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Journal of the Amateur Astronomers Association of New York November 2007 Volume 55 Number 11, ISSN 0146-7662

EYEPIECE
like our Sun." Younger galaxies were found to be smaller and morphologically irregular, with larger, more symmetrical galaxies the result of mergers and acquisitions.
With Hubble's help, scientists found the young universe was opaque due to the density of free electrons in that period. Then, when the universe was a mere 400,000 years old, electrons were connected to atoms, causing the universe to become transparent, but not yet with stars. Hubble found that star formation peaked when the universe was 7-8 billion years old.

The Unequaled Triumphs of the Hubble Space Telescope
By John Delaney
Freed from the distorting effects of Earth's atmosphere, the Hubble Space Telescope has not only generated profound new discoveries and mounds of research, but has touched the public as few scientific endeavors have.
"It is no longer just a scientific experiment," said Dr. Mario Livio at the AAA's John Marshall Memorial Lecture October 5. "It has become part of our culture." Livio, a senior astrophysicist at the Space Telescope Science Institute, outlined the highlights of the telescope that saw first light in 1990, was repaired in 1993 with corrective optics--unplugging a visual cork and releasing a torrent of images and data--and recently saved from the NASA chopping block by a global outcry. Among the Hubble's most significant discoveries was that that 22% of the universe is dark matter, the mysterious material that emits and reflects no electromagnetic energy. Fully 74% represents what Livio characterized as the biggest challenge facing astrophysicists: the nature of dark energy, which is causing the universe's expansion to accelerate. "It's not that we're clueless, we just don't have enough clues to convict." Hubble has greatly improved our understanding of the distance scale and age of the universe, helping to constrain the "Hubble Constant" and enabling astronomers to gauge the size of the universe and the distances to objects within it. The problem, Livio said, has been corrected and the true estimated age of the universe--13.7 billion years--has a margin of error of just 10%. "Within two years, we'll know within 4%." On galaxy evolution and star formation, Livio showed the deepest optical image of the universe ever taken. "Every point of light...is a galaxy with 100 billion stars

While not leading the way to the discovery of extrasolar planets, the Hubble did lead the way with extrasolar planet discoveries by means of transits. Also, Hubble could glean other features from transiting planets due to the sensitivity of its optics. For instance, the planet orbiting star HD209458 had no moons and contained an atmosphere of sodium, carbon and oxygen. Hubble has also expanded the search for exoplanets to outside the solar neighborhood. "We looked at 180,000 stars in the galactic bulge to find these tiny dimmings of light and discovered 16 planet candidates. I can say with confidence that there are billions of planets in our galaxy."
Supermassive black holes are no longer a theory, but a proven reality due to the Hubble. Astronomers computed that the organized movement of many stars around a galactic center could only be explained by a supermassive black hole, with some, such as in M87, reaching some 3 billion solar masses. And Hubble found that the more massive the bulge, the bigger the black hole. Hubble continued on page 5

Reminder: Starfest Nov. 10--See page 11


What's Up
By Tony Hoffman The Sky for November 2007
It's Leonid Time. T h e fir st -quarter Moon sets around midnight November 17-18, just around the time that the Sickle of Leo swings into view, and with it the radiant of the Leonid meteor shower. At about the same time, Earth crosses the orbital plane of Comet TempelTuttle, the Leonids' parent comet, which may lead to heightened meteor activity on the East Coast. Otherwise, about 30 meteors per hour should be visible from a darksky site. The meteors should get brighter as the night wears on and they hit our atmosphere more head-on. Mars at its Highest. Alt h ou gh st ill a m on t h a wa y from reaching its brightest, Mars is already dazzling. The Red Planet brightens from magnitude -0.6 to -1.3 during November. Mars' disk grows to 15 arc-seconds wide this month, more than large enough for observers with small telescopes to make out surface details. Even better, Mars is in Gemini, about as far north as it ever gets, and thus as high in our sky as we'll ever see it. This minimizes atmospheric distortion. You should be able to see reddish areas as well as dark patches, and perhaps a polar cap. Mars responds well to observation through color filters, which bring out details, including clouds. November 1 Last-quarter Moon at 5:18 p.m.

The gibbous Moon lies near Mars in Gemini on the night of November 26-27. November 3 Moon lies near Saturn and Regulus. November 5 Moon lies near Venus. November 8 Moon lies near Mercury; Mercury is at greatest elongation in morning sky. November 9 Asteroid 1 Ceres at opposition; New Moon at 6:03 p.m. November 11 Moon lies near Antares. November 12 Moon lies near Jupiter. November 17 First-quarter Moon at 5:33 p.m.; Leonid meteor shower peaks. November 23 Moon at perigee, 221,950 miles from Earth, 7:13 p.m. November 24 Full Moon at 9:30 a.m. November 27 Moon lies near Mars. November 28 Venus lies near Spica. November 30 Moon lies near Regulus.

