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The Monochrome Print Version December 2010 onomica tr l A s s A s e o s c i o a J t i EPHEMERIS o n a n S SJAA 1980 occultation observation of a SJAA Activities Calendar satellite of asteroid (216) Jim Van Nuland Gene A. Lucas November (late) detector. Holiday Party follows. Observations of a satellite of asteroid 21 Fall Swap. Open at noon, selling See page 5. (216) Kleopatra made 30 years ago by 1:00 to about 4:00 p.m. In the SJAA members, Gerry Rattley and Bill hall at Houge Park. January Cooke, have now been substantiated 26 Astronomy Class at Houge Park. 1 Dark-Sky weekend. Sunset 5:01 professionally. 7:30 p.m. Topic is “What You p.m, 5% moon rises 5:59 a.m. Can See In The Sky - Part 2”. 8 Dark-Sky weekend. Sunset 5:07 At the recent American Astronomical 26 Houge Park star party. Sunset p.m, 21% moon sets 9:38 p.m. Society meeting in Pasadena on October 6, 2010, a presentation was made by 4:52 p.m., 68% moon rises 10:04 Henry Coe Park’s “Astronomy” lot has Dr. Franck Marchis (SETI Institute, UC- p.m. Star party hours: 7:00 until been reserved. Berkeley) on “Characteristics of Known 14 Houge Park star party. Sunset 5:13 10:00. Triple Asteroids in the Main Belt”. One p.m, 75% moon sets 3:28 a.m. Star 27 Dark Sky weekend. Sunset 4:51 point made during Dr. Marchis’ AAS talk p.m., 57% moon rises 11:13 p.m. party hours: 7:00 until 10:00 p.m. was that the visual observations made by 15 General Meeting. Our speaker Gerry Rattley and Bill Cooke during the December is TBD. Board meeting at 6:30; October 10, 1980 stellar occultation by 4 Dark Sky weekend. Sunset 4:50 General Meeting at 8:00 (216) Kleopatra (near Loma Prieta, CA; p.m., no moon. Henry Coe 28 Astronomy Class at Houge Park. reported to IOTA), were now deemed Park’s “Astronomy” lot has been 7:00 p.m. The topic: TBA. not only plausible, but very probable. The reserved. 28 Houge Park star party. Sunset 5:22 results for (216) Kleopatra were included 10 Astronomy Class at Houge Park. p.m, 23% moon rises 3:53 a.m. Star with further results for five other asteroids 7:30 p.m. Topic is TBD. party hours: 7:00 until 10:00 p.m. that show duplicity and/or satellites. 10 Houge Park star party. Sunset 29 Dark-Sky weekend. Sunset 5:29 4:50 p.m., 29% moon sets 9:56 p.m, 15% moon rises 4:46 a.m. (216) Kleopatra is a relatively large asteroid, measuring 217 × 94 × 81 km. It is believed p.m. Star party hours: 7:00 until to be a loosely packed metallic object, 10:00. based on its radar albedo. Kleopatra is 18 General Meeting at 8 p.m. Our 217 km (135 miles) long, give or take The Board of Directors meets speaker is Dr. Tim Dubbs, speak- 25% — about the size of the state of New before each general meeting at ing on Particle Physics and on Jersey. The irregular, bi-lobate (“dumbbell’) 6:30 p.m. All are welcome to his work on the LHC’s particle elongated shape has been strongly attend. confirmed by teams of IOTA occultation observers on several occasions (1980, 1991, 24 hour news and information hotline: 2008, and 2009). (408) 559-1221 http://www.sjaa.net Continued on page 2 Copyright © 2010 San Jose Astronomical Association, Inc. Volume 21 Number 12 Official publication of the San Jose Astronomical Association, December 2010 1980 occultation observation of a satel- lite of asteroid (216) by the professionals — For many edu/~fmarchis/Science/Asteroids/ Continued from page 1 years, the thought of the existence of Triple/DPS2010/DPS2010_Marchis.pdf satellites of asteroids was held to be And an abstract for their forthcoming In 2008, Marchis’ team imaged (216) implausible, if not impossible — just paper, submitted for publication in Kleopatra with the Keck II telescope as the concept of irregular shapes for the professional journal ICARUS, adaptive optics, definitely showing the the asteroids was also held in contempt is here:http://adsabs.harvard.edu/ irregular “peanut” shape of the asteroid, by many theoreticians previously. Of abs/2010DPS....42.4605M along with two nearby satellites. Other course, direct images from spacecraft researchers have previously imaged have confirmed what was previously Kleopatra with the large radar dishes at suggested by many ground-based Goldstone and Arecibo, producing a 3-D occultation observations. (This is also Gerry Rattley served as an SJAA officer map of its shape and orientation. Now, true for several of the comet nuclei and Board Member during the 1980s, Marchis and his team have plotted the which have