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Journal of the Amateur Astronomers Association of New York September 2007 Volume 55 Number 9, ISSN 0146-7662

EYEPIECE

Astronomy Enters the New World of iPods and Podcasts
By Edward J. Fox
"Pods" have always been a part of space jargon and space lore. There were the infamous "pods" of "The Invasion of the Body Snatchers." Then there was this exchange in Arthur C. Clarke's classic "2001 ­ A Space Odyssey":
DAVE: "Open the Pod Bay Doors HAL..." HAL: "I'm sorry Dave, I'm afraid I can't do that..." DAVE: "My God...it's full of stars!" Today, pod is widely used in the vernacular: iPods and Podcasts. They can convey bountiful knowledge about astronomy and the universe. IPods are simply adjuncts to computers that are capable of playing a variety of computer files. First and foremost are music mp3 files, a format that digitally compresses a sound file. Compressing of the file allows a small computer accessory--an mp3 player--to store a number of these sound files and play them back. IPod is the brand name for the Apple version of the mp3 player. Podcasts can be of any type of program. Of interest to Ey epiece readers are a number of programs, documentaries and lectures dealing with astronomy. IPods and computers are capable of doing much more than playing sound recordings. They can record and play back various types of video podcasts (also referred to as videocast or vodcast). You can have a visual program about the latest discoveries about the universe on your desktop--or better yet, in the palm of your hand. Following are a number of astronomy-related podcasts and videocasts that can be downloaded from the Internet via http://www.apple.com/itunes/ download. Apple's iTunes software is a primary

"podcast catcher" or conduit for "subscribing" to podcasts so they're downloaded to your computer. These Podcasts can be played either on a computer or on an iPod or other mp3 player.
Almost all podcasts are free, even the ones "subscribed" to through iTunes and the iTunes Store. These Podcasts can be synchronized (synced) with your iPod or other mp3 player on a regular basis. That simply means they are downloaded to the player, as if it were a hard drive. Of course, to see the video programs, a video capable player, such as the iPod 30 or iPod 80, is required. For an explanation of how podcasts can be accessed, go to Prof. Richard Pogge's site at http:// www.astronomy.ohio-state.edu/~pogge/Ast161/Audio/. Most of these Podcasts are less than a year old, but they offer significant archives of past episodes that can be downloaded. They're excellent for the novice amateur astronomer to learn about the myriad of scientific terms and technologies. They're also useful to the seasoned astronomer to keep up with rapidly changing findings. Podcasts/Videocasts are described in the Medical/ Science section of the iTunes Podcast listings. Astronomy 161 and 162. P r esents the a udio of two full-semester courses given at Ohio State by Prof. Pogge. Astronomy 161 is an introduction to modern astronomy, with an emphasis on the solar system. Astronomy 162 is an overview of modern astrophysics beyond our solar system, picking up where Astronomy 161 leaves off. Each lecture is about 40 minutes. Course materials are available at the website. Astronomy Cast. See stor y on pa ge 4.

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What's Up
By Tony Hoffman The Sky for September 2007
Chi Cygni at Maximum. C h i C ygn i is a M ir a -type long-period variable star that every 13 months or so rises from obscurity to about magnitude 5 (a 10,000-fold increase in brightness) and then fades. In summer 2006, Chi Cygni became unusually bright, peaking at magnitude 3.7. It was an easy binocular target from the city, prominently placed along the neck of Cygnus the Swan and distinctively orange-red, and was even visible to the naked eye, particularly from the outer boroughs. Chi Cygni is due to reach maximum around September 22. Will it repeat last year's performance, or turn in a more typical showing, Vesta Meets Jupiter. Ast er oid 4 Vest a h a s fa d ed con siderably since its unusually bright opposition in late May, but it has one more surprise for us. From late August until October, it's in Ophiuchus, near Jupiter. The pair is closest on August 30, when Vesta passes less than half a degree from Jupiter, at magnitude 7.2 appearing somewhat fainter than Jupiter's Galilean moons. Vesta will then gradually pull away, lying about 5 degrees to the left of Jupiter in mid-September. Aurigid Storm? E a r ly-morning risers should keep an eye out for meteors the first morning of the month. Normally this shower, which radiates from near Capella, is sparse, but astronomers have predicted that this year Earth will encounter an unusually dense part of the dust trail of Comet Kiess, the shower's parent body. Unfortunately the peak, which could send hourly meteor counts into the tens or hundreds, is supposed to occur around 7 a.m., after the Sun has risen, but there may be increased activity in the hours before dawn. A bright gibbous Moon won't help the situation. Chi Cygni should be an easy binocular object when it reaches maximum around September 22. September 1 Aurigid meteor shower peaks. September 2 Asteroid Pallas 2 at opposition. September 3 Last-quarter Moon at 10:32 p. m.; Moon passes 1.2 degrees from Pleiades. September 4 Moon passes 6 degrees from Mars. September 8 Uranus at opposition; Moon lies near Saturn and Regulus. September 11 New Moon at 8:44 a.m. September 18 Moon lies near Antares. September 22 Mercury less than half a degree from Spica. . September 23 Autumnal equinox at 5:51 a.m.; Venus at greatest brilliancy, mag. -4.8. September 26 Full Moon at 3:45 p.m. September 27 Moon at perigee, 223,332 miles from Earth, 9:54 p.m. September 29 Mercury at greatest elongation in evening sky.