Venus and Saturn Meet Again, Mars Brightens, Jupiter Fades
By Joseph A. Fedrick
On the mornings of October 13 and October 14, Venus and Saturn were within some 3 degrees of each other. Creamy-white Venus was much brighter than duller yellow Saturn and was passing south of it. They made a striking triangular pattern with the bluish-white first magnitude star Regulus in Leo. Although striking, this Venus-Saturn conjunction wasn't quite the spectacle as the June 30 pairing of Venus with Saturn observed by more than 100 people using scopes set up by AAA members on the Brooklyn Promenade. Saturn also looked substantially dimmer than in
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June and even dimmer in October than in September because the rings were becoming more nearly edge on and were reflecting less light back toward us. I observed the growing, brightening disk of Mars October 6 at 6 a. m. with my 60mm f/15 refractor at 100x. The Martian disk appeared coral-pink and gibbous. There was a faint hint of darker smudges on the disk. The season for observing Mars in small amateur telescopes had begun. Jupiter still revealed a fainter South Equatorial Belt Venus and Saturn continued on page 12


A Message from AAA President Richard Rosenberg
Hello, members: This year marks an important anniversary of our club. Eighty years ago, Dr. Clyde G. Fisher of the American Museum of Natural History collected the names of hundreds of persons who might be interested in an amateur astronomy club. On May 10, 1927, less than two weeks before Lindbergh flew the Atlantic, 500 people attended a meeting at the museum. On June 23, the constitution and bylaws were adopted and the Amateur Astronomers Association was born. Its object was to promote the study of astronomy by non -technical methods and to emphasize the cultural and inspirational value of the subject. Before long, the museum started sponsoring the club, aiding it financially and putting facilities and personnel at its disposal. (For more of the early history of the AAA, see Patrick Rizzo 's article "A History of the First 40 Years of the Amateur Astronomers Association " on our website, www.aaa.org.) Those days of sponsorship by the museum are unfortunately a thing of the past. sources, which is where you come in. Soon we'll be asking you to renew your member year. You may also choose to receive S k y & T elescope and/or A stronom y magazines you send your renewal in early (it will still apply to all of 2008), you'll save us the cost We'll send a copy of our new 2007-2008 brochure (hot off the press) and a membership We must provide our own reship. Our dues remain $25 per at a special discounted rate. If and effort of mailing a notice. card to renewing members.

Let me remind you that our annual Urban Starfest is coming up Saturday, November 10 from 6:30 to 10 p. m. in the Sheep Meadow of Central Park; rain date is the following evening. Once again, several members will bring their telescopes. If you lack a scope, come anyway and view Mars as well as several deep-sky objects you're not supposed to be able to see from New York City.

With great pleasure I announce the appointment of Edward Fox to our board of directors. Ed has been our most active members, whether redesigning our website, imaging the skies or helping at mailings. With Marcelo Cabrera, another recent addition to the board, we hope to bring 21st-century technology to the club. Ed es Rachel Connolly, who's now at the University of Louisville and director of the Rauch Planetarium there. served the club well and we'll miss her.
Rich Rosenberg, AAA President, pr esident @a a a .or g, (718) 522-5014

one of Ed and replacRachel

AAA Lecturer Nov. 2 Will Discuss `Deconstructing Pluto'
Dr. Laurence Marschall, professor of physics at Gettysburg College, will address the AAA Friday, November 2 on "Deconstructing Pluto." The free public lecture begins at 6:15 p. m. in AMNH's Kaufmann Theater. "On January 13, 2007, the American Dialect Society chose 'Plutoed' as the 2006 word of the year," Marschall notes. "Plutoed is defined as 'to demote or devalue someone or something,' as happened to the Planet Pluto when the International Astronomical Union decided Pluto no longer met its definition as a planet. "My talk will give the background behind the Plutoing of Pluto: a history of changing astronomical concepts of planets since ancient times, an outline of new discoveries at the edge of the solar system that led to the new definition and a report on the vote in Prague on August 24, 2006 (I might reveal how I voted)." Marschall teaches astronomy, physics and science writing. He joined the Gettysburg faculty in 1971 after receiving his Ph.D. from the University of Chicago. He was awarded the 2005 education prize from the American Astronomical Society for his role in fostering undergraduate and public education in astronomy. Marschall writes a monthly column for N atural History magazine on science books, and is the author of "The Supernova Lecture continued on page 12
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Peering Back to the First Things in the Universe
By Katherine Avakian
The deepest optical image taken by the Hubble shows a kaleidoscopic view of galaxies reaching far back in time. But not even Hubble can see enough back to visualize the universe's first stars. Those "massive, isolated stars, the first luminous objects, were discovered with a supercomputer, not a telescope," said Tom Abel, associate professor of physics at Stanford, in a September 24 Hayden lecture, "The First Things in the Universe." The audience viewed a simulation of how the first star formed. Abel places a high value on the earliest picture of the universe taken by the WMAP satellite showing the Cosmic Microwave Background. He called the universe a dense, hot place 400,000 years after the Big Bang, but it was surprisingly uniform, showing only small fluctuations in temperature and density, "a very simple place." Eventually, the universe expanded further, becoming more transparent as photons traveled between atoms. Gravity made small density perturbations. Abel emphasized the role of gravity, not only as "one of the main ingredients of how we make galaxies," but how it worked in simulating formation of the first star. The computer model Abel and colleagues devised had built-in standards. Their January 4, 2002 article in Science stated, "In comparison to present-day star formation, the physics of the formation of the first star in the universe are rather simple: the chemical and radiative processes in the primordial gas are readily understood; strong magnetic fields are not expected to exist at early times; and...no other stars exist to influence the environment through radiation, winds, supernovae, etc." The program was carefully calibrated. A reporter viewing the simulation described its workings. "Every image that appears on the computer monitor is built from a grid consisting of thousands of individual cells. Within each cell, the computer solves dozens of equations involving gravity, heat flow, and collisions between atoms and molecules....What drives this impressive programming is not computing power but a detailed understand4

