Документ взят из кэша поисковой машины. Адрес оригинального документа : http://www.aaa.org/EyepieceFiles/aaa/2007_12_December_Eyepiece.pdf Дата изменения: Sun Feb 22 20:31:05 2015 Дата индексирования: Sun Apr 10 03:44:55 2016 Кодировка: Поисковые слова: agn

Journal of the Amateur Astronomers Association of New York December 2007 Volume 55 Number 12, ISSN 0146-7662

EYEPIECE
News of the October 24 ou t b u r st sp r ea d q u ick ly, and observers quickly trained their telescopes, binoculars and eyes on Holmes, which had brightened to nearly second magnitude. I got my first look at Holmes October 27 from rural Pennsylvania. Despite the nearly full Moon, it was easily visible to the unaided eye. I was struck how beautifully luminous it looked, a bright, yellow center surrounded by a fainter outer circle. It looked like a planetary nebula--a fitting description, as both are caused by much material ejected from their parent object. That same night, Bruce Kamiat, Rich Rosenberg, Ken Taurian, Joe Fedrick, Rik Davis, Peter Tagatac and Ben Cacace observed the comet from Central Park through a variety of instruments. Bruce noticed the disklike structure of the comet "appeared to have a very subtle asymmetry in the binocular view and more so in the telescope," an observation I can confirm.

The Spectacular Comet Holmes: Overachiever of the Year
By Tony Hoffman
For more than 100 years, C om et 17P /H olm es wa s an inconspicuous fuzzball, visible only in large telescopes--so feeble, in fact, that for 58 of those years (1906 to 1964, half of the time since its discovery) it was lost to astronomers. That changed dramatically in late October. On the morning of October 24, a Spanish astronomer reported the comet as undergoing a massive outburst. In little more than a day, the comet's brightness increased nearly half a million times, propelling it to become an easy naked-eye object, even from the city. Numerous observers, including AAA members, viewed this exceptional object, which longtime comet observers have described as the most unusual comet they've ever seen.
The comet's outburst first released an expanding shell of gas, more or less spherical, followed hours later by a similar shell of dust. The comet appeared as concentric circles, with the bright inner dust coma surrounded by the fainter ring of gas. Theories about the outburst-the most spectacular one ever observed in a comet--have included speculation that Comet Holmes was hit by another object, its nucleus disintegrated or the comet's internal structure is honeycomb-like and part of it collapsed. Comet expert Zdenek Sekanina believes the outburst occurred when a pancake-shaped companion object, which had peeled off Holmes, disintegrated. Apparently, Comet Holmes wa s u n d er goin g a n outburst--though not on the scale of this year's--when it was discovered. It was first seen by Edwin Holmes, a London amateur, on November 7, 1892. An avid observer of the Andromeda Galaxy, Holmes was turning his telescope towards his favorite object, when to his surprise, he came across a comet nearly as bright as the galaxy. The comet slowly faded, then briefly brightened in January 1893, then faded again. Holmes, a periodic com-

et that orbits the Sun every 6.9 years, then remained inconspicuous for more than 100 years.

Day by day, t h e com et visib ly exp a n d ed , even a s its surface brightness decreased. Observers with telescopes noted a starlike nucleus of about 8th magnitude embedded within its bright central region. On October 28, many observers, including Tom Haeberle and John Swierzbin, noticed a second bright spot alongside the nucleus. Tom described the spots as looking "like car headlights in a fog." There was speculation the comet was breaking up, but it turned out the second spot was a background star. By October 29, the comet appeared noticeably dimmer to John, observing from Brooklyn. That night, John Delaney noticed how well-defined the outer coma was, despite its translucence.

Comet Holmes continued on page 5


What's Up
By Tony Hoffman The Sky for December 2007
The Year of Two Comets... 2007 will be remembered for two of the most remarkable comets ever observed. It began with the arrival of Comet McNaught (2006 P1), whose brightness and immense tail should cinch it as one of the premiere comets of the century--if not the millennium. It ends after the millionfold increase in the brightness of Comet 17P/Holmes propelled this obscure fuzzball overnight to easy naked-eye visibility, even from the city (cov er story ). Holmes is still easy to observe, ideally placed in Perseus, where it's visible all night, passing nearly overhead around 10. At this writing (November 19), it's a wonder in binoculars or telescope. ...and a Third. Yet a n ot h er com et wit h t h e p otential to reach naked-eye visibility is periodic comet 8P/ Tuttle, which orbits the Sun every 14 years and will race across the northern sky this month. If we're lucky, this comet could reach 5th magnitude in late December. On December 30, Tuttle will lie just a degree from the Pinwheel Galaxy (M33) in Triangulum. A few days later, it will be at its closest to Earth, just 0.25 AU away, its closest approach since before its discovery in 1790. Red Christmas. M a r s r ea ch es op p osit ion on Christmas Eve, when it will shine at magnitude -1.6 near the border between Taurus and Gemini. Six days earlier, it will have made its closest approach to Earth. Although Mars won't be as close or as bright as it was in the oppositions of 2003 and 2005, it will be higher in the sky. The air will be less turbulent, and this should make for clearer viewing of its elusive markings. Good Year for Geminids. I n m id -December, Mars won't be the only attraction in Gemini. The Geminid

Comet Holmes traces a short arc in Perseus this month. meteor shower will peak on the night of December 14, when a two-day-old crescent Moon will do little to interfere with viewing. When Gemini is high in the sky around midnight, observers from dark-sky locations could see up to 100 meteors per hour.

