from January through May 2011. These letters are now on hold per your instructions. • The reminders that the required pad usage is 4 times per year have been prepared for the people who only used their pads 3 times last. I am including their usage through May 0f 2011 in their letters so they know where they stand for this year as well. None of them have any usage yet in 2011. These are also on hold per your instructions. • After the offerings, we will have 4 pads available and 6 people on the waiting list. One pad is being added and there are 3 more that may be added bringing the number of open pads up to 5-8. With the possible revocations, we could have as many as 12 free pads. I plan to aggressively market the private pads (perhaps arrange a tour of available pads during the fall picnic?) and do another offering in the fall, probably starting just after the fall picnic. Outreach Committee Report. • Heise and KQ are scheduled • Starting to get calls for next year • High Tech High is interested in setting up an astronomy program – Michael Vander Vorst will follow up with them. Program Report. This month’s speaker will be Dr. William Welsh of the Kepler mission. NASA Robotic Observatory. • LX200 parts have not been sent out for repair yet – expect between $400 & $500 bill • Motion was passed to integrate CCD Commander to it (about $100), and replace the 3.3 reducer with a 6.3 reducer to reduce coma • $700 max approved to cover all of the above AISIG Report. AISIG meeting this month is on tips and tricks on image processing. Another hands-on session is being planned. Governing Documents Report. No report. Newsletter Report. Andrea is doing a great job. To help defray the increasing costs of printing and mailing, the newsletter page count needs to be cut back. The goal is 12 pages max, with emphasis on club news, events, and issues. The newsletter-only price will increase to $35; will continue to print to maintain the bulk mail rates – eventually the print version will go away. It may be cheaper to print the actual number of newsletters needed and send 1st class – Craig Ewing to investigate. Website Report. Creating a new AISIG website using Word Press; if it goes well, the SDAA site may be redone. The current AISIG page is in .ASP which has been hacked several times. Word Press is more secure. Site Master Plan Committee Report. Due to previously reported hardware failures, the back-ups are gone. Bill Carlson is recreating from an older version. November is the target date for submission to the county. Bill will prepare an article for the newsletter. Merchandise Report • Old merchandise will be sold at the same price as the new • No additional $$ for XL and up • Only made $40 at last week’s swap meet, low attendance (about 100) • $1,400 approved for restock of the merchandise – will use Merlin Embroidery. Plan to purchase hoodies, sort sleeve Ts, and hats and will sell as follows: o Hoodies - $30 o Ts - $15 o Hats - $15

SAN DIEGO ASTRONOMY ASSOCIATION NEWS AND NOTES, AUGUST 2011 Page 3 San Diego Astronomy Association

5. Old Business. • Audit Committee is good to go; Chuck Sten will do it. 6. New Business. • Reimburse $250 to Traweek for observatory floor paint – approved • Approve $250 max for observatory chairs • Approve $250 max for a weed wacker plus goggles, gas, oil, etc. • Approve $3,000 for a storage container • Membership and private pad fees will increase to cover ever-increasing cost of operations. $60 Contributing, $35 Basic, $60 pads. $5 Family remains as it was. Effective 1 Nov 2011. • $1,000 permit fee in budget and previously approved. • Brochures – we need more. Kin will research printers for the best price color, glossy, double-sided folded brochures. Will also look into business cards. Scott can create the artwork. • We need another repeater and pole for TDS internet (3rd node). Bill Carlson will lead this effort. $250 max was approved for the hardware. 7. Adjournment. Meeting adjourned at 8:58 pm.

Julian StarFest (JSF) 2011

Julian StarFest (JSF) 2011 will be held August 25th through the 28th on the grounds of Menghini Winery in Julian, CA. There are many activities planned, including a drawing for door prizes, and a public star party on Saturday the 27th. Check the www.julianstarfest. com website often to get up to minute information. activities.

SDAA members interested in volunteering for the Saturday night public star party, please contact Kin Searcy at [email protected].