ing of stellar physics." (Discov er, December 2002) A summary description of the program was previewed by a "Physics World" editor in its November 15, 2001 issue. "Starting with a flat universe filled mostly with invisible `dark' matter and 6% of ordinary matter, the simulation charts events that occurred some 13 million years after the Big Bang. Small density fluctuations prompted the formation of pre-galactic objects, which merge to form more massive structures. As these objects assemble, the primordial gas collects, cools and sinks to form a cold, dense cloud. Some 140 million years later, the core of this cloud had grown to be 100 times more massive than the Sun and it is sufficiently dense for hydrogen molecules to form. "According to the simulation, this 'three-body' formation of molecular hydrogen prevents the core from breaking up. Instead, a single protostar, similar in mass to the Sun, forms at the centre of the core and rapidly accretes more mass to become a fully-fledged metal-free star. Abel and co-workers predict that the final mass of the star is between 30 and 300 solar masses, although the exact value depends on the detailed physics of the accretion. Moreover, the model predicts that no other stellar object could have formed before this first star died in a supernova." The first generation of gigantic, brilliant stars was short-lived, burning up their hydrogen fuel in a few million years and exploding in titanic supernovae, seeding the universe with heavy elements. Some stars exploded so violently, they collapsed in on themselves, creating black holes which are thought to exist today. Succeeding generations of stars enriched the universe with the elements of which we and our world are made. Abel surmised that "Somewhere between 10,000 and hundreds of millions of stars have helped in making us." A tiny amount of elements--about a finger's worth-comes from the deaths of the earliest stars, whereas most of the rest of us is made up of elements from the death of stars in the present era.


2007 Solar-Eclipse Conference on Hollywood Mountain
By Thomas Haeberle
An Internet group called the Solar Eclipse Mailing list brings together eclipse chasers, amateurs and professionals who relish being under the shadow of the Moon. Most solar-eclipse meetings rarely occur outside of totality, so it was decided to have solar-eclipse conferences during years when no central eclipse occurs. The 10-year-old mailing list has moved to Yahoo Groups and is now moderated by British eclipse chaser Michael Gill. The first international conference was in 2000 in Antwerp, Belgium, followed by one in 2004 in London. In August, the Griffith Observatory in Glendale, Calif., hosted the event. Speakers read like a who's who in eclipse chasing: astronomers Jay Pasachoff and Glenn Schneider, writers and educators David Levy and Dava Sobel, and others who came from numerous countries. Science writer Daniel Fischer talked about seeing the perfect pearls or the phenomenon known as Bailey's Beads, where sunlight shines between the lunar mountains just before being eclipsed. By moving to the edge of the umbral path, the beads can be seen for a minute or longer and not seconds, as would be the case at the central line. Since no corona is seen with annular eclipses, "going to the edge has only advantages. Going inside a kilometer of the edge of the zone is the best place." Dr. John Westfall, professor emeritus of geography at San Francisco State University, discussed a 20-year barrage of [solar] transits, all of Mercury except two of Venus. He's coordinator for transits of the Association of Lunar and Planetary Observers and looks forward to receiving reports for the transits of 2012, 2016 and 2019. Griffith director and astronomer Ed C. Krupp focused on exhibits of the planetarium, especially one that shows the motions of Earth and Moon around the Sun. Showing how eclipses were produced with a physical model imposed unusual challenges. The resulting model successfully shows the relationship between the three orbs. There were technical discussions by 22 year-old student Hana DruckmЭllerovА on image-processing techniques and solar physicist Vojtech Rusin on the corona and how highly structured it is. He used terms such as helmet streamers, polar plumes and corona cavities. Helmet streamers are large cap-like coronal structures with long pointed peaks that usually overlie sunspots and active regions. Prominences or filaments can be found lying at their base. Polar plumes are long thin streamers that project out from the Sun's north and south poles. The study of the corona and what drives it brings professional astronomers and solar physicists to view solar eclipses. Rusin has been on 14 eclipse expeditions. On a lighter note, Levy spoke on "Eclipses as an Inspiration." As a popular writer, he uses the experience to inspire others to do astronomy. Levy is an amateur's amateur who even finds lunar penumbral eclipses magical. As an educator, he likes to teach the Moon as a place and not just some orb that hangs in the sky. He also feels we lost something in the way we communicate what we're learning about in the universe. "We've lost the beauty of how science was explained" as evidenced by 17th century scientific writings. The top speaker for me was Fred Espenak, who spoke on the "Five Millennium Canon of Solar Eclipse." He outlined how these catalogs (Canons of Eclipses) and eclipse maps came to be, which I'll discuss in a future article. Espenak graciously presented his Five Millennium Canon to our club some months ago; it's now part of our library. It will also be present at AAA meetings for review and discussion, perhaps starting this month. Hubble continued from page 1 Thanks to Hubble, gamma-ray bursts, the largest explosions in the universe, were traced to host galaxies where the rays are generated by collapsing stars. And identifying different populations of stars in the same galaxies is now possible. In nearby galaxies such as Andromeda, researchers found a halo of additional stars around the galaxy, and discovered two populations of stars, one about 12 billion years old and the other 7-8 billion years younger. This points to a collision between Andromeda and another galaxy, Livio said. Hubble continued on page 7 5