Major Disturbances in Jovian Belts Continue
By Joseph A. Fedrick
I continued to monitor Jupiter in July and August using my 60mm refractor at 50x and 100x, and my 150mm reflector at 150x. Jupiter was the only solar-system object other than the Sun and Moon to be in view at con2

venient hours as Venus and Saturn rapidly sank into the solar glare and out of view in the west during July. Mars rose earlier each morning but still rose well after midnight and appeared as a featureless coral-pink orb in my 60mm refractor at 50x and 100x. The Sun revealed two impressive groups of spots as seen from Rick Davis' reJovian belts continued on page 10


A Message from AAA President Richard Rosenberg
Hello, members: I've had a lot of fun this summer joining fellow AAA members at dark-sky locations in Columbia County and the Catskills. Thanks to Tom Haeberle and John Swierzbin for the work they've put in. I hope to make arrangements soon which will enable us to observe regularly at a location far from the city next summer. We've just had a meeting of our revitalized website committee. Nick Stroud, Ed Fox and Shana Tribiano joined webmaster and committee chair Marcelo Cabrera and me. Marcelo's employer, Tana Seybert, will generously host our site for free. We hope to update the look of the site, add advertising and streamline membership processing within the next few months. Check www.aaa.org to track the changes. Even better, e-mail phone me if you'd like to participate.

On September 8 from 8 p. m. to midnight, area astronomy clubs will gather at Custer Institute for a star party. Attending will be the Amateur Observers Society, the Astronomical Society of Long Island and Montauk Observatory, as well as the AAA. Custer is in Southold, on the north fork of Long Island. It 's a wonderfully dark site with a large clubhouse, an observatory with a 14-inch Celestron and a large area to set up scopes. All AAA members are invited.
Our annual Starfest gathering at the Central Park Sheep Meadow will be Saturday, November 10 from 6:30 to 10 p. m., with rain date the next evening. We're holding it a little late this year so we'll be able to see Mars at a convenient hour (it will be at opposition in December). Invite your friends and bring your scopes, binoculars and yourselves. Rich Rosenberg, AAA President, pr esident @a a a .or g, (718) 522-5014

Talk on the Hubble Will Begin AAA's '07-'08 Lecture Series
Dr. Mario Livio, senior astrophysicist and head of the Office of Public Outreach at the Space Telescope Science Institute (STScI), Baltimore, will open the AAA's 2007-08 lecture series when he discusses "Achievements of the Hubble Space Telescope" on Friday, October 5. The free public lecture is at 6:15 p. m. in the Kaufmann Auditorium of the American Museum of Natural History. Livio's talk will be the AAA's annual John Marshall Memorial Lecture. Marshall, who served as president and later as executive director of the club, is considered a seminal figure in the AAA's growth. He died in 1997. "In its 17 years of operation, the Hubble Space Telescope has had a profound effect on all areas of astronomical research," Livio says. "I will present my choice of Hubble's most riveting contributions, in topics ranging from the solar system and extrasolar planets, to galaxy formation and the nature of dark energy." The STScI conducts the Hubble's scientific program. Livio received his Ph.D. in theoretical astrophysics from Tel Aviv University, was a professor of physics at the Technion-Israel Institute of Technology and joined STScI in 1991. His interests span a broad range of topics in astrophysics, from cosmology to the emergence of intelligent life. Livio has done much fundamental work on the topic of accretion of mass onto black holes, neutron stars and white dwarfs, as well as on the formation of black holes and the possibility of extracting energy from them. During the past nine years, Livio's research has focused on supernova explosions and their use in cosmology to determine the rate of expansion of the universe, and the nature of the dark energy that causes cosmic expansion to accelerate. He's authored three popular science books: "The Accelerating Universe," "The Golden Ratio" and "The Equation that Couldn't Be Solved." Lectures continued on page 10
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Review: A Fact-Based Journey through the Cosmos
By Edward J. Fox
It's possible to take a journey through the cosmos at your computer, thanks to the podcast Astronomy Cast. Since September 2006, two people have "published" a free weekly podcast program about all aspects of the cosmos. They're Dr. Pamela Gay, visiting assistant professor of physics at Southern Illinois University, where she teaches physics and astronomy, and Frazer Crain, publisher of the website Universe Today. The team approaches each subject as a discussion, with Gay explaining the subject and Crain playing the role of foil or stand-in for the common man. Gay can explain complicated facts and theories in clear and understandable terms. If that's not enough, Crain, an expert in computer science and astronomy, can ask questions that lead the conversation and summarize using short, pithy word illustrations. Since the program is produced only in an audio format, it's left to the listener to interpret the word pictures to illustrate the subject. One example to explain the make -up of what we see in the universe was to think of the solar system and the planets as older people surrounded by rings of ever younger people. The further something is from us, we're seeing it as it was when it was younger, millions and billions of years ago. The website has at least one illustration for each program, but the audio podcasts don't include visuals. The program experimented with publication of visuals for several early shows, but the effort was abandoned due to limitations of the software and the limited production budget. Illustrations may be reinstituted. Podcasts continued from page 1 Astronomy Magazine Podcast. Astronomy ma ga zine's weekly discussions cover the latest space news, go deeper into magazine stories and preview sky events. NASA's Jet Propulsion Laboratory Video and Audio Podcasts. Ha s a la r ge a r chive tha t conta ins pa st P odcasts and Videocasts that shouldn't be overlooked.
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More than 45 podcasts have been produced. All past episodes can be downloaded and enjoyed when convenient--at home or, using mp3 technologies, in the car. There are also discussion forums and it's possible to download a transcript of each episode. Each broadcast is 35-40 minutes, with most limited to a single subject. A sampling of timely topics: Discovering Another Earth; The Search for Neutrinos; The Sun, Spots and All; Asteroids Make Bad Neighbors; String Theory, Time Travel, White Holes, Warp Speed, Multiple Dimensions and Before the Big Bang; What is the Universe Expanding Into?; The Fermi Paradox: Where are all the Aliens?; Choosing and Using a Telescope. One episode was titled "What We Learned from the American Astronomical Society." Gay had attended the annual AAS conference and interviewed astronomers who'd made presentations. As she said, it's difficult, even for the professional or advanced amateur astronomer, to stay current in the field. In addition to single-subject programs, Astronomy Cast periodically devotes a program to questions that have been sent to the site by listeners, either e-mails or voice messages. Questions that are answered are preselected, so answers are preplanned and well thought out. Episodes can be downloaded individually or subscribed to at no cost through a variety of "podcast catcher" software, including iTunes. The show can be found at www.astronomycast.com.