SUMMER IN THE CITY

With the Summer Triangle high in the sky and the Scorpion crossing the meridian, it’s the season of tee shirt and shorts astronomy. Compared with last month, the August sky contains more bright stars (four stars of mag 1 or greater) and brighter , including Lyra (the Lyre) overhead, Cygnus (the Swan) and Aquila (the Eagle) high in the east, and Scorpius (the Scorpion) on the southern horizon. Vega (α Lyrae; magnitude 0.03; 25 light years distant), the fifth brightest star in the sky, is a bit north of overhead in early August. Vega, along with Deneb (α Cygni; mag 0.76; 1500 ly) about 30 degrees to the northeast, and Altair (α Aquilae; mag 0.73; 17 ly – home to Altair 4, the “Forbidden Planet”) about 30 degrees to the southeast comprise the Summer Triangle. When you look at Vega, it’s clearly brighter than Deneb (the 19th brightest star in the sky). However, the difference in their distances from us should give you pause. Typically, the brightness of a star is described in terms of its visual magnitude, i.e., how bright it appears to us from earth, with lower numbers indicating brighter. But another informative way to describe a star is by its “absolute magnitude”, which is a measure of the brightness of the star at a “standard” distance from earth – 10 (about 32.6 light years). Deneb has an absolute magnitude of -7.5, Vega has an absolute magnitude of 0.5, and Altair has an absolute magnitude of 2.3 (our Sun has an abs mag 4.8). At abs mag -7.5, Deneb is one of the brightest stars in our and, if in Vega’s position, would be visible to us during the day and would cast shadows at night. In the south, just past the meridian, heading west is Antares (α Scorpii; mag 1.0; abs mag -4.7; 550 ly), the heart of the Scorpion. Antares is a red supergiant and, with a radius of about 3 AU (1 AU = the distance of the earth to the sun), among the largest stars in our galaxy. If Antares was in the position of our sun, it would extend past Mars to the asteroid belt. About 30 million of our suns would fit inside Antares; for comparison, about 1 million earths would fit in our sun. Stars also are described by their “luminosity”, which is a measure of energy output, and is a function of a star’s temperature (to the fourth power) and its size (surface area). Luminosity differs, in part, from absolute magnitude in that the latter only considers visible light,