Astronomical Observing Using Binoculars
By Edward Oravec
In the past two months, I read two articles on use of binoculars for astronomical observing. The first was by Julian Parks in the September Ey epiece. The other was in the October S k y & T elescope by Gary Seronik. Both gave good information on choosing binoculars and how to use them. Neither said much of what can be viewed in binocs and why, at times, they're superior to telescopes. Over decades of observing, I owned and used numerous telescopes and binoculars. I started with a 3power opera glass, graduating to a Zeiss 10x40, then 7x50 and 10x50s. For all-around use, 10x50s were best. In the late '50s, The heavens seemed was 3.5 degrees. The far more open like a ri I purchased a Vixen 16x70 binoc. to open up with these. The field stars were noticeably brighter and chest-field telescope. My major interest in astronomy has of variable stars. I began my program in accelerate until the `50s. In the 16x70s excess of 100,000 observations of 456 including a couple of dozen nova. been the study 1941 but didn't I made well in variable stars,

From the late 40s until the early 70s, The Observers Group made numerous weekend trips to several sites on the north fork of Long Island, including the Custer Institute. We frequently went to see the Perseid Meteor Shower. On clear nights, 6th magnitude stars were visible naked eye. Stars could be seen down to the horizon. The views of Milky Way star clouds were breathtaking in the 16x70 binoculars. Star clusters and galaxies were too numerous to list. I was interested in finding the limiting magnitude of my binocs. I could just see a 10.7magnitude star. Generally the Moon is best observed with a telescope. Many lunar features can be viewed with binocs but in 7x50s, the Moon is just too small. On the other hand, total-solar-eclipse views are greatly enhanced in binocs. I have been fortunate enough to be in the path of totality seven times. The scene in the 16x70s is incredible. One is able to see the extent and color of the outer corona. The AAA had two eclipse trips. The first, in July 1963, was to Bangor, Maine, which was the only eclipse I didn't see under ideal conditions. The second trip was in March 1970 to Virginia Beach, Va. with the sky a cloudless deep blue. The first total I saw was in Ironwood, Mich., a sunrise eclipse. Six OGers made the trip and called it "expedition blackout." A number of AAAers flew to Minneapolis for one day to see an eclipse at the airport. In recent years, it would be rare not to see an Earth satellite cross the field of the binoculars. I have recorded several hundred meteors in the binocs. I hope I have proven that even if you're limited in time, budget and location, binoculars have their place in astronomical observing.