NASAcast Video. The la test video fea tur es fr om www.NASA.gov, NASATV and more. Hidden World of the Spitzer Telescope. This ser ies showcases discoveries in infrared astronomy. Hubblecast. The la test news a bout a str onomy, spa ce and the Hubble Space Telescope. Episode 1 was first produced on February 28.


What You Need to Know on Choosing and Using Binoculars
By Julian Parks
Most amateur astronomers just starting out want to get a telescope, but instead should get a pair of binoculars. Binoculars are cheaper and of better value than a small telescope. Binoculars can be used as an accessory to a telescope to help find a deep-sky object or an asteroid, to learn the constellations, to follow sunspots, to follow the Moon and planets among the constellations, and to observe sky conditions, comets, variable stars and novae. Never look at the Sun with binoculars. It will permanently blind you. Always use proper solar filters. Always wear the neck strap so you don't drop your binoculars. Age is the single most important factor in choosing a pair of binoculars. As we age, our exit pupils or the size of our pupils under low-light conditions tends to get smaller. By age 50, our exit pupils may be 5mm. When younger, the exit pupil can be 7mm to 8mm. Therefore, you have to match your exit pupil to the exit pupil of the binoculars you're buying. To determine the exit pupil of a pair of 7x50 binoculars, divide the aperture, 50mm, by the magnification, 7x, and get 7.1mm. Under city conditions, even if you have a 7mm exit pupil, your pupils will never fully dilate to 7mm. This usually means a 10x50 binocular with a 5mm exit pupil is the choice for city observers. Also, a 10x50 binocular is the limit for being able to hand hold a binocular. Even then, you may need a tripod. Check for eye relief or how close you have to hold your eyes to the binocular to get the full field of view. Eyeglass wearers usually require a long eye relief. Usually eye relief of 15mm or more is sufficient for both eyeglass wearers and others. In terms of mechanical design, a porro prism, a roof prism and an image-stabilized binocular, if well made, are fine for astronomy. The U.S. military-specification design is fine. Its focus is obtained by individualized focused eyepieces. The center-focus wheel design, also fine, achieves focus with a center-focus wheel and a right eyepiece diopter. Avoid zoom binoculars. In terms of optics, look for Bak-4 prisms, fully multicoated optics and air-spaced objectives. Make sure the binocular is collimated or there's no uneasy feeling or strain when looking. A field of view of 6 degrees or more is preferred for astronomy. The field of view is the view from edge to edge. The dealer should give you 30 days to try them out so you can return them. To focus a U.S. military-design binocular, screw each eyepiece all the way out from the binocular. You will see a plus and minus sign on each eyepiece. Focus one eyepiece at a time. Pick an object in the distance and focus from the plus to the minus position; that is, focus inward. Before you start focusing inward, put your hand over the objective of the eyepiece you're not focusing. Now focus inward for the other eyepiece. The image will slowly come into focus. Once sharp, stop! Don't focus back and forth or you'll have to start over. Then focus the other eyepiece the same way. To focus a center-focus binocular, select a distant object. First, focus for the left eye by turning the centerfocus wheel counterclockwise until the eyepieces are all the way out. Now cover the right objective with your hand and slowly focus the center focus wheel inward for the left eye until you have a sharp image. To focus for the right eye, turn the right eyepiece all the way out. Cover the left objective with your hand and focus the right eyepiece inward until the image is sharp. If you focus back and forth, you'll have to start over. To hold your binoculars, put your neck strap on and grab the binocular by the barrels with both hands. To hand-hold giant and high-magnification binoculars, try one of the following: 1) Hold the binocular by the ends of the barrels and let the eyepieces rest into your eye sockets. Be careful. 2) Hold the end of the left barrel with your right hand and let the right barrel rest on your right forearm. 3) Prop yourself against a building, wall or tree. A tripod is usually required for giant and high-magnification binoculars. (Adapted from an AAA Observers Group talk.)