Page 4 SAN DIEGO ASTRONOMY ASSOCIATION NEWS AND NOTES, AUGUST 2011 San Diego Astronomy Association whereas luminosity includes energy from all parts of the electromagnetic spectrum, including X-ray, ultraviolet, and infrared radiation. Blue stars, which are the hottest stars, are more luminous than red stars of the same size, and blue supergiants like Deneb (and Rigel; α Orionis; abs mag -8.1), are among the most luminous stars. However, red supergiants like Antares (and Betelgeuse; β Orionis; abs mag -7.2) also are very luminous because of their large size; a significant amount of the energy of red giants is emitted as infrared radiation. Antares’ visible luminosity (abs mag) is about 10,000x greater than our sun, whereas its total luminosity is about 65,000x greater than our sun. Vega is the brightest star in Lyra and marks the head of the lyre, with a parallelogram of four stars forming the body. Through my 10 x 50 binoculars (6.5 degree fov), Vega forms a roughly equilateral triangle with a wider double star about 2 degrees to the northeast (epsilon (ε) LYR) and a closer double star about 2 degrees to the southeast (zeta (ζ) LYR). ε LYR is the famed “double double” (ε 1/2 LYR; 210 arcsec); through a telescope, each of the stars of the binocular double resolves into a double star. The stars of ε1 LYR (mags 5.0 and 6.0), the northernmost double, are separated by about 2.1 arcsec, and the stars of ε2 LYR (mags 5.3 and 5.4) are separated by about 2.4 arcsec. In my 12.5 inch reflector, the stars of the double double resolve at about 90x magnification; a dimmer star also appears in the field forming a nice triangle with ε1/2 LYR. Zeta LYR (44 arcsec; mags 4.3 and 5.6) anchors the northeast point of the parallelogram. The northwestern star of the parallelogram, delta (δ) LYR (630 arcsec; mags 4.5 and 5.6) is a nice binocular double star, with a blue component and a yellow component. Because of the similarity to Alberio (see below), I refer to this type of double star as an “alberioid”. The southeastern star of the parallelogram, β LYR is a four star system, with the brightest component an eclipsing binary star (mag 3.3-4.3), and three surrounding components (46, 67 and 86 arcsecs; mags 6.7, 9.9 and 9.9, respectively). The southwestern star of the parallelogram is gamma (γ) LYR. The Ring (M57) is a planetary nebula positioned about midway between β LYR and γ LYR (the southern stars of the parallelo- gram). The looks like a giant smoke ring, and is readily visible through my reflector in town. However, the central star of the Ring Nebula only shines at about mag 15, which is beyond the limit of most amateur telescopes. East of Lyra lies Cygnus, the Swan. Cygnus looks like a giant cross (with its base to the south). Deneb (α CYG) is the tail of the swan (“deneb” means “the tail”), Alberio (β CYG) is at the head, γ CYG is in the center, δ CYG comprises the first joint of the westernmost wing, and ε CYG forms the first joint of the easternmost wing. Cygnus lies in the northern part of the Milky Way, as is readily evident by the star studded field when scanning with binoculars from Deneb to Alberio. Alberio (35 arcsec; mags 3.4 and 4.7) is one of the most striking double stars in the sky because of the brightness of the primary and secondary stars and because of the brilliant gold and blue colors of the stars. A consensus in San Diego refers to the components as the “Charger” stars, but I like to think of them as the blue and gold eyes of the “mosaic” Swan. δ CYG (2.5 arcsec; mags 2.9 and 6.3) is a nice double star, with a secondary much dimmer than the primary. If I place Deneb to the east in my 10 x 50 binocular field, to the west of the field is another alberioid, omicron (ο) CYG, which actually is a triple star (106 and 331 arcsecs; 3.8, 7.0 and 4.8). The blue and gold components are readily evident through binoculars. If I place Al- berio to the north of my binocular field and look to the south, then move about 1-2 degrees further south and a bit east, the upside down “Coat Hanger” asterism comes into view, a nice grouping of stars containing about 15-20 fairly bright stars. To the south, Antares lies close to the ecliptic, which is the path the sun appears to take in the sky and along which the planets are observed. As such, at various times Antares appears in proximity to the planets, including Mars, as they orbit the sun. Because its color is similar to that of Mars, it was named “Ant-Ares”, which means “like Mars” (“Ares” being the Greek name for the Roman god, Mars) and is often translated as “rival of Mars”. Antares (2.5 arcsec; mags 1.0 and 5.4) is a challenging double star because the primary is so bright, and is much brighter than the secondary. The reward of splitting them is seeing the secondary, which is a rare “green” star. But is the secondary a green star, and, while you think about it, where are all the green stars? Well, and this is a simplified description, the absence of green stars appears to be due to the way our eyes see color. Cone cells in the eye individually see red, green, or blue and, in combination, produce our color vision; rod cells, which provide night vision, act primarily under low light conditions and have little if any role in color vision. In the electromagnetic spectrum, red has a longer wavelength, blue has a shorter wavelength, and green has a wavelength between red and blue. However, the individual red, green and blue spectra are not discrete, but overlap. A star’s color is dependent primarily on its temperature – cooler stars emit more light at longer wavelengths, including red, thus activating more red cone cells and look redder, while hotter stars emit more short wavelength light, including blue, and so activate more blue cone cells and look bluer. Stars with “middling” temperatures emit blue, green and red light and, because the spectra of blue, green, and red overlap, activation of green cone cells never dominates, and so we don’t see green stars; instead they appear white (like when you heat a piece of metal with a blow torch and it changes from red to white to blue as it gets hotter – no green).