When I lived in southern Westchester, fifthmagnitude stars were visible to the unaided eye and ninth magnitude in the 16x70s on clear moonless nights. Fortunately, I have no problem with dark adaptation. A large advantage is no set-up time but it's important to steady the binocs by leaning them or yourself against some object. In 1985 I saw Halley's Comet, just a large hazy disk, 2nd magnitude, just above the horizon. Some of the best views I ever had of the several dozen comets I have seen were in the 16x70s. I saw Venus numerous times naked eye, standing in a shadow, locating with binoculars, pinpointing it. It's a surprisingly easy naked-eye object. It helps if Venus is near conjunction with the Moon, which is an easy naked-eye object several days after new Moon. In the binocs I have seen Jupiter and Sirius in full daylight. I have seen Mercury several hundred times. Many times it's easily seen without optical aid, but I usually locate it first in binocs. Once you know its position, at times it can be seen naked eye. Once I saw it seven days after superior conjunction with the Sun. I saw Venus less than two days before inferior conjunction. Both sightings were only in binoculars.
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Review: Making Urban Skywatching More Fruitful
By Terrell Kent Holmes
The first thing that should be said about Rod Mollise's "The Urban Astronomer's Guide" (Springer, $39.95) is that the title is inaccurate--in a good way. While urban astronomy is the focus, the bountiful information will benefit astronomers at every experience level, from a first-timer picking out stars from beneath the streetlights to a veteran aligning a scope beneath clear country skies. Mollise has an encyclopedic knowledge of astronomy and a wealth of observing experience, both of which he's happy to impart to readers. Optimizing scope viewing from the city is, as one would imagine, quite a fight with ambient light, inhibiting wavelengths, air pollution and other factors. It's a never-ending chess match, but Mollise knows all the tricks of the trade. He gives advice on how to plan an observing session, what books and other materials to use and what one should expect to see. Mollise also provides many photographs not only of deep-sky objects but of other essentials such as star finders, night goggles and telescopes. He's also compiled an extensive list of objects for readers to pursue, not only tapping the Messier list but the New General Catalogue. Despite Mollise's thorough examination of every aspect of special circumstances regarding stargazing from cities, a question must be addressed: Do the rules of urban observing hold true across locales? Are the lightladen skies in Mobile (where he lives) comparable to those of New York or Los Angeles? Mollise knows, however, that in spite of one's best efforts and hopes, what one sees in the eyepiece is sometimes not up to par. For example, he says of M51, the Whirlpool Galaxy in Canes Venatici, "...in the city it is something of a dud." Several years ago, Vatican astronomer Brother Guy Consolmagno gave a lecture in which he issued a caveat concerning raw star-hopping versus depending on go-to scopes. Consolmagno said that one shouldn't buy fish at a market and call it fishing. That is, don't depend on the ever-popular point-click-and-shoot capability of go-to before gaining firsthand knowledge of the night sky. Sound advice, but Mollise believes it doesn't apply to urban viewing, where star hopping is much more problematic. He insists on an urban astronomer's scope having go-to capability to avoid the frustrations of trying to pick the Hercules Cluster out of a hazy sky in Chicago. The information presented in "The Urban Astronomers Guide" is sometimes written in the style of someone who, excited about a particular subject, rapidly shouts it out to the point of running out of breath. Mollise's enthusiasm sometimes overwhelms the text. He crams a mind-numbing amount of information and arcane terminology into a paragraph, or a sentence, until it becomes virtually indistinguishable. There is faulty sentence structure and fact-checking throughout. For example, he refers to prices in pounds and dollars as though the currencies are exchanged one to one. Moreover, it's inexcusable for a book to contain a sentence with the phrase "these both telescopes." Over time, "The Urban Astronomer's Guide" may be regarded as a bible in the discipline. This would be perfect because it shares a few characteristics with the Good Book: pages filled with many words in small print containing information, instruction and lessons that are vital to understanding and carrying out a method of conduct-in this case, the proper way to observe in the city. Hubble continued from page 5 Hubble has also documented stars and planets. To illustrate the point, Livio displayed an image showing in real time a measured jet outflow from a young star. "You can actually see how the thing evolves." One of the Hubble's biggest opportunities was seeing the collision of Comet Shoemaker-Levy 9 into Jupiter in 1994. "What we saw surpassed our wildest imagination." Astronomers could see what looked like a mushroom cloud on the limb of the planet caused by a fragment. Livio showed a flurry of images: detailed views of Mars, auroras on Jupiter, atmospheric features on Uranus, the Eskimo Nebula and gravitational lensing. Aside from science, the Hubble's biggest benefit are images that have spread everywhere. When asked on "60 Minutes" if Hubble was worth the money, Livio quipped, "It gave us the universe. This is cheap."
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Briefs: Warm Dust Around Star May Become a 2nd Earth
Astronomers have spotted evidence of a second Earth being built around a star 424 light-years away. Using Spitzer, they detected a huge belt of warm dust swirling around a young star slightly larger than our Sun. The dust belt, which scientists suspect is clumping together to form planets, is in the middle of the star system's terrestrial habitable zone where temperatures are moderate enough to sustain liquid water. At about 10 million years old, the star is the right age for forming rocky planets. The system also has the right mix of dusty materials in its disk to form an Earth-like planet. The material mix in the belt is like material found in lava flows on Earth. The initial 42 antennas of the Allen Telescope Array, the first major radio telescope designed to go rapidly through long lists of stars in search of alien signals, were inaugurated last month. Within two decades, it will increase the stellar systems examined for artificial emissions a thousand-fold. The 42 antennas will be able to simultaneously observe several star systems while monitoring at least 40 million radio channels. For its first foray, the antennas will scan 20 square degrees of sky in the direction of the center of our galaxy. Eventually, the array will examine 1 million nearby star systems. New Martian satellite images reveal bright deposits once thought to have been carved by flowing water were created by dry landslides. Results reiterate Mars has been fairly dry in the recent past. While the images are in some cases inconclusive on Martian water, they paint a picture of the surface in unprecedented detail. Researchers also ruled out a hypothesis for an ancient ocean. After months-long delays, the Dawn spacecraft is headed toward Vesta and Ceres in NASA's first sortie deep into the asteroid belt. Researchers hope Dawn will shed new light on planet formation and the solar system's early evolution. Dawn will orbit Vesta between August 2011 and May 2012, then move to Ceres by February 2015. The spacecraft has the most powerful solar arrays ever launched into deep space. Fuel efficiency comes from its three-engine ion drive in NASA's first operational science expedition powered by ion propulsion. New images of Pluto and its moons are 20 times brighter than those taken of Pluto 30 years ago when Charon was discovered. The images will aid in estimat8