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Timothy Ferris' `Seeing in the Dark' on TV September 19
Timothy Ferris is one of the iconic figures in amateur astronomy, and his popular 2002 book "Seeing in the Dark" is a touchstone in the field. An hour-long PBS program with the same title will premiere September 19 at 8 p. m. "`Seeing in the Dark'" introduces viewers to the rewards of...hands-on astronomy--from kids learning the constellations to amateur astronomers doing professional -grade research in discovering planets and exploding stars," Ferris says. "I hope it will encourage many viewers to make stargazing part of their lives, and a few to get into serious amateur astronomy." The film features deep-space images by renowned astrophotographers, and amateur astronomers ranging from casual stargazers to those who have made important discoveries. The program notes that inexpensive telescopes, sensitive digital cameras and the Internet have put amateur astronomers in command of more light -gathering power than the 200-inch Hale telescope at Palomar when it opened a half century ago. Says Ferris, "Hundreds of thousands of casual stargazers are getting in touch with the night sky by using inexpensive computer-controlled telescopes, downloading star charts from the Internet and having observations made for them on professional telescopes through Internet time-sharing programs and educational projects." The "Seeing in the Dark" website--pbs.org/ seeinginthedark--enables viewers to their time and location, view tips on of stargazing, learn more about the in the film and find amateur star part print star charts for getting the most out people and concepts ies.

"New telescopes are coming online all the time, and most are amateur telescopes," Ferris notes. "Every serious amateur astronomer who gets into scientific research adds to the total data-gathering capacity of the planet. Recently the astronomical data-gathering rate has been doubling about every 14 to 18 months. Our aim was not just to inform viewers but to incite them to get outside at night and have a look for themselves." The film moves out in space and back in time, starting with nearby planets, then taking in our galaxy and the Andromeda galaxy. Students will have free access to the "Seeing in the Dark" Internet Telescope (SIDIT) through www.pbs.org/ seeing in the dark. They can register online, then send an e-mail specifying the object they want to image. More than 100,000 objects are within range of the robotic telescope and its digital imaging chip. The website features free stargazing teaching exercises. The SIDIT will be at New Mexico Skies, a high-altitude site near Cloudcroft, N. M., which has supported Internet telescopes. The camera's suitable for imaging galaxies and other deepspace objects, but not planets or the Moon, which are too bright for the instrument. -- Dan Harrison

Letter to the Editor: Amateur Data Sought on Sky Images
To the Editor: A collaboration of scientists from NYU and the University of Toronto is working towards launch of a web service, astrometry.net, that will take as input images of the sky and output meta-data about those images, especially about the mapping of image coordinates to sky coordinates. A principal objective is to make professional and amateur astronomical data interoperable, so that professionals and amateurs can easily access, compare and combine their data. This will provide new opportunities for astrophotography and visualization, calibration, discovery and follow-up of transients, and for research in proper motions, parallaxes and variability.
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In preparing for this project, the scientific team would like to experiment with some high-quality, real amateur data, from CCDs, scanned film and commercial digital cameras. If you have data in electronic form that you'd be willing to contribute to a nascent test bed of amateur astronomical images, the astrometry.net team would love to hear from you. In return, they can provide quantitative meta-data about your images, and the warm, fuzzy feeling of contributing to a new scientific project. For more information, see http://astrometry.net/. To contact the team, e-mail Prof. David W. Hogg, associate professor at NYU: david.hogg@nyu.edu. David W. Hogg