December 1 L a st -quarter Moon at 7:44 a.m.; Moon lies near Saturn. December 5 M oon lies n ea r Ven u s. December 9 New M oon a t 12: 40 p .m . December 14 G em in id m et eor sh ower p ea k s. December 17 First-quarter Moon at 5:18 a.m. December 18 M a r s is closest t o E a r t h , 54.8 m illion miles, 7 p.m. December 22 W in t er Solst ice is a t 1: 08 a .m .; t h e Moon is at perigee, 224,200 miles from Earth, 5:14 a.m. December 23 F u ll M oon a t 8: 16 p .m .; M oon lies near Mars. December 24 M a r s a t op p osit ion , 3 p .m . December 27 M oon lies n ea r R egu lu s. December 31 L a st -quarter Moon at 2:51 a.m.

An Occultation, Comet and Mars Grace the Evening Skies
By Joseph A. Fedrick
I heard a comet wou ld ber 27. Several of us went Park to observe it. Comet and appeared as a pale yel
2

b e visib le t h e n igh t of O ct oto the Great Lawn in Central Holmes had had an outburst lowish fuzzball in binoculars.

It was visible to the naked eye as a 2nd magnitude star in Perseus soon after dusk despite the light of the rising, nearly full Moon. Fedrick continued on page 12


A Message from AAA President Richard Rosenberg
Hello, members: Nothing excites an amateur astronomer more than an unexpected bright Comet Holmes suddenly brightened almost 1 million times! Since then, its this in mid-November the comet is actually larger than the Sun! With luck i A more predictable second comet, Comet Tuttle, should be easy to spot comet. In late October one came our way. coma has continued to grow, and as I write t may continue to be visible into December. with binoculars in December and January.

Urban Starfest was held in Central Park November 10 and we had a terrific time. More than 100 visitors looked through 15 telescopes set up by club members in the Sheep Meadow. I hope you can come to another special event at Belvedere Castle in Central Park on Thursday, December 20. From 7 to 9 p. m. in conjunction with the Central Park Conservancy, we'll show off the bright winter skies, Mars at its biggest and brightest, and comets Holmes and Tuttle. There will also be storytelling, including myths behind winter's constellations. We continue to look for ways to improve the club. In the near future we 'll host our seminar and observers group in an up-to-date environment with laptop computers, Internet access, planetarium programs and digital projectors. A Power Point presentation is being created for our astronomy class. We hope to organize overnight monthly trips to dark-sky locations next year. But some things remain the same. Our lectures at the AMNH continues to draw raves. All this costs money, and we need your continued support. Soon you'll receive a request to renew your membership. Our membership remains $25 per year. If you can, we 'd appreciate an additional tax-deductible donation. AAA board member Dick Tihany has a fine idea: clone yourself. Many of you may know someone interested in astronomy who isn't a club member. Why not tell him or her about the AAA? Rich Rosenberg, AAA President, pr esident @a a a .or g, (718) 522-5014

AAA Lecture December 7: `Planetary Time and Seasons'
Michael Allison, em er it u s scien t ist a t t h e G od dard Institute for Space Studies, will address the AAA Friday, December 7 on "Planetary Time and Seasons-Space Clocks and Extraterrestrial Climates." The free public lecture is at 6:15 in the AMNH's Kaufmann Theater. "As people contemplate briefer daylight and colder temperatures attending the winter solstice, astronomers will bring an understanding of the calibrated measure and geophysical import of planetary time and seasons," Allison says. "The advent of interplanetary spaceflight has provided a window to many related features of extraterrestrial environments and the challenge to define and understand them. From dust storms on Mars to episodic convection of methane on Titan, from multi-millennial advance and retreat of the ice ages to millisecond variation of Earth's solar day, astronomical settings of precession, rotation and spin-orbit coupling hold sway over climates and daily weather of far-flung worlds. "I will engage a brief history of p la n et a r y sola r time and seasons, including the conventions for their accurate measure, as well as the application of modern timing technology to space exploration." Allison did graduate research in space physics and astronomy at Rice University, where he received his Ph.D. Following a National Research Council fellowship at the GISS, he was appointed there as a NASA space scientist in 1984. He conducted research on planetary Lecture continued on page 11 3


