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Journal of the Amateur Astrono mers Association of New York August 2011 Volume 59 Number 8 ISSN 0146-7662

EYEPIECE
Zone 2 is a zone of moderate ambient lighting. Vision is adapted to moderate light levels. Lighting may typically be used for safety and convenience, but isnt necessarily unifor m or continuous. After curfew, lighting may be extinguished or reduced as activity levels decline. Zone 3 has moderately high a mbient lighting. Ther e would be areas of activity where vision is adapted to moderately high light levels. Lighting is generally desired for safety, security and/or convenience a nd is often unifor m and/or continuous. Lighting ma y be extinguished or reduced in most areas as activity declines. Zone 4 has high a mbient lighting. Ther e would be areas of activity wher e vision is adapted to high light levels. Lighting is generally consider ed necessary for safety, security and/or convenience and is mostly unifor m and/ or continuous. After curfew, lighting may be extinguished or reduced in some areas as activity levels decline. The second innovation limits the a mount of light used

2 Groups Release Much-Awaited Model Lighting Ordinance
By Dan Harrison
After a gestation period of seven years, the International Dark-Sky Association (IDA) and the Illuminating Engineer ing Society (IES) released their muchanticipated Model Lighting Ordina nce (MLO) June 15. The groups ter med the MLO "a valuable guide for environmentally r esponsible outdoor lighting in North America" and said it would " encourage broad adoption of comprehensive outdoor lighting ordina nces without devoting extensive staff time and resources to their development." The MLO "is designed to help municipalities develop outdoor lighting standards that reduce glare, light trespass, and skyglow." The MLO offers what the groups call three innovations to outdoor-lighting regulation. The first is five lighting zones to classify la nd use, with appropriate lighting levels for each, enabling the MLO to be customized. They range from a zone for pristine natural environments, with limited outdoor lighting, to one for limited application in areas of extensive development in large cities. Zone 0 would have no ambient lighting because it contains areas wher e the environment will be seriously affected by lighting. Impacts would include disturbing flora and fauna and/or detracting from huma n enjoyment of the envir onment. In this zone, human activity is subordinate in importance to nature. Vision is adapted to total darkness, and people expect to see little or no lighting. When not needed, lighting would be extinguished. Zone 1 would have low ambient lighting. The zone has areas wher e lighting might affect flora and fauna or disturb the areas character. Vision is adapted to low light levels. Lighting may be for safety and convenience but isnt necessarily uniform or continuous. Most lighting would be extinguished or reduced as activity declines.

Model Lighting continued on page 11

Legislators Inert on Light Bills
By Dan Harrison
The New York State Legislature adjourned June 25 without acting on identical light-pollution bills introduced by Nassau Republica n State Senator Carl L. Marcellino and Manhattan Democratic Assemblywoman Linda B. Rosenthal. The bills wer e stuck in committee. For a dozen years, light-pollution legislation has failed to become la w. It usually passed the Assembly but failed Legislators continued on page 3


What's Up
The Sky in August 2011 By Richard Rosenberg
August's Evening Sky. Mercury is too near the Sun to be seen. Late in the month, look for it in the mor ning sky. Saturn is getting low: At midmonth it will set at 10 p. m. Still domina nt are the Summer Triangle and the Milky Way. Appearing in the east are the faint constellations of autumn, brightened somewhat by Pegasus and Andromeda. August's Morning Sky. Jupiter in Aries rises around midnight, and Mars in Gemini follows about three hours later. Late in the month, Mercury can be seen befor e sunrise, but Venus is too close to the Sun to be seen. All the bright winter stars in Auriga, Taurus, Orion, Gemini, Canis Minor and Canis Major can be seen. Two bright asteroids, Vesta and Cer es, are currently up, and its possible to spot both this month with a suitable scope and sky. Vesta usually appears as the brighter of the two because of its relative closeness to Earth and inherent brightness. On August 6, Vesta is at opposition: Sun, Earth and Vesta lie in a straight line. Look for it on that date 4А from the fourth-ma gnitude star 24 Capricorni. Ceres is one constellation east, in Aquarius. In August, it brightens from magnitude 8.4 to 7.8. At opposition September 16, its magnitude will be 7.6. On that date, look for it only half a degr ee to the right of the star 2 Ceti, the asteroid having moved into Cetus. The Dawn spacecraft went into orbit around Vesta on July 16, and begins its science mission this month. After about a year, Dawn will hea d for Ceres and view it beginning in February 2015 August 1 Aster oid Cer es is stationary, and begins moving from east-to-west relative to the stars. August 3 The crescent Moon is about 8А below Saturn. August 4 The Moon is 3А below Spica. August 6 First Quarter Moon at 7:08 a. m.; Asteroid Vesta is at opposition. At magnitude 5.6, it may be seen with the na ked eye from a dark site. August 7 This mor ning, Mars is less than 1А south of cluster M35. August 10 The gibbous Moon will occult (cover) the
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bright (ma gnitude 2.9) star Pi Sagittari from 10:14 to 11:22 p. m. August 12-13 The Perseid meteor shower peaks tonight, but a full Moon will overpower most meteors. August 13 Full Moon at 2:57 p. m. August 16 Venus in superior conjunction, entering the evening sky; Mercury in inferior conjunction, entering the morning sky, August 19 This morning Mars is 1НА south of thirdma gnitude Epsilon Geminorum. August 21 Last-quarter Moon at 5:54 p.m. August 22 The Pleiades are about 3А above the Moon this morning; Neptune is at opposition, rising at sunset and setting at sunrise. August 25 Mars is 3МА left of the Moon this morning. August 27 Mercury, now in the morning sky, is 8А lower left of the Moon. August 28 New Moon at 11:04 p. m. August 30 Jupiter stationary, begins r etrograde motion. August 31 Back in the evening sky, Saturn is upper right of the Moon and Spica is upper left of the Moon. For more infor mation on the Inter net, go to: http:// w.aaa.org/month1108.

Jupiter and Saturn in July
By Joseph A. Fedrick
Jupiter was still an early morning object as of early July but was beginning to rise early enough so that by July 7 it was high above the tree line to my east by 5 a. m. Its appearance in the telescope was radically changed from last year. The South Equatorial Belt (SEB) had been fully revived so Jupiter displayed two dark brownish equatorial belts in my 60mm f/15 achromatic refractor at 100x. The Great Red Spot (GRS) was easy to spot last year even with only 60mm of aperture due to its dark reddish color and sharp contrast with the nearly invisible SEB