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And what about Antares’ companion, because I’ve seen the green color? Well, one argument has been made that the green color is a “contrast” effect caused by Antares’ brightness making the otherwise light blue companion appear green. A second argument has been made that bright Antares saturates the cone cells so that only the rod cells see the companion (maybe like the Orion nebula, which we see with rod cells, can look greenish?). A third argument is the companion is a blue star and that the yellow light component of Antares com- bines with the blue color of the companion, to produce an apparent green color. What do you think? Scorpius has one of my favorite multiple star systems, Nu (ν) SCO (48 arcsec), which is another “double double”. To find ν SCO, locate the three bright stars that comprise the head of the Scorpion; the northeastern-most of these three stars is β SCO. Nu SCO lies about 2 degrees east of β SCO (note: don’t mistake omega (ω) SCO, which is a double star about 2 degrees south of β SCO). ν1 SCO (1.3 arcsec; mags 4.4 and 5.3) is a very close double and you may not recognize it as such at first, but you should be able to resolve ν2 SCO (2.4 arcsec; mags 5.5 and 7.2), which lies south of the brighter ν1 SCO. I can begin to resolve ν1 SCO at about 200x in my reflector, a task I find it easier using an aperture cover. An aperture cover is a cover placed over the front of an 8” or larger reflector telescope, with a hole cut out of one quadrant of the cover so that light only enters about 1/4 of the tube (between two spider veins). An aperture cover increases the effective F ratio of the telescope. While reasonable minds may differ as to the value of an aperture cover, I find that it sharpens the view, perhaps by accounting for less than optimal collimating and/or less than optimal optics, and in some cases maybe just by cutting down the amount of light. M4 (mag 5.4) is a globular cluster about 1-2 degrees west of Antares. Through binoculars, M4 is just visible at the western point of a squat triangle with Antares and sigma (σ) SCO, which is the next bright star northwest of Antares in the body of the scorpion. At 7000 ly distant, M4 is believed to be the closest globular cluster to us. A white dwarf, a pulsar (neutron star), and planet orbit one another in M4. Finally, in Scorpius, follow the stars of the scorpion’s body south of Antares to zeta (ζ) SCO, the last bright star before the body hooks east. NGC 6231 is an that lies just north of and includes ζ SCO. I’ve heard this cluster referred to as the “northern jewel box” cluster (the “southern” jewel box lies in Crux, the southern cross), and it really sparkles, even through binoculars, on a clear night if you have a good view low to the south. We can’t leave this month without mentioning Scutum (the Shield) and the , (M11; mag 5.8). M11 is a dense open cluster that is about 5000 ly from earth and may contain as many as 3000 stars that formed about 250 million years ago. To star-hop to M11, use the stars comprising the southern wing of Aquila, the Eagle. Start with Altair (α AQL), the southeastern-most star of the Summer Triangle, then look southwest to the first bright star, δ AQL, and continue to the next bright star, λ AQL. When you locate λ AQL, turn your binoculars to it and you’ll see a line of stars curving southwest; follow this path and you’ll come to M11, which looks like the stan- dard “hazy snowball”. Through a telescope, M11 resolves into a large number of stars in a fan shaped pattern. Many viewers consider the cluster a flock of ducks, whereas others consider it’s just one wild duck, with a mag 8 star for its heart and its mag 8 eyes looking toward the southwest. Before leaving Scutum, check out the general region around M11 with binoculars. This region comprises the Scutum star cloud, a rela- tively dust-free region of the Milky Way that allows a view into a spiral arm of the galaxy. You’ll see quite a few stars, even under city lights; at a dark sky site, it always draws my attention. Part 2 – THE ARCHER I was going to end this month’s article with Scutum, but now Sagittarius is up and waiting until September to discuss it didn’t make sense. The sky keeps moving, and I’m trying to catch up; so, instead of September, we’ll have a “Part 2” this month…bear with me. I get it, under a dark sky, why Sagittarius is referred to as the “teapot”, the Milky Way steaming from its “spout”, and its little northern lid and eastern handle, but in the city and in history, Sagittarius is the Archer, the tip of his Robin Hood cap to the north, his elbow pulled back to the east, drawing his bow to the west and raising his arrow in aim at the heart of the Scorpion ever scurrying to escape into the west; one of the great celestial action scenes. The Scorpion’s stinger directs the way to Sagittarius and the center of the Milky Way. The two bright “stinger stars”, at the tip of the Scorpion’s tail, easternmost lambda (λ) SCO (Shaula; mag 1.6) and westernmost upsilon (υ) SCO (Lesath; mag 2.6) point to the open cluster, M7 (mag 3.3), about 6 degrees east and a bit north. Referred to as Ptolemy’s cluster (after the astronomer, not Cleopatra’s family), M7 con- tains about 200 stars and is about 1000 ly away. Even in the city, on dark nights, I can see a glow in the region of M7; through binoculars it’s a great site, and viewing M7 in my tripod mounted 20 x 60 binoculars (2.3 fov), which frame it beautifully, or at about 60x in my reflector, I’m reminded why it’s one of my favorite open clusters. About 5 degrees north/northwest of M7 lies the smaller, dimmer open cluster, M6 (mag 4.2), the Butterfly cluster, the stars of which form the shape of a butterfly when viewed through my reflector at about 60x (not so much through binoculars). The Butterfly cluster is about 2000 ly away and contains mostly young blue stars and one bright orange star (at the tip of a wing).