Deconstructing Pluto, Not Reconstructing Planets
By Thomas Haeberle
"On January 13, 2007, t h e Am er ica n Dia lect Society chose 'Plutoed' as the 2006 word of the year. [The word was] defined as 'to demote or devalue someone or something,' as happened to Pluto when the International Astronomical Union (IAU) decided it no longer met its definition as a Planet." That's how Dr. Laurence Marschall, professor of physics at Gettysburg College, began his November 2 AAA lecture at the AMNH. On August 24 last year, the IAU issued its cosmoschanging vote at a Prague conference. Marschall, who was there, gave a recap of what may have led to Pluto's demise. He explained how the size of our solar system changed over the centuries. Planets were known to be the seven wonders of the sky, including the Sun and the Moon. In 1543, Copernicus' theory made the big switch in which the Earth took the Sun's place as a planet. In 1781, German-born astronomer W illia m H er schel discovered a new planet from his home observatory in Bath, England. What to name the planet remained a debate for decades. Marschall noted, "Herschel wanted to call it George's Star for the king of England. He felt it was important to give it a name [of a prominent person of the era] that would indicate the time period it was discovered." Instead it would be known as "Herschel's planet," being named so by common usage. It wouldn't be until the discovery of "Le Verrier's planet" or Neptune that it was decided that proper naming conventions would be needed. Marschall didn't dwell on t h e fa ct t h a t m oon s were also considered planets, but noted that the TitusBode law on spacing between planets inspired the search for objects between Mars and Jupiter. A police force of astronomers led to the discovery of not one but four "new planets" at the "X" planet location. Discovery of the real 8th planet, Neptune, and other smaller objects eventually led to reclassifying solarsystem objects. Neptune's discovery by orbital perturbations was a triumph for Newtonian celestial mechanics.
4

In 1905, "another mathematical prediction by Percival Lowell of a trans-Neptunian planet revitalized a new search at his observatory. Clyde Tombaugh in 1930 found it [at Lowell] and it was later named by an 11-year -old English girl." But Pluto would not live up to the expectations of the planet "X" that was causing orbital perturbations of Neptune. Over several decades "it went [from one Earth mass] to .002 Earth mass. The discovery of Pluto was an accident." The CCD electronic camera has been responsi asteroid discoveries increasing 5,000 fold. Not e in the asteroid belt. Lurking out on the fringes solar system were small icy objects theorized ard Kuiper in the 1950s. ble all of by

for wer the Ger

Astronomer Michael Brown fin a lly d iscover ed a Kuiper object larger than Pluto. He felt it was the 10th planet because popular culture called Pluto the ninth. Originally labeled 2003 UB313, the planet's announcement was forced on Brown in 2005 due to pressure of discovery by a competing team. Marschall conceded he might have erroneously said a French astronomer had claimed the discovery under dubious circumstances when in fact it was a Spanish team. Also, it wasn't UB313 (Eris), but 2003 EL61, the "football-shaped" object, that was involved in the controversy. Marschall voted for the new definition, which was somewhat chaotically cobbled together by virtually the entire IAU membership.

New `Cosmos' Series Planned
A new version of the famed "Cosmos" TV series is being planned, but all Hayden director Neil deGrasse Tyson would say last month is that he would host and co -write it. Tyson, who's been on a partial leave since April, still oversees major Hayden activities and is in his office one or two days per week. The released time has been and will continue to be occupied by activities related to media projects. The leave will continue at least through the end of 2008.


Webb Will Be Far More than Hubble 2, Speaker Says
Although the upcoming J a m es W eb b Sp a ce T elescope is popularly viewed as being Hubble 2, it will go well beyond what the Hubble has done, a Space Telescope Science Institute scientist told a CUNY Graduate Center audience October 15. Massimo Robberto noted that instead of just being a substitute for Hubble, the Webb will be in the infrared as well as optical, "a hybrid of Hubble and Spitzer." It won't just see star formation. Even more important is the expansion of the universe. Galaxies move out from the visible spectrum, so the sky becomes black. So to see light, you have to go to the infrared." More specifically, the Webb, which will look back 13 billion years to help us understand the origins of the universe, will go from red to 25-28 micron. "The idea is to see the first generation of stars," Robberto said. Meanwhile, it was announced la st m on t h t h a t t h e Webb is getting a broadband upgrade with SpaceWire that will allow the $4.5-billion scope to capture images of the universe in unprecedented detail. Goddard engineers took SpaceWire, originally developed by the ESA, and adapted it for easier implementation. They designed a small, low-power microchip to send SpaceWire signals at speeds more than 200 megabits per second, more than 10 times faster than most high -def TV broadcasts. This will make information processing faster among the Webb's four science instruments as they talk to each other. So the observatory should capture larger and higher resolution images of space, and be more efficient because it can cover a large swath of sky faster. JWST will act like a digital camera that turns light into digital data. It will make use of 66 million detector pixels, the most on any infrared space scope. Each will collect a small bit of information. Instruments will then process information through SpaceWire to make a complete image. Telescopes tend to have more detector pixels to take bigger pictures of sky. SpaceWire enables larger scopes because more pixels generate more data, and a way to move more data around is needed. Missions can use SpaceWire technology as a standard high-speed electronics package rather than custom-build each time. After Goddard developed it s ver sion of Wire for the JWST, the improved technology available for other NASA missions. Nearly ever U.S. aerospace company has received Goddard's of SpaceWire for government projects, and can technology in commercial applications. Sp a cebecame y major version use the