Review: The Telescope's Past, Present and Future
By Lynn Darsh
It's been almost 400 years since Galileo used reports of Hans Lippershey's spyglass to build his telescope and discovered the craters of our Moon and the moons of Jupiter. Ever since, telescopes have been changing our view of the universe and our place within it. Today, optics and telescope design are separate specialties, and astronomers no longer look through most of the remote telescopes that provide their data. To help these astronomers, and us amateurs, better understand the limitations and possibilities of telescopes, Geoff Andersen has written "The Telescope: Its History, Technology, and Future" (Princeton University Press, $29.95). He has 15 years of teaching and research experience in telescope design and holography, and is a research associate in the department of physics at the Air Force Academy. Whether you're considering buying a telescope or still have a Newtonian you made 30 years ago, like me, you will find much valuable information in this book. It explains how telescopes work and brings the reader up to date on the most interesting advances. From explaining the types of telescopes to discussing what they've discovered, Andersen excels at making the complex clear to the non-specialist. His diagrams are helpful, his writing is lively, and his photographs illustrate questions that telescopes have answered or might answer in the future. He includes the first image of an exoplanet; the star field close to Sagittarius A*, the Milky Way's galactic center; and Hoag's Object, an unusually shaped object the size of the Milky Way, about which little is known. Andersen uses only a single equation in the book, the formula that calculates "the size of the Airy spot we get when we focus light of a certain wavelength down with a lens (or mirror) of a certain size." This formula, well known to amateur telescope makers, illuminates what happens in "When Good Telescopes Go Bad," illustrates the problems of imaging the disk of a dim planet from the star it orbits in "Future Telescopes" and calculates what spy telescopes can likely resolve in "Surveillance." Andersen has made an educated guess, based on public information, that the military probably has a six-toeight-meter diameter space telescope in orbit. He estimates it has a resolution of 2 centimeters, can read vehicle license plates and possibly recognize faces. What about interference from our atmosphere? Andersen explains why the blurring effects of the turbulent atmosphere are not as bad when looking down as when looking up by using the analogy of bubble wrap: Put it close to your eyes, and you can't read a book. Put the bubble wrap on the page, and you can read the text. Military research has yielded a number of advances useful for astronomical telescopes. In "Advanced Telescope Techniques," Andersen observes that adaptive optics designs "`corrective glasses' for the precise blurring effect of the atmosphere." He notes that "in 1991, with the Cold War ending, the Air Force decided to declassify the existence of adaptive optics and...presented details on how to make it work. Overnight...astronomy took a giant leap forward unlike any since the development of mirrored optics."

In 1996 Andersen was able to look through the Hooker telescope on Mt. Wilson, newly fitted with adaptive optics, to see the close binary Mira, split visually for the first time. The Hooker had been the telescope to first identify Mira as a binary composed of a red giant and a white dwarf using spectroscopy in 1926.
"What we were seeing was...the very first...image showing the two separate stars. This was only possible using the adaptive optics, permitting us to resolve the 0.6 -arcsecond separation between them. It dawned on me that this was what it was like to be an astronomer--seeing something no one else had seen before.." For all the amateurs addicted to observing, or viewing the spectacular images the Hubble has returned, the book looks at technological developments that have made leaps in astronomical knowledge possible. Telescope mirrors have increased in diameter by a factor of about two every 50 years, and 25% of astronomy research papers are now based on Hubble results. At the same time, new technologies applied to ground-based telescopes since the launch of Hubble may reduce some of the need for a space telescope.
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Briefs: Huge Exoplanet Is a Very Strange Object, Indeed
The largest planet ever discovered is also one of the strangest and theoretically shouldn't even exist. TrES-4 is 1.7 times the size of Jupiter and belongs to a small subclass of "puffy planets" that have extremely low densities. Its mean density is only 0.2 grams per cubic centimeter, about the density of balsa wood. Because of the planet's relatively weak pull on its upper atmosphere, some of the atmosphere probably escapes in a comet-like tail. The planet is about 1,400 light-years from Earth and orbits its star in only three and a half days. Its parent star is about the same age as the Sun but much farther along in its history. It's exhausted all core hydrogen fuel and is on its way to becoming a red giant. A dying star hurtling through space has left a comet -like tail that reveals its history stretching back 30,000 years. The red-giant star Mira A is streaming a cometlike tail 13-light-years long. In the past, the star has shed large stores of carbon, oxygen and other elements. About 350 light-years from Earth, Mira is a variable star that pulsates from dim to bright over 330 days. At its brightest, it's visible to the naked eye. veils of dust and gas, a new study finds. This phenomenon occurs in active galactic nuclei (AGN), which have active supermassive black holes at their cores. The black holes feed on infalling gas and many emit powerful beams of radiation from their poles that shine with the energy of billions of stars. In the newly discovered type of "hidden" AGN, the central black hole is so shrouded by gas and dust that no visible light escapes. Astronomers have found the first direct evidence that some quasars fuel their bright energy emissions by feeding on gas from external sources, probably neighboring galaxies. Using Hubble, they observed that the chemistry of the vortex of gas responsible for a quasar's brightness--1 trillion Suns--suggests that the gas comes not from the massive galaxy containing the quasar, but from a nearby smaller galaxy in the process of merging with the large one. Only quasars with extended emissions regions, which also happen to be powerful radio sources, exhibit the phenomenon. The recent detection of dusty clouds near a supergiant provides the strongest evidence yet why certain stars have mysterious periods of dimness. Astronomers observed a massive cloud of dust particles 30 AUs away from the star RY Sagittarii. It's the closest dusty puff detected around a R Coronae Borealis (R Cr B) star. An very lopsided dusty debris disk around a distant star resembles a glowing blue space needle. Astronomers think the disk around HD 15115 is being affected by hidden planets in the system or nearby stars with very elliptical orbits. One possible culprit: HIP 12545, a star 10 light-years away from HD 15115. Unlike protoplanetary disks, from which planets form, debris disks are thought to be made up of material left over from planet production. The disk around HD 15115 begins at the same distance from its star that the Kuiper Belt does from our Sun, but extends 10 times further to 550 AU. An exoplanet with a year roughly equal to Earth's has been discovered around a dying red giant. Only 10 red giants are known to harbor planets. The new planet circles its bloated parent star every 360 days and is 300 light-years away in Perseus. The red giant is twice as massive and about 10 times larger than the Sun. Its planet is the size of Jupiter or larger. Briefs continued on page 9