Page 6 SAN DIEGO ASTRONOMY ASSOCIATION NEWS AND NOTES, AUGUST 2011 San Diego Astronomy Association

This is another good time for pulling up a chair and sweeping with binoculars along a line starting at the stinger stars, through M6, and into Sagittarius, and just take in the open and closed star clusters and nebulae and star clouds. On a clear, moonless night in the city you can just follow the densest star path northward through the Milky Way to the Scutum Star Cloud and on into Cygnus; at a dark sky site it’s a wondrous view. Once you have your general bearings, hit some of the highlights. You’re in the region of the galactic center, which is globular cluster central, with 14 Messier globular clusters in the region bounded by Scorpius, Sagittarius, and Ophiuchus to the north. So let’s find one. Start at λ Sagittarii (SGR), which is the star at the tip of the Archer’s hat (the teapot’s lid). If I put λ SGR to the west of my binocular field, about 2.5 degrees to the east is another hazy snowball, the globular cluster, M22 (mag 5.2; brighter than M13, mag 5.3), located about 10,000 ly from here. M22 is the best globular cluster in this region, and a favorite of many. Through my reflector, M22 is a compact cluster that resolves into a couple of dozen stars at 90x; a little right triangle formed by 7 stars sits just to its north. M22 is one of only four globular clusters (including M15, in Pegasus) to contain a planetary nebula (GJJC1). Unfortunately, GJJC1 is a mag 15 object (same as the central star of M57), so you’ll need a large telescope and dark skies to see it. About 6-7 degrees northwest of λ SGR lies the , M8 (mag 6.0; 4000-6000 ly). On a clear, dark night, M8 shows up as a cloudy, star-rich region through binoculars. Like the Orion Nebula, the Lagoon Nebula is a star-forming region. Through a telescope, a large number of young stars are visible in the nebula (open cluster NGC 6530). De- pending on the sky, you may only see some nebulosity around the stars at the western end of the cluster. An OIII filter, which passes only the pair of emission lines of oxygen, can improve the view of the nebula. Just north of the La- goon Nebula lies the (M20; mag 9.0), though it doesn’t show well, if at all, under city lights. This region of the sky coincides with the galactic center (estimated at RA 17hr45min40sec; dec -29 degrees). The galactic center lies about 25,000 ly away and is believed to contain a supermassive black hole of about 3.5 million solar masses. Associated with this region is an intense radio source, Sagittarius A* (A star), which is believed to correspond to the accretion disc surrounding the black hole. More than 100 young, large, hot stars are pres- ent in the immediate region of the black hole; it’s not presently known how new stars can form in a region of such high tidal forces. About 7 degrees north/northwest of λ SGR, the northern tip of the Archer’s bow, is the multiple star mu (μ) SGR (15.8, 25.6, 48.7 and 50 arcsecs; mags 3.4-3.9, 10.5, 13.5, 10.0 and 9.4). I can’t see the mag 13.5 component, but the rest of the system provides a nice view with the two most distant companions on opposite sides of the eclipsing binary primary and the closest companion perpendicular to them on one side of the primary. About 2-3 degrees northeast of μ SGR lies M24, the Small Sagittarius Star Cloud (mag 2.2). Like the Scutum Star Cloud, M24 is a relatively dust-free region of the Milky Way that allows a clear view along the galactic disk. North of M24 are two more nebula, M17 (the Swan Nebula; aka the ; mag 7.0) and M16 (the ; mag 6.0), famous for the Hubble “Pillars of Creation” image. Neither shows up very well in the city, though you can improve the view with an OIII filter. The Eagle Nebula is in the Serpens Cauda, which is connected to Serpens Caput (discussed last month) through Ophiuchus (the Serpent Bearer). Ophiuchus lies north of Scorpius and Sagittarius, and has a roughly ovoid hexagonal shape with fairly bright stars along its perimeter, several seemingly in pairs, and few visible stars in its interior. The globular clusters M10 (mag 6.6) and M12 (mag 6.8) are about 5 degrees east of the two westernmost perimeter stars, δ and ε Ophiuchi; try scanning the region for them on a dark night. Serpens Cauda comprises a dim line of stars that begins at the southeastern end of Ophiuchus and rises to the northeast, ending between the wings of Aquila. Although M16 is within the boundaries of Serpens Cauda, it’s easier to find by starting in Sagittarius, as discussed above. We’ll end with Delphinus (the Dolphin), a bright little constellation splashing about 15 degrees northeast of Altair. Delphinus contains five stars of mag 3.7 to 5.2, making it readily visible on most nights, especially since it’s in a relatively sparse region of the sky. Gamma Delphini, at the tip of the Dolphin’s nose, is a fine double star (9 arcsec; mags 4.5 and 5.0), with gold and blue components. About 1 degree south of γ DEL lies Struve (Σ) 2725, the “Ghost Double” (mags 7.5 and 8.2; 6 arcseconds); these double stars fit in the same field in my reflector at 200x. Two more things: 1) Happy Birthday to Neptune! It’s been one Neptunian year since the little blue planet was identified. 2) It was February 2009, but seems like only yesterday, that Dr. Marc Rayman of JPL was edifying us at the annual banquet about the Dawn Mission to Vesta and Ceres, and now (July) Dawn is entering orbit around Vesta. Check out August 2011 Sky and Telescope for a chart and find Vesta in Capricornus. Erratum: In last month’s article, it mistakenly was said that “Serpens Cauda contains globular cluster M5”. However, M5 is in Serpens Caput. © 2011 – San Diego Stargazer SAN DIEGO ASTRONOMY ASSOCIATION NEWS AND NOTES, AUGUST 2011 Page 7 San Diego Astronomy Association