Because of the huge number of detector pixels, collecting area of the Webb will exceed the width of rocket carrying it into space. The scope will be folded during launch in 2013 and fully deployed to its 21-f width in orbit. --Dan Harrison Holmes continued from page 1

the the up oot

On October 30, I observed the comet from Queens. It was already twice the diameter of October 27, but with a lower surface brightness. Rich and John Swierzbin, observing from Brooklyn that night with 11x80 binoculars, also saw the comet as larger but more diffuse. Despite these changes, the comet remained fairly constant in brightness at about magnitude 2.6. Around November 7, it began to fade notably. To my naked eye, it looked slightly fuzzy on October 30. Up to that point, it had looked absolutely starlike. By November 4, Bruce saw it as clearly fuzzy to the naked eye, in some ways resembling the nearby Pleiades. On November 7, ob ser vin g t h e com et t elescop ically, Tom saw the comet as much larger but lacking much of the detail in its central regions he'd seen the previous week. To his eye, the side of the comet facing the Sun, although still roundish, appeared slightly brighter. November 10 was a big night for observing Holmes. There were two AAA public observing events, Starfest in Central Park and Inwood Park. More than 100 people watched the comet and other wonders at Starfest. From Inwood, Bruce could barely make the comet out to the naked eye, it appearing significantly fainter than the previous week. Telescopically at 25x, he saw a rimlike structure (the bow shock on the comet's sunward side), accented by the slightly darker crescent shape inboard of the "rim." He saw no clear central condensation. Holmes continued on page 6
5


Recent Articles of Interest to Amateur Astronomers
The New York Times, which discussed dark-sky observing-oriented communities in June, has run two more articles relevant to amateur astronomers. On September 14, T he T im es trained its eye on Cherry Springs State Park in north central Pennsylvania, where "On a perfect night, particularly during a new moon, the Milky Way is so bright it casts shadows." The park, in Potter County, 275 miles from New York City, has "become a magnet in recent years for passionate astronomers, as well as for people who just want to tilt their heads back and ponder the vast majesty of the universe....Lured by the dark-sky observing field in the middle of the park, more than 10,000 visitors came to Cherry Springs last year, up 30% from 2005." A Cherry Springs Dark Sky Fund has been established to finance enhancements to the park to make it even better for stargazing. "To cut back on light pollution, for example, all the park's fixtures are shielded." The park's website is www.dcnr.state.pa.us/stateparks/ parkscherrysprings.aspx. "A desire for a starry night a n d con cer n a b ou t rising energy prices are prompting a growing number of cities and counties to dim their lights at night," USA Today r epor ted la st month. "The `dark-sky movement aims to make the Milky Way visible to more people...and save money at the same time by switching to low-intensity outdoor lighting." "Hundreds of cities and counties are trying to bright lights, and at least a dozen states--California, orado, Connecticut, Georgia, Maine, New Jersey, Mexico and Texas among them--have lighting laws ering highways and state projects." curb ColNew cov-

Several cities could soon become dark enough to join Flagstaff, Ariz., as the only dark-sky cities. The National Park Service now includes protecting dark skies in its mission. Several parks, including Death Valley, Joshua Tree and Sequoia, are monitoring light pollution. Lighting around the Old Faithful visitors center at Yellowstone has been retrofitted with reduced lighting. Holmes continued from page 5

An article in T h e T im es O ct ob er 4 d iscu ssed t h e growing number of amateur astronomers who have built an observatory into their house. "Most home observatories have between $10,000 and $40,000 in equipment, including telescopes, computers, refractors, filters and tracking mechanisms, according to astronomy-equipment retailers. The total budget for an observatory can range from $50,000 to more than $500,000, depending on how technologically advanced the equipment, and the size and complexity of the structure."
On September 28, T h e W all S t r eet J ou r n al r a n an article "Digital Age Means We Must Care About Space Weather." A new season of intense sunspot activity that could begin by March and peak in 2012 makes space-weather forecasters worry that "outages and damage could be even greater this time because the world has become increasingly dependant on wireless and cellular electronic networks. We are, therefore, even more susceptible to these sudden gales of solar wind." Intensified sunspot activity could wreak havoc with more flights over the Arctic, "where aircraft are especially vulnerable to radio blackouts and radiation bursts."
6

That night, I saw t h e com et u p st a t e, n ea r W ood stock, N. Y. Under dark skies, it was an obvious, fuzzy glow among the stars of Perseus, to the naked eye. In 12x60 binoculars, it looked like a dull cotton ball about the diameter of the full Moon. In large (20x100) binoculars as well as a small telescope, it looked more like an eye, the oblong or spindle-shaped inner coma surrounded by the ghostly outer coma, which was raggedly symmetrical, as if there should have been a tail. The next night, Rich described Comet Holmes as "beautifully situated near Alpha Persei and its association of stars." Since then, Holmes has continued to expand and fade. Tom and I saw it from Brooklyn November 16, barely visible to the naked eye as it stood near Alpha Persei. What does the future hold for t h is ext r a or d in a r y comet? Will it brighten again in a few months, as it did in 1892, or will observers have to wait until the 22nd century before Holmes again bursts its way out of obscurity?