ing the sizes of Pluto's satellites Nix, Hydra and Charon. The images came from the adaptive optics system of Keck. Astronomers estimate that Nix and Hydra are less than 62 miles in diameter, vs. 753 miles for Charon and 1,429 miles for Pluto. Ancient gravitational interactions with Venus and Jupiter could help explain some quirks about our Moon's orbit. The Moon's rotation is unusual in that its spin axis is tilted, and it travels along a particularly elongated oval -shaped path around the Earth. Venus and Jupiter may have elongated the orbit slightly by affecting the Moon via their gravities, which exerted a strong tug on the Moon at some time when the planets' orbital periods were aligned with the Moon's orbit. MIT researchers have devised a tether to help astronauts walk across asteroids. The system would wrap all the way around the asteroid. Astronauts will find it hard to work on the surface due to extremely low gravity. The Orion Nebula is nearly 300 light-years closer to Earth than thought, and the age of its stars greater than believed. New measurements shorten Orion's distance from 1,565 to 1,270 light-years. Some stars there, thought to have formed about 1 million years ago, are now pegged at closer to 2 million years old. The two brightest star explosions ever witnessed have been discovered within months of each other. The latest find is supernova 2005ap, which at its peak blazed 100 billion times brighter than the Sun and was twice as luminous as the previous record holder, supernova 2006gy. 2005ap is a Type II supernova, but was 300 times brighter than average Type II explosions. Supernova 2006gy emitted more than 50 billion Suns' worth of light. 2005ap was located 4.7 billion light-years away. A new discovery serves as some of the first direct evidence for a system powerful enough to accelerate particles into cosmic rays. Previously, magnetic fields strong enough to create cosmic rays had never been directly detected. To make the discovery, a team focused Chandra on X-ray hot spots in a supernova remnant a few thousand light-years away in Scorpius. The hot spots Continued on page 9


Briefs: System May be Strong Enough to Form Cosmic Rays
Continued from page 8 brightened cosmic-ray moved, sci shockwave and faded in generation. entists could at 10 million less than a year, the hallmark of Because the hot spots barely peg the speed of the supernova mph. embryonic planets predicted to exist in the three systems are 30, 100 and 133 AU from their parent stars. The first high-def video of Earth from beyond its orbit, 68,350 miles away, was made by a Japanese satellite on its way to the Moon. Kaguya, launched September 14, will investigate the Moon to determine chemical composition, surface/subsurface structure and remnants of magnetic and gravity fields. Onboard equipment will shed light on the electromagnetic field and high-energy particles. The spacecraft's 16.7-hour polar orbit ranges in altitude from 63 to 7,296 miles. Meanwhile, China was due to launch its first lunar probe late last month. A strange gaseous molecule discovered in the atmospheres of Mars and Venus could affect Venus' greenhouse effect. While observing Venus, scientists noted an unusual signature in the mid-infrared region of the spectrum they couldn't identify. Because Mars' and Venus' atmospheres are 95% carbon dioxide, researchers thought the molecule could be a carbon-dioxide isotope. Differently-weighted oxygen atoms let the isotope absorb more energy than normal carbon-dioxide molecules, so it could contribute more to the greenhouse effect. A recently discovered space rock that could one day threaten Earth turns out to be an object seen more than four decades ago but lost in space since. Thought to be a burned out comet that now resembles an asteroid, it's considered a potential hazard because part of its orbit is near Earth's. It's one of 886 known asteroids bigger than 500 feet that pass within 4.6 million miles of Earth. A Pentagon-chartered report urges the U. S. to take the lead in developing space platforms capable of capturing sunlight and beaming electrical power to Earth. Space-based solar power, the report says, has the potential to help the U. S. stave off climate change and avoid future conflicts over oil by harnessing solar power to provide an inexhaustible supply of clean energy. New computer models of 14 types of exoplanets could help planet hunters. The models vary by mass, diameter, composition and where worlds could be found in our galaxy. Some are made mostly of water ice, carbon, Continued on page 10
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A storm from the Sun ripped a tail off a comet, and a NASA satellite captured the event. The crash occurred April 20 when the Sun cast out a coronal mass ejection. The tempest was thrust in the path of Comet Encke, which was traveling around the Sun within Mercury's orbit. As gas swept over the comet, its tail brightened, then was separated from its parent icy rock. Another study shows comets can sometimes slow the solar wind. The Solar and Heliospheric Observatory (SOHO) spotted an unusual periodic comet that orbits the Sun at regular intervals. Only 190 of thousands of known comets are periodic. While many of SOHO's 1,350 detected comets are suspected of being periodic, this is the first proven as such. The new comet takes four years to orbit the Sun. It's an estimated 330-650 feet in diameter. Slushy geysers on Saturn's moon Enceladus erupt from fractures clustered around a hot spot at the South Pole. Researchers found the most prominent jets came from hot spots along four cracks on the moon's surface. The discovery is the first to directly link the tiger stripes and the jets. This could help determine whether a vast liquid ocean and possibly life lie beneath the crust. New calculations show at least 2.1 million-billion years must pass for half of dark matter to decay, if it does at all. Scientists proposed the half life after looking at X-rays from the Bullet Cluster, a cosmic collision of galaxies thought to harbor two massive globs of dark matter. If dark matter can slowly decay, it can also emit radiation, albeit at nearly undetectable levels. Puffy debris disks around three nearby stars could harbor Pluto-sized planets-to-be. The disks orbit within 60 light-years of our solar system. AU Microscopii and Beta Pictoris are an estimated 12 million years old, Fomalhaut 200 million. The objects would be the first evidence of a never-before-observed stage of early planet formation. Fomalhaut is thought to contain at least one other planet in addition to the Pluto-sized planet. The