SDAA Contacts Club Officers and Directors President Michael Vander Vorst [email protected] (858) 755-5846 Vice-President Bill Carlson [email protected] (425) 736-8485 Recording Secretary Brian McFarland [email protected] (619) 462-4483 Treasurer Ed Rumsey [email protected] (858) 722-3846 Corresponding Secretary Jeff Herman [email protected] (619) 846-4898 Director Alpha Bob Austin [email protected] (760) 787-1174 Director Beta Scott Baker [email protected] (858) 442-7513 Director Gamma Michael Finch [email protected] (760) 440-9650 Director Delta Kin Searcy [email protected] (858) 586-0974

Committees Site Maintenance Bill Quackenbush [email protected] (858) 395-1007 Observatory Director Jim Traweek [email protected] (619) 207-7542 Private Pads Mark Smith [email protected] (858) 484-0540 Outreach Kin Searcy [email protected] (858) 586-0974 N. County Star Parties Doug McFarland [email protected] (760) 583-5436 S. County Star Parties -Vacant- [email protected] E. County Star Parties -Vacant- [email protected] Central County Star Parties Kin Searcy [email protected] (858) 586-0974 Camp with the Stars Doug McFarland [email protected] (760) 583-5436 K.Q. Ranch Coordinator Bill Griffith (760) 525-9954 Newsletter Andrea Kuhl [email protected] (858) 547-9887 Membership Ed Rumsey [email protected] (858) 722-3846 New Member Mentor Jerry Hilburn (858) 565-4059 Webmaster Bob Austin [email protected] (760) 787-1174 AISIG Kin Searcy [email protected] (858) 586-0974 Site Acquisition Jerry Hilburn [email protected] (858) 565-4059 Field Trips Bill Carlson [email protected] (425) 736-8485 Grants/Fund Raising Jerry Hilburn [email protected] (858) 565-4059 Merchandising Paul “Moose” Pountney [email protected] (619) 465-7014 Publicity Jerry Hilburn [email protected] (858) 565-4059 Roboscope Director Jerry Hilburn [email protected] (858) 565-4059 Governing Documents Scott Baker [email protected] (858) 442-7513 TDS Network Bill Carlson [email protected] (425) 736-8485 Amateur Telescope Making Peter De Baan [email protected] (760) 745-0925

Have a great new piece of gear? Read an astronomy-related book that you think SDAA Editorial Staff others should know about? How about a photograph of an SDAA Member in Editor - Andrea Kuhl action? Or are you simply tired of seeing these Boxes in the Newsletter rather [email protected] than something, well, interesting? Assistant Editor: Rick Imbra Contributing Writers Join the campaign to rid the Newsletter of little boxes by sharing them with the John Mood membership. In return for your efforts, you will get your very own by line or pho- Michael Vander Vorst tograph credit in addition to the undying gratitude of the Newsletter Editor. Just send your article or picture to [email protected].