Review: 2 Cosmologists Plumb Where It All Came From
By Lynn Darsh
To misquote the poet Yeats, "In dreams begin" realities. "Endless Universe: A New History of the Cosmos" (Doubleday, $25.95) begins in 1968 with the authors as boys, Paul J. Steinhardt in Miami and Neil Turok in London, watching "2001: A Space Odyssey." The scene quickly shifts to the recent results of NASA's WMAP mission to investigate the farthest reaches of the visible universe. It continues with the compelling tale of how these boys became cosmologists and collaborated in the exploration of space and time in a quest to answer the question "Where did it all come from?" Steinhardt, now at Princeton, and Turok, at Cambridge, show the reader the early Greeks who thought the world was born in fire had something in common with contemporary cosmologists. As the Big Bang model was refined by contemporary particle physicists and cosmologists to include recent experimental results, the theory became more complicated and arbitrary. As visible matter, d a r k m a t t er , d a r k en er gy a n d inflationary energy became important components of the standard model, both Steinhardt and Turok became dissatisfied with the implications of eternal inflation and with the use of the anthropic principle in a scientific explanation of our universe's set of physical laws. Edward Witten, working with Petr Horava, had created a new model, a geographical picture using 10 dimensions, called M theory. Burt Ovrut gave a talk at a conference Steinhardt and Turok organized in 1999, asserting that M theory should get "special attention because it offered insights into fundamental physics and may provide the most direct way to relate M theory to laboratory experiments." Steinhardt and Turok immediately and separately realized the two parallel branes of M theory might "produce a big bang" when they collided. They began collaborating on a lt er n a t ive t h eor ies of a cyclic universe. Steinhardt and Turok introduce "this more ambitious alternative, known as the cyclic model. According to this picture, the Big Bang isn't the beginning of space and time but, rather, an event that is, in principle, fully describable using physical laws. Nor does the Big Bang happen only once. Instead, the universe undergoes cycles of evolution. In each cycle, a big bang creates hot matter and radiation, which expand and cool to form the galaxies and stars observed today. Then the expansion of the universe speeds up, causing the matter to become so spread out that space approaches a nearly perfect vacuum. Finally, after a trillion years or so, a new big bang occurs and the cycle begins anew. The events that created the large-scale structure of the universe today occurred a full cycle ago, before the last big bang." Steinhardt and Turok cla im t h a t cyclic t h eor y better explains the "flatness, uniformity and large-scale structure of the universe" in a way that's more parsimonious, more selective and uses fewer ingredients than the inflationary big-bang model. This story is without an ending. Further experiments are needed to conclusively determine whether the universe began in the fireball of the Big Bang. Some-- perhaps most--theoreticians believe the evidence could come soon as more precise measurements of the lingering effects of that explosion are made by new spacebased, ground-based and balloon-based instruments. Steinhardt and Turok think these efforts will fail to find that evidence. They offer a compelling alternative theory about how our universe evolved that's receiving serious consideration and becoming the leading contender to the inflationary Big Bang model. If you're fascinated b y gr ea t cosm ologica l q u estions, the latest news from the frontiers where theory meets reality testing in outer space, and how modern scientists collaborate to develop multi-dimensional new theories, this book is for you. Its lucid writing introduces complex ideas using well-chosen everyday analogies and simple diagrams, instead of mathematics. The interested amateur doesn't need to have formally studied physics or astronomy to understand the scientific theories and testing methods presented. The book is a great science read that could become a classic if research results refute the Big Bang model and Steinhardt and Turok's cyclic model is adopted.
7


Briefs: Fifth Planet Far Away is Like Cousin to Earth
A fifth planet in a distant star system t h a t look s lik e a cousin to Earth has been discovered. The Sun-like star 55 Cancri harbors the most planets discovered outside our solar system. The existence of the fifth took 18 years to confirm. It's 45 times more massive than Earth but a similar distance away from its sun and might be similar to Saturn in composition and appearance. 55 Cancri, 41 light-years away towards Cancer, is visible with binoculars. It's about the same mass and same age as our Sun. A huge gap separates the four inner planets, close to the star, from the outer planet. They're as big as Neptune or bigger. The new planet lies within the star's habitable zone. Though it's a giant ball of gas, liquid water could exist on unknown rocky planets in the system. Such a planet could be in the nearly 700 million-mile-wide space separating 55 Cancri's inner planets and its outer one. The planet was found using the wobble technique. Only one other star, mu Ara, has four known planets. Astronomers have found t h e b est sola r t win ou t of four known candidates. HIP 56948, 200 light-years away, has a similarly low quantity of lithium, a lightweight byproduct of fusion reactions that power stars. The mid-sized star, in Draco the Dragon, may be 1 billion years older than the Sun's 4.6 billion years. Other solar twins previously proposed were 18 Scorpius, HD 98618 and HIP 100963. Their lithium contents are dramatically higher. Searches for solar twins are important because the Sun is a baseline for many types of studies, but is too close and bright to study like distant stars. Three exoplanets, a m on g t h e h ot t est wor ld s found, were discovered by the Wide Angle Search for Planets project, dedicated to the discovery of large gas planets orbiting very close to their stars. The worlds, orbiting different Sun-like stars, were found using the transit technique. WASP-4 and WASP-5 are about 500 light-years away in Phoenix. WASP-3 was found using a camera. The newfound hot Jupiters orbit 20-40 times closer to their stars than Earth does. The tight orbits mean the planets are tidally locked to their stars. Temperatures on their star-facing sides reach up to 3,140 degrees. A European spacecraft u sed r a d a r t o p r ob e on e of the youngest and most mystifying deposits on Mars. The ESA's Mars Express orbiter studied the Medusae
8