A major cosmic pileup involving four large galaxies could give rise to one of the largest galaxies ever. Each galaxy is at least the size of the Milky Way and houses billions of stars. The galaxies will eventually merge into a galaxy up to 10 times as massive as the Milky Way. Spitzer spotted the merger during a survey of a galaxy cluster nearly 5 billion light-years away. Unlike most known mergers, the galaxies are bereft of gas, which fuels star birth, so astronomers predict relatively few stars will be born in the combined galaxy.
Supermassive black holes in young galaxy clusters feast on bountiful gas until little fuel is left, then fade away, a new study suggests. Using Chandra, astronomers tallied the number of rapidly growing supermassive black holes in two galaxy clusters. One group consisted of young-looking clusters very far from Earth, the other of an older group closer to us. The more distant, younger clusters contained 20 times more active galactic nuclei (AGN) than nearer ones. As the cluster galaxies evolved, the AGN faded away. Some galaxies hide the normally bright output of supermassive black holes at their centers behind thick
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Briefs: In Moon Sweepstakes, It's Jupiter 63, Saturn 60
Briefs continued from page 8 A strange moon around Saturn is shaped like a walnut. Astronomers say 4.56 billion-year-old Iapetus got its shape from a super-fast spin that was frozen into place early in the solar system's formation. Running along its midsection, a mountain chain 808 miles long and 12 miles high adds to the moon's appearance. Iapetus' rotation slowed down to its present, nearly 80-day period from once every 5-16 hours. that make up each doublet orbit around each other, and the two pairs circle one another. Astronomers have observed a small group of young stellar "siblings" in a dusty stellar nursery 848 light-years away. The finding, using Spitzer, could reveal more clues about the formation of and interactions among cosmic families made up of hundreds of gravitationally bound stars. The stars are shown as green, yellow and orange specks, sitting atop a black line that runs through the middle of the image. The line is a long, dense patch of cosmic dust and gas, condensing to form stars. Changes in the brightness and color over small areas of the Moon's surface, Transient Lunar Phenomena (TLP), have been observed telescopically for hundreds of years. Using data from decades-old observations, Columbia University researcher Arlin Crotts and colleagues found a correlation between TLP sightings and regions where orbiting spacecraft have detected gas leaking from beneath the surface. TLP could be from inert gases being released from within the Moon due to radioactive decay of uranium-238 and potassium K-40. Only 5,000 to 10,000 years ago, a star familiar to humans detonated and burned with a brightness comparable to a crescent moon. The star's shattered remains are known as the Veil Nebula. Now Hubble has provided three close-ups of the supernova remnants' wispy clouds of dust and gas still careening into space 1,500 lightyears from Earth. There are rope-like filaments of gas in the nebula, which resulted from huge amounts of dusty debris plowing into gaseous surroundings. Electrically charged specks of interstellar dust organize into DNA-like double helixes and display properties normally attributed to living systems, such as evolving and reproducing, computer simulations show. But scientists are hesitant to call the particles "alive," instead saying they're another example of how difficult it is to define life. The data suggest that in space, plasma particles bead together to form string-like filaments that then twist into corkscrew shapes. The helical strands resemble DNA and are electrically charged and attracted to one another. Complex, self-organized plasma structures exhibit the properties to be candidates for classification as inorganic living matter. 9 Briefs continued on page 10