Page 8 SAN DIEGO ASTRONOMY ASSOCIATION NEWS AND NOTES, AUGUST 2011 San Diego Astronomy Association

August 2011

Sunday Monday Tuesday Wednesday Thursday Friday Saturday 1 2 3 4 5 6 Wm Heise Camp with the Stars Stars in the Park

7 8 9 10 11 12 13

SDAA Business Stars at Mission Meeting Trails Full Moon

14 15 16 17 18 19 20 TDS Public Night SDAA Program Meeting KQ Ranch

21 22 23 24 25 26 27

AISIG Meeting Julian StarFest Julian StarFest Julian StarFest SPIE Convention

28 29 30 31

Julian StarFest New Moon

SAN DIEGO ASTRONOMY ASSOCIATION NEWS AND NOTES, AUGUST 2011 Page 9

San Diego Astronomy Association

AISIG Gallery

Bob Austin and Peter Morrison combined imaging data to produce this fine image of the (NGC 6888) in Cygnus. Readers of the newsletter in black and white should view this on the AISIG gallery (http://aisig.sdaa.org) to see the color. There are over 12 hours of data included in the processed image.

Page 10 SAN DIEGO ASTRONOMY ASSOCIATION NEWS AND NOTES, AUGUST 2011 San Diego Astronomy Association

Jim Thommes posted some great galaxy images. The single galaxy is The Fireworks Galaxy (NGC 6946) on the border between Cepheus and Cygnus and the dual are NGC 5965 and NGC 5963 in . These images were made with an SBIG ST8300M CCD camera on a Celestron C8 mounted on a Losmandy G11 mount.

SAN DIEGO ASTRONOMY ASSOCIATION NEWS AND NOTES, AUGUST 2011 Page 11 San Diego Astronomy Association P.O. Box 23215 NON-PROFIT ORG. San Diego, CA 92193-3215 U.S. POSTAGE (619) 645-8940 PAID VOL XLIX Issue 8, August 2011 PERMIT NO. 3489 Published Monthly by the San Diego Astronomy Association SAN DIEGO, CA. Subscription $30.00/year, Single Issue $2.50

THE BACK PAGE

Total Solar Eclipse Nov 14, 2012 Australia Two members and spouses of SDAA have signed up for the cruise to totality from Hawaii to Australia on Celebrity Millennium. While it seems a long way away, make plans early to meet the moons’ shadow. The cruise is 20 days, Nov 2-20, 2012, departing Hawaii and sailing across the equator with ports of call in Samoa, Fiji, New Zealand, ending in Sydney after viewing the eclipse at sea Nov 14. Pricing is quite good, the ship is repositioning from the northern to southern hemisphere. If you cannot take 20 days, you can get on or off at intervening ports. While there are many eclipse tours, we had a great cruise to totality in Libya 2006 with TravelQuest. We didn’t find out until after we returned there were other SDAA members onboard, so if you are interested, check out the TravelQuest web site and send us an email at [email protected]. Here is a YouTube video I took during totality in Hungary: http://www.youtube.com/watch?v=Rp4zEA_EjQQ For sale: I am helping a friend to sell his astrograph telescope. I have it at my home in San Diego. It is a 10" f/3 Baker-Schmidt design astro- graph. Comes with a 4" by 5" photographic plate holder, Losmandy dovetail plate. Gives a full 90mm circular disc image. Wooden case. All in good working condition, you are welcome to see it. Asking price $3000.00 Pictures upon request. Alberto Levy 858-414- 5416 [email protected] Losmandy GM-8 with GOTO system. Includes, leg clamp lever set,clutch knob set, two weights 7 and 11lb.,accessory tray and polar scope finder. $1800.00 like new hardly used. Contact: Wayne Rose at 619-459-0305 MEMBERSHIP INFORMATION Send dues and renewals to P.O. Box 23215, San Diego, CA 92193-3215. Include any renewal cards from Sky & Telescope, Astronomy, or Odyssey magazine in which you wish to continue your subscription. The expiration date shown on your newsletter’s mailing label is the only notice that your membership in SDAA will expire. Dues are $50 for Contributing Memberships; $30 for Basic Membership; $50.00 for Private Pads; $5 for each Family membership. In addition to the club dues the annual rates for magazines available at the club discount are: Sky & Telescope $32.95, Astronomy $34, Sky Watch $6.99, and Odyssey $25.46. Make checks payable to S.D. Astronomy Assn. PLEASE DO NOT send renewals directly to Sky Publishing. They return them to us for processing.