Fossae Formation (MFF), which straddles a divide between the highlands and lowlands near the equator. MFF deposits have remained an enigma partly because they're "stealth" regions that give no radar echo from certain wavelengths of Earth-based radar. While the deposits absorb radar wavelengths between 1.4 and 5 inches, Mars Express used its sounding that operates at wavelengths of 164 and 328 feet. That means radar waves can pass through MFF deposits and bounce off the solid rock beneath, creating a subsurface echo image. New data show the MFF are massive deposits more than 1.5 miles thick in some places. They could be volcanic ash deposits, wind-blown materials eroded from other Martian rocks or ice-rich deposits that formed when the spin axis of Mars tilted over and made the equatorial region colder. Scientists are puzzled how material from wind-blown dust could be miles thick and not compacted under other material. An enormous cold spot in the universe cou ld b e explained by a cosmic defect in the fabric of space-time created shortly after the Big Bang. If confirmed, the finding could provide a long-sought clue about how the universe evolved. Scientists think that shortly after the Big Bang, exotic particles transformed into the particles we know. Physicists say defects happened during transitions of the early universe and took different forms. The team thinks a cold spot in the cosmic microwave background (CMB) represents the most complex kind of cosmic defect, a 3-D structure called a texture. Scientists analyzed the cold spot, which spans 1 billion light-years, finding properties consistent with a texture. If the spot is a texture, scientists could discriminate among different theories for how the universe evolved. Other scientists say the team's case for a cosmic defect is weak, that it 's likely a random fluctuation. Some recently attributed the CMB cold spot not to a cosmic defect, but to an enormous hole in our galaxy, devoid of even dark matter. The mineral composition of a n ea r -Earth asteroid with a slight chance of hitting Earth in 2036 has been determined. By analyzing reflected sunlight, scientists say Apophis is a good match for a rare type of stony meteorite, a type LL chondrite. These rocks represent just 7% of known meteorites that fall to Earth. The finding Continued on page 9


Briefs: 3 Martian Volcanoes May Be Dormant, Not Extinct
Continued from page 8 could help plan missions to explore Apophis or protect Earth. Apophis, 158 million miles from Earth, won't be visible again for several years. In 2029, it will pass within 22,000 miles of us. There's a 1 in 45,000 chance it could be on a collision course with Earth in 2036. New research su ggest s t h r ee M a r t ia n volca n oes may be dormant, not extinct. Instead of Mars' crust moving over stationary magma "hot spots," as on Earth, researchers think the plumes travel. Each volcano, in the Tharsis region, is 186 miles across. Images suggest they've been active in the past 2 million years and might still be. Sparse impact craters near them indicate relatively recent eruptions. The volcanoes are similar in formation. However, each erupted in distinct ways that allowed determining ages of the eruptions. Invisible twisted magnetic-field lines h elp st a r s spiral into life, according to a new model. It suggests excess material and energy are borne away from a protostar along helical magnetic-field lines surrounding the star. This carries away enough angular momentum to allow a spinning cloud to undergo the final phase of collapse necessary to become a star. The model predicts field lines around a cloudy stellar womb get twisted by the womb's rotation. The model is based on observations of infrared light emitted by particles surrounding HH 135 -136, a protostar cloaked in a molecular cloud 9,000 light -years away. Interstellar grains apparently become aligned to the magnetic field. The model predicts helical magnetic field lines around HH 135-136 extend 50,000 AU from the protostar. Material is believed ejected from the system at more than 200,000 mph. Embarking on a 10-year, t h r ee-stage Moonexploration program, China launched its first lunar probe. In 2012 there will be a Moon landing with a rover. In the third phase, five years later, another rover will return to Earth with soil and stone samples. The probe will use stereo cameras and X-ray spectrometers to map three-dimensional images of the surface and study Moon dust. The satellite will explore for a year. The German government is p r op osin g t o b u ild a lunar orbiter at a cost of up to $508 million. The mission could be launched in 2012 and would orbit at 31 miles. With Europe's exploration package struggling for funds, some ESA and European government officials have questioned the wisdom of Germany's solo lunar orbiter. Hundreds of "missing" black holes h a ve b een found in dusty galaxies billions of light-years away. The finding is the first evidence that most, if not all, massive galaxies in the distant universe spent their youths building supermassive black holes at their cores. It could also help answer how massive galaxies such as our Milky Way evolved. A team detected unusually high levels of infrared light emitted by 200 galaxies far away. They think the light was created by material falling into quasars at the center of the galaxies. The newfound quasars confirm supermassive black holes play a major role in star formation in massive galaxies. The observations suggest massive galaxies steadily build up stars and black holes simultaneously until they get too big and black holes suppress star formation. The new quasars also suggest collisions between galaxies might not be as important for galaxy evolution as thought.