A new moon of Saturn has been discovered, bringing the tally to 60 vs. Jupiter's 63. Initial measurements suggest it's 1.2 miles wide and lies between the orbits of Mehone and Pallene, two moons discovered by Cassini in 2004. The moon is 1.09 million miles from Saturn .
Cassini will perform its closest flyby of Saturn's icespewing moon Enceladus early next year, moving directly into its icy geyser at the southern pole. Cassini will swing within 19 miles of the moon, almost six times closer than the spacecraft's closest pass in 2005. Scientists think the geyser is 90% fine water-ice crystals, but suspect ammonia and ethane gas are also present. A loosely knit band of roving ice boulders orbiting Saturn could be providing raw material for one of its rings. The finding could solve the puzzle of what sustains Saturn's "G-ring" and might be evidence that a Saturnian moonlet was destroyed in an ancient collision. Gring images reveal a bright, curved streak of material near the ring's inner edge composed of icy particles ranging in diameter from less than a centimeter to a meter. Astronomers have spotted a dusty disk in a four-star solar system that could be home to a planet in the making. The swirling disk is around a pair of stars in the quadruple-star system HD 98800, 150 light-years away. One pair of suns blazes brightly, while the other, gravitationally bound to the first pair, appears as little more than faint pinpoints of light. Spitzer detected a gap in the disk that could be evidence of one or more protoplanets. One belt of material in the disk is 1.5-2 AUs from the binary stars and likely consists of fine dust grains. The other, 5.9 AU away, is probably made up of asteroids or comets. A swath of near-empty space separates the belts, inside of which a budding planet might roam. The stars


Briefs continued from page 9 A Pentagon office is taking advantage of the Internet as it studies potential applications for space-based solar power. This marks the first time the National Security Space Office has conducted a study that relies heavily on Internet collaboration. The study is due to be delivered this month. A key component is ongoing discussion on a website hosted by the Space Frontier Foundation, http://spacesolarpower.wordpress.com, which has received thousands of hits since it went online in June. Threatened with cancellation, NASA's Kepler planet-hunting telescope will get to the launch pad by early 2009 without new cash. The price tag has risen several times since 2001. In 2006, believing Kepler's problems were largely in the past, NASA accepted a 21% cost increase, pushing total mission costs above $550 million. This spring, an additional $42 million was requested but rejected. The Kepler team continued to seek more money, but when it saw NASA was serious, came back in July with no cost increase. It will cut six months off the end of the four-year mission, scale back some spacecraft testing, reduce schedule reserve and make some management changes. Ball Aerospace & Technologies, the firm building the spacecraft and instrument, is giving up millions of its fee. Kepler will miss its November 2008 target, but NASA can live with that.

Lectures continued from page 3 The 2007-08 AAA lecture series will feature these other speakers: November 2: Laurence Marschall, Gettysburg College, "Pluto Deconstructed." December 7: Michael Allison, Goddard Institute for Space Studies, "Planetary Time and Seasons--Space Clocks and Extraterrestrial Climates." January 4, Jerry Bonnell, NASA, "Astronomy Picture of the Day." February 1: Nergis Mavalvala, MIT, "Detecting Gravitational Waves: LIGO and the Search for the Elusive Wave." March 7: Arlin Crotts, Columbia University, "Liquid Mirror Telescopes Are Looking Up." April 11: Eric Myers, LIGO Hanford Observatory, "Searching for Ripples in Space-Time with your Home Computer." May 2: Eric Gotthelf, Columbia University, "Juvenile Neutron Stars and their Outbursts." Jovian belts continued from page 2 fractor through a solar filter July 14. But a week later, through the same scope, there were no spots. My projected image of the Sun August 5 using my refractor was just as featureless. But Jupiter continued to provide a show discernable even in a 60mm refractor at 50x. Normally such a view reveals two parallel equatorial belts, but only one belt was visible at 50x in the refractor. Changes in the Jovian atmosphere are widespread and involve mainly the South Equatorial Belt, but also include the zone between the equatorial belts and the North Temperate Belt. The South Equatorial Belt appeared much changed. The area of this belt that follows the Spot normally appears somewhat disturbed fainter than the rest of the belt. However, duri faded and Great Red and a bit ng August