Briefs: Magellanic Clouds Are Younger than Thought
Continued from page 9 iron, silicate, carbon monoxide or silicon carbide; others are mixtures of these compounds. Rather than assuming exoplanets would be big or small versions of planets in our solar system, astronomers considered all possible types. A pure water planet weighing the equivalent of Earth will span 9,500 miles across, while an iron planet of the same mass will be compressed to 3,000 miles. The Large and Small Magellanic Clouds, dwarf galaxies thought to be the Milky Way's longtime companions, are actually relative newcomers to our neighborhood that are just passing through, a new study says. The finding forces astronomers to rework theories based on long-lasting interactions between the Milky Way and the galaxies. Both galaxies are now seen to have extremely parabolic orbits and entered our neighborhood for the first time 1 billion-3 billion years ago. NASA's Pluto-bound spacecraft, New Horizons, surfed a long tail of charged particles trailing Jupiter. Observations showed huge bobbing bubbles of charged particles, or plasma, and that the structure of the planet's tadpole-shaped magnetotail is surprisingly varied. This could help scientists understand the protective magnetic environment surrounding Earth and other planets. New Horizons also detected another class of very hot charged particles hurtling down the magnetotail, which cooled and slowed as they moved away from the planet. Some particles originated from Io, but others came from the solar wind and Jupiter's atmosphere. A new, intense type of radio burst has been discovered in archived views of the cosmos. The single, shortlived blast of radio waves likely occurred some 3 billion light-years from Earth, and may signal a crash of two neutron stars, the death throes of a black hole or something else. The burst was found in data from a 2001 radio survey of the Small Magellanic Cloud. But based on its location, the burst probably didn't come from the galaxy. Orphaned stars are being born in a vast tail of material stretching behind a faraway galaxy, proving that orphaned stars are much more common than thought. The feature extends for more than 200,000 light-years and was created as gas was stripped from the galaxy. Gas in
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the tail has formed millions of stars. The parent galaxy is 220 million light-years from Earth. Evidence for star formation in the galaxy's tail includes 29 regions of ionized hydrogen glowing in optical light, thought to be from newly formed stars. Scientists believe the stars formed in the last 10 million years. Until now, astronomers couldn't see foreground galaxies outshined by the dazzling quasars behind them. A new technique can pick apart the intense pattern of light emitted by quasars, finding irregularities in the image where "invisible" galaxies are absorbing some of the quasar light. To locate the galaxies, astronomers selected quasars with "dips" in their light signatures. They then searched for galaxies close to the pulse of quasar light. The search was for galaxies from when the universe was 6 billion years old. Seventy percent of the time, a galaxy hiding in the "headlights" of a quasar was found. So far, 14 hidden galaxies have been detected. New measurements reveal Neptune's South Pole is warmer than the rest of the planet, as expected. The region's relative warmth could provide a route for methane gas to escape from the stratosphere, explaining mysterious hot spots. Warmer climes are consistent with the fact that Neptune's Southern Hemisphere, because of the planet's tilt and orbit, has been bathed for about 40 years in the sparse sun rays that can reach Neptune. A year on Neptune lasts 165 Earth years, so summers last 40 years. A NASA mission to find black holes in our local universe restarted after cancellation due to lack of funding last year. The Nuclear Spectroscopic Telescope Array is expected to expand understanding of the origins and destinies of stars and galaxies. Launch is slated for 2011. The spacecraft will map areas of the sky in the light of high-energy X-rays and have 500 times the sensitivity of previous instruments that detect black holes. A supposed meteorite that crashed in southern Peru in September caused hundreds to be ill. But scientists said dust, not gas, caused the illnesses. The crater is 66 feet wide and 16 feet deep, larger than any known meteorite fall since 1947. Astronomers said the meteorite left an elliptical crater and magnetic rock fragments in an impact as strong as an explosion of 4.9 tons of dynamite. Continued on page 12