The heaviest "small" black hole h a s b een d iscovered, and its mass of 24-33 times that of our Sun defies current theories to explain its formation. The previous record holder was a 16-solar-mass black hole in galaxy M33 announced two weeks earlier. The newfound object belongs to a class of black holes formed during final death throes of massive stars. These stellar black holes are generally around 10 solar masses. The new black hole is in the dwarf galaxy IC 10, 1.8 million light-years away in Cassiopeia. The host star from which the black hole formed was an estimated 60 or more solar masses.
The earlier record (see abov e), a stellar black hole much more massive than thought possible, puzzled astronomers. The 16-solar-mass black hole orbits a companion star in the spiral galaxy Messier 33, 2.7 million light-years from Earth. They make up the system known as M33 X-7. The black hole is the most distant stellar black hole ever observed. Findings could help improve formation models of binary systems with a black hole and a star. The companion star passes directly in front of the black hole as seen from Earth once every three days, Continued on page 10
9


Briefs: Most Distant Stellar Black Hole is Discovered
Continued from page 9 eclipsing its X-ray emissions--the only known binary system in which this occurs. This odd arrangement allowed calculating the pair's masses precisely. Black holes often are thought of a s en d less p it s in space and time that destroy everything they pull toward them. But new findings confirm the reverse is also true. They can drive extraordinarily powerful winds that push out and force star formation and shape the fate of a galaxy. Astronomers had theorized that accretion disks give off winds that shape host galaxies. To attempt to observe the winds, they investigated a galaxy 3 billion light-years away. At its core lies a quasar originating from the superheated gas of a black hole's accretion disk. Light from the quasar was scattered by electrons in super-fast gas. The way this light was scattered suggests the gas was rotating at speeds similar to the accretion disk's rate of spin. So they confirmed the accretion disk was launching wind. Researchers will next probe if these disk winds are launched only when the black hole is growing rapidly, whether just by quasars, which have the most massive black holes, or by all active galactic nuclei. The most energetic particles in t h e u n iver se lik ely come from enormous black holes nestled in the centers of traumatized galaxies. Where these particles originated has been a source of speculation, from gamma -ray bursts to decaying dark matter. Researchers found the sources of the cosmic rays aren't uniformly distributed across the sky. Instead, they appear to be coming from energetic supermassive black holes in the hearts of some galaxies. Researchers traced 20 of 27 high-energy cosmic-ray events to 20 known active galactic nuclei (AGN). There's less than a 1-in-100 chance correlation between cosmic rays and AGNs. The cosmic rayspewing AGNs are estimated within 326 million lightyears of the Milky Way. While the new study links cosmic rays to AGNs, further studies are needed. But if there's a high-energy cosmic ray, it's more likely there will be AGN with it. A massive explosion in t h e d eep r ea ch es of sp a ce stemmed not from one dying star, as is typical, but from two dead ones that collided. Two white dwarfs slowly spiraled into each other last year to touch off a supernova
10

explosion in a spiral galaxy 300 million light-years away. Originally, astronomers thought supernova SN 2006gz was another example of a white dwarf stealing material from a partner star. But a closer look revealed signs of extra carbon and silicon, hallmarks of a smashup between two white dwarfs. SN 2006gz was brighter than expected, suggesting its origins included more material than the 1.4-solar-mass limit of a white dwarf. Scientists tested a floa t in g sola r t elescop e t h a t hovered high in the atmosphere tethered to a large balloon. The helium balloon and its attached gondola of scientific instruments reached an altitude of nearly 23 miles and remained aloft for 10 hours, capturing images and collecting other data of the Sun's surface. The test clears the way for Sunrise, a long-duration polar balloon flight planned for 2009 that will study magnetic fields on the Sun's surface with a 1-meter lens, the largest solar telescope ever deployed. New-generation balloon-borne telescope missions will cost less than sending instruments into space. Instruments could be recycled and updated. The telescope's large lens will give it resolution more than double space-based instruments and can image features on the Sun's surface as small as 19 miles across. NASA extended t h e a ct ivit ies of t h e M a r s r over s Spirit and Opportunity for a fifth time. This could keep them active through 2009. The rovers landed in January 2004 on a mission originally planned to last 90 days. Opportunity has driven 7.19 miles and has returned more than 94,000 images. Spirit has driven 4.51 miles and has returned more than 102,000. Enormous bubbles of plasma t r a p p ed wit h in Earth's magnetic fields have been fully mapped for the first time. Scientists think the bubbles of ionized gas, convection cells, are strongly affected by pummeling from solar wind. Future observations of the cells could aid in monitoring violent solar outbursts. Convection cells high above Earth's polar caps are made of plasma, highly erratic electron-stripped gas. New statistical maps show convection cells fluctuate between two and four. A massive galaxy is st ea lin g 1 b illion su n s wor t h of gas from a smaller, younger galactic neighbor. The gas, 1,340 degrees, is great for making stars. The robber, Continued on page 12