been imaged, including and was a recipient of the A.B Gregory orbits for two satellites of the asteroid, recent radar results for Comet 103P Award in 1982. He has continued to which strongly confirms likelihood of Hartley.) be an active occultation observer the visual occultation observations of a and member of the International satellite by Rattley and Cooke, made in The details of the story are explained Occultation Timing Association (IOTA). October, 1980. in an article published on the internet Since moving to Gilbert, Arizona in by Kelly Beatty, a columnist for Sky July, 1982, Gerry has been active in the This marks a distinct turning point — and Telescope magazine, who was Saguaro Astronomy Club and more for now, 30 years later, professionals in the audience at the October AAS recently, the East Valley Astronomy have at last recognized the value of meeting in Pasadena: http://www. Club. Presently he is an active volunteer such occultation observations by skyandtelescope.com/news/104690129. telescope operator at the Gilbert Rotary amateurs. For since that time, those html. The complete PPT presentation Centennial Observatory (GRCO) in observations have been either largely by Dr. Marchis and his team may be Gilbert, AZ. ignored, or denigrated completely downloaded here: http://astro.berkeley. The Shallow Sky Full of Moon Akkana Peck Although there are plenty of planets usual, the moon is offset within the Prior to LOLA, the highest point on the to watch in December — Jupiter high Earth's shadow; the north limb of the moon was thought to be Beta in the in the sky, Uranus and Neptune visible moon will be brighter than the south Leibnitz Range, at 36,000 feet. That one in the early evening, Mercury low in during totality. you *can* see, at least in months when the evening during the first half of the there's a good western libration so Mare month, and Venus and Saturn in the It's been a while since we've had an Orientale is tilted toward us. December morning — the real news this month is eclipse this good! But the eclipse isn't the isn't ideal but it isn't bad. On the 20th all about the moon. only moon news. Our satellite has been while you're waiting for the eclipse to in the science press quite a bit over the start, swing over to the southwestern We'll see (weather permitting) a past month. limb of the moon, get out your Rukl and spectacular lunar eclipse on the evening turn to chart 61 and libration chart VII. of Monday December 20th, perfectly For instance, the Lunar Orbiter Laser Rukl doesn't label the Leibnitzes, but placed with the moon way up at 75 Altimeter (LOLA) team just announced they're near Valles Bouvard, just outside degrees. The moon will be just above that they'd found the highest point the southern edge of the Cordillera the raised arm of Orion, as though the on the moon. Unfortunately, you mountains. full moon were a tennis ball Orion is can't see it: it's on the lunar far side, a about to lob right through the Hyades. visually undistinguished gentle rise near Okay, so the Engel'gardt area isn't the Engel'gardt on the fringe of the Korolev most impressive lofty peak you've seen. The penumbral eclipse begins at 9:29pm plain. It's 10,786 meters (35,387 feet) But there was other moon news last PST. This stage is very subtle and you above the lunar datum — an arbitrary month. probably won't see any difference, but it point chosen to act as "sea level" on the doesn't hurt to try! Partial eclipse begins moon. For comparison, Everest is 8,848 "Water on the moon!" screamed the at 10:32, with totality lasting from 11:40 meters above Earth's sea level. headlines. The results came from several p.m. until 12:53 Tuesday morning. As new papers analyzing the results of the SJAA EPHEMERIS Page 2 December 2010 LCROSS impact. Remember LCROSS? the big bare spot in the mountainside month, so you'd need somewhere It crashed into Cabeus crater near the that you can't help but notice when you around 65 tons of rock, 650 cubic feet moon's south pole in October 2009, and fly out of San Jose? 12 gallons doesn't or about 24 cubic yards, or a cube about we were all disappointed that it didn't sound like very much compared to the 8.6 feet on a side. produce a big visual plume. But it did needs of a working lunar base. produce lots of spectral data, which has Okay, that isn't that big a slag pile after finally been processed and published — But how much rock is a ton of rock? all.
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