Micki Long is Dead at 66
The AAA mourns the passing of its member Marilyn (Micki) Long, who died April 12 in North Miami, Fla., at 66 after a long and courageous battle against cancer. Micki was an active observer who took a number of trips to see major eclipses, including the total solar eclipse in Africa in 2001 that she wrote about for Ey epiece. She wa s a r etir ed specia l-education teacher in New York City public schools and a 30-year member of the United Federation of Teachers. Micki co-founded a Bulgarian folk dance group, Bosilek, 25 years ago. She danced, and programmed and taught folk dancing. Friends recall Micki as exceptionally devoted to her mother, who died last year at 104. Micki, who made frequent trips to Florida to take care of her needs, is survived by a brother and a sister. -- Dan Harrison
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Events on the Horizon September 2007
M: members; P: open to the public; T: bring your telescopes, binoculars, etc.; C: cancelled if cloudy; HQ: at AAA headquarters, 1010 Park Avenue (between 84th and 85th streets); AMNH: For ticket information, call (212) 769-5200 Check the AMNH's website at www.amnh.org for an Observing at Floyd Bennett Field, Brooklyn, P, T, C Model airplane flying field. For directions, see aaa.org. Tuesday, September 4, dusk to 10 p. m. Next date: October 19 Observing at Cadman Plaza, Brooklyn, P, T, C Next date: October 2 Monday, September 24, 7:30 p. m., P Hayden Planetarium lecture Saturday, September 8, dusk Subject and speaker not announced at press time. Upper Manhattan Observing, P, T, C Inwood Park, 218 Street and Indian Road. Next date: Friday, September 28, 7 p. m. October 6 Stargazing, Carl Schurz Park, Manhattan, P, T, C Saturdays, September 8 and 15 Observing at Anthony Wayne Recreational Area near Bear Mountain, P, T, C, dusk to 3 a. m. For directions, see aaa.org. Next dates: October 6 and 13 Saturday, September 8, 8. p. m. to midnight Star Party at Custer Institute, Southold, N. Y., P, T Major Long Island astronomical groups--Custer, Amateur Observers Society, Astronomical Society of Long Island, Montauk Observatory--and the AAA will gather. Saturay, September 15, dusk Stargazing, Great Kills Gateway National Park, Staten Island, P, T, C Saturday, September 20, 6:30 to 8:30 p. m. Recent Advances in Astronomy Seminar, M, HQ Next date: October 11 Friday September 21, 8 to 10 p. m. Friday, September 28, 6 p. m. Sunset Nature Walk, Stargazing, Robert F. Wagner Jr. Park at Battery Park City, P, T, C A sunset nature walk featuring a nature interpreter and a telescope with a solar filter. Next event: October 19.

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it was darker than the rest of the belt and less disturbed, reversing the usual pattern. Similarly, the normally bright equatorial zone belts were darker than usual. Those north of the North Equatorial Belt appeared darker than normal. A north temperate belt had formed here. The Red Spot was a pale salmon pink and partially surrounded by a Red Spot Hollow being formed on the trailing edge of the Great Red Spot. These views were obtained using my 150mm., 6-inch reflector at 150x. The Jovian changes apparently began during March. A February picture of Jupiter showed the usual Jovian pattern. Another photo revealed that the Jovian Equatorial Zone had darkened. Pictures taken with the Hubble later revealed the South Equatorial Belt had become disturbed. I watched similar large-scale disturbances on Jupiter in 1971 and 1989. Those disturbances lasted several years before the Jovian cloud belts reverted to the usual pattern. The following months should provide interest until Jupiter sinks into the west in October and disappears in November.
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Contacting the AAA
If you want to join, volunteer your time, participate in events, have a question or need to change your address, e-mail secretary @aaa.org, or leave a message at AAA hq: (212) 535-2922. Also, visit us on the web at www.aaa.org. If you're interested in writing an article for Ey epiece, contact editor Dan Harrison at editor@aaa.org or (914) 762-0358.


An Atlas of the Universe Online
By Bruce Kamiat
Http://www.atlasoftheuniverse.com/ is an online atlas of the universe. Though it's been around for a while, this site has been expanded and offers a guide to our place in space and to many objects and structures surrounding us. The site provides three-dimensional schematic maps showing our surroundings at nine scales ranging from 12.5 to 14 billion light-years from the Sun. At the smallest scale, nearby stars are displayed. At the 5,000 lightyear scale, a simplified view of our part of the galaxy is shown, locating us in the Orion Arm and plotting locations of familiar stars and deep-sky objects. The 5 million light-year scale charts galaxies of the Local Group. . The nicest part of this site, however, is the additional information found by scrolling down each page below the basic maps. A map of the Milky Way, for instance, added in 2006 at the bottom of the home page, shows the latest understanding of our galaxy's structure and reveals that our Orion Arm isn't even a major spiral arm but merely "an enhancement of stars and gas between the Sagittarius and Perseus arms." You can follow the NorAmateur Astronomers Association 1010 Park Avenue New York, NY 10028

ma Arm as it divides into the Perseus and Cygnus arms and find the complex origin of the Sagittarius Arm. A discussion of this interpretation is included. At the 12.5 light-year scale, among many additional pages are a map and a list of all stars out to 20 lightyears, a census of those stars by class, and animations to demonstrate orbital dynamics of multiple-star systems (be sure to look at quadruple-star-system examples). On the Local Group page, you'll find a detailed catalog of all Local Group members. Estimated distances and diameters are given, as well as coordinates, classifications, years of their discoveries and lists of references. Galactic remnants such as the Canis Major Dwarf are also there. At 1 billion light-years, the large-scale organization of galaxy superclusters and voids is plotted. Below that, you'll find a list of the nearest superclusters, and maps and much information on each supercluster and its many component clusters, complete with links to online research papers and discussion of related scientific issues. Want to know about Centaurus clusters A3526 and A3627 and read up on what studies of these tell us about the dynamics of cosmic flows and the Great Attractor? Want to study the structure of the Sculptor Wall? This website is a good place to get started.

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