Events on the Horizon December 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 Monday, December 3, 7:30 p. m. Hayden Planetarium Lecture, P, AMNH Astrobiologist Chris Impey of the University of Arizona will explore our search for life in the universe. Friday, December 7, 6:15 p. m. AAA Lecture, P Michael Allison, emeritus scientist at the Goddard Institute for Space Studies, will speak on "Planetary Time and Seasons--Space Clocks and Extraterrestrial Climates" at the Kaufmann Theater of the AMNH. Saturday, December 8, dusk Upper Manhattan Observing, P, T, C Inwood Park, 218th Street and Inwood Road. Tuesday, December 11, 7:30 p. m. Hayden Planetarium Lecture, P, AMNH Adam G. Riess, professor of astronomy and physics at Johns Hopkins and a scientist at the Space Telescope and Science Institute, will discuss dark energy. Thursday, December 13, 6:30 p. m. Recent Advances in Astronomy Seminar, M, HQ Next date: January 10. Friday, December 14, 8 to 10 p. m. Observing at Floyd Bennett Field, Brooklyn, P, T, C Model airplane flying field. Next date: March 14

Saturday, December 15, 10 a. m. to noon Central Park Solar Observing, P, C At the Conservatory Waters. Next date: January 26 Saturday, December 15, 1 to 4 p. m. Observers Group, M, HQ Next date: January 26. Thursday, December 20, 7 to 9 p. m. Stargazing and Storytelling, Belvedere Castle, midCentral Park at 79 Street, P Join the AAA and the Central Park Conservancy for a tour of the night sky, including Mars and the Orion Nebula. Storytelling begins at 7. We'll then head outside for observing. Bring your own binoculars or telescope. Lecture continued from page 3 dynamics and participated in several spaceflight projects. His published research includes an inference of a probable super-solar enrichment of oxygen on Jupiter, the first identification of Saturn's polar hexagon as a planetary Rossby wave and efficient algorithms for planetocentric solar timing on Mars and Titan. Retiring from NASA in 2005, Allison works part time on planetary studies at GISS, provides support to the upcoming Juno microwave orbiter mission to Jupiter and is adjunct professor of astronomy at Columbia University. The 2007-08 lecture series continues with these speakers: J a n u a r y 4, J er r y Bon n ell, 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
11

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.


Briefs continued from page 10 3C 326 North, is about the mass of the Milky Way. Its victim, 3C 326 South, is half its mass. They're close enough to perturb each other gravitationally and might eventually collide. This is the best example of large quantities of gas being heated and siphoned from one galaxy to another. The event is 1 billion light-years away. The best 3-D map of the cosmos h a s got t en b et ter, thanks to an astronomer's years of cleaning up satellite data. The fresh look at almost 118,000 stellar bodies, the Hipparcos catalog, boosts the database's accuracy by up to five times and doubles its useful information. The catalog provides measurements in astronomy. The catalog's updated version is part of a new book, "Hipparcos: The New Reduction of the Raw Data." How much Io's volcanoes a n d ch u n k s of fr ozen gas contribute to its atmosphere has long puzzled scientists. The New Horizons spacecraft recently documented the Jovian moon's glowing aurora, providing a chance to solve the mystery. Io's volcanoes spew out sulfur dioxide, almost all its atmosphere. As Io rotates from daylight into darkness, going to -226 degrees, the gas freezes into a solid. The atmosphere then collapses so volcanoes are its only source. Because Io's volcanic gas stays warm enough not to freeze and creates glowing auroras, scientists could gauge how much volcanoes supply Io's atmosphere by measuring the nightside aurora. A new instrument cou ld p r ovid e a t ech n iq u e for measuring the extreme ultraviolet range of solar radiation without optical tools such as mirrors and lenses. Light-measuring spectrometers suffer from loss in instrument sensitivity and degradation in space. The opticsFedrick continued from page 2 A peek at the Moon using 10x 50 binoculars owned by Bruce Kamiat revealed it was occulting the Pleiades. The occultation was already in progress as the Moon rose and by 8 the occultation was over. I observed the comet with my own pair of 10x50 binoculars for the next two weeks as it drifted very slowly in Perseus, becoming more diffuse and somewhat dimmer. Observing from the Bronx during late October and early November, each evening around 10, I saw Mars begin to appear as a bright coral-pink light emerging from behind the trees to my northeast. It was still very low in thick turbulent air near the horizon so I didn't train my telescopes at it. Mars promised to be quite spectacular in late November and December, rising earlier, higher and brighter.

Amateur Astronomers Association 1010 Park Avenue New York, NY 10028

Forwarding and Address Correction Requested 12

First Class