Events on the Horizon November 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 additional listing of other events. Friday, November 2, 6:15 p. m. AAA lecture, P Laurence Marschall, professor of physics at Gettysburg College, will discuss "Deconstructing Pluto" at the AMNH's Kaufmann Theater. Saturdays, November 3, 10 and 17 Observing at Anthony Wayne Recreational Area near Bear Mountain, dusk to 3 a. m., P, T, C For directions: aaa.org. Thursday, November 8, 6:30 p. m. Recent Advances in Astronomy Seminar, M, HQ Next date: December 13. Observing at Floyd Bennett Field, Brooklyn, P, T, C Model airplane flying field. Next date: December 14.

Saturday, November 17, 10 a. m. to noon Central Park solar observing, P, C At the Conservatory Waters. Next date: December 15.
Saturday, November 17, 1 to 4 p. m. Observers Group, M, HQ Next date: December 15. Saturday, November 17, dusk Stargazing, Great Kills, Staten Island, P, T, C Monday, November 19, 7:30 p. m. Hayden Planetarium Lecture, P, AMNH Peter Ward, University of Washington paleontologist, will discuss links between mass extinctions and shortterm rises in CO2. Current CO2 levels rival past ones.

Saturday, November 10, 6:30 to 10 p. m. Urban Starfest, P The AAA-Urban Park Rangers annual event in Central Park Sheep Meadow. Rain date: Sunday, November 11.
Saturday, November 10, dusk Upper Manhattan Observing, P, T, C Inwood Park, 218th Street and Inwood Road. Next date: December 8. Wednesday, November 14, 7 p. m. Quarterly AAA board meeting, M, HQ Friday, November 16, 8 to 10 p. m.

Handbook, Guide Available
The 2008 Royal Astronomical Society of Canada's Observer's Handbook and the Beginner's Guide are available. Pri copy book. ies), ces are $31.95 per copy (1-4 copies), $20.45 per (5-9 copies), $17.95 (10-24 copies) for the handFor the beginner's guide they're $25.95 (1-4 cop$17.50 (5-9 copies) and $15 (10-24 copies).

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 members @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.

The AAA will order 25 handbooks at $16.95 and 20 guides at $15. For a copy, president@aaa.org. For info on the handbook, http://rasc.ca/handbook/ and on the guide, http://rasc.ca/bog/index.shtml. To order on your own: http://rasc.ca/im/publications/ OH_2008_OrderForm.pdf for the handbook and http:// im/publications/bog2003flyer_back.pdf for the beginner's guide.
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Briefs continued from page 10 Astronomers have spotted and weighed a tiny galaxy 6 billion light-years away. The galaxy, 100 times lighter than the Milky Way, is the smallest galaxy identified at that distance. It's about half the size and one-tenth the "weight" of typical small galaxies closer to Earth. Having coaxed all the life they can out of an 8-yearold ultraviolet light-detecting space telescope, scientists reluctantly turned it off. NASA's Fuse (Far Ultraviolet Spectroscopic Explorer) observatory was tuned to short ultraviolet wavelengths the Hubble can't see. Fuse detected a circle of hot gas surrounding the Milky Way and evidence of molecular hydrogen in Mars' atmosphere. An invisible donut of trapped, hot particles surrounding Saturn is mysteriously bent out of shape. A similar ring-current phenomenon occurs around Earth as a relatively stable donut when present, but images show Saturn's loop is a lopsided mess. Solar wind may be squishing the sunward side of the ring current. Enceladus is responsible for the electric halo, as it spews water vapor from its depths to feed the ring current with oxygen and hydrogen ions. More mysterious is a clump of electrified particles within the ring that rotates in sync with Saturn every 10 hours and 47 minutes, but astronomers are in the dark as to why it moves so quickly. __,_._,___
Amateur Astronomers Association 1010 Park Avenue New York, NY 10028

Venus and Saturn continued from page 2 and a prominent North Equatorial Belt as seen in my 60mm refractor at 50x and 100x. Marked changes in Jupiter's cloud belts were still evident, even in this small instrument at low power. The Jovian disk was shrinking, fading and sinking lower in the southwest as the end of this year's Jovian apparition approached. Lecture continued from page 3 Story." His research includes observational studies of binary stars, very young stars, supernovas and asteroids. Other speakers in the 2007-08 AAA lecture series: 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."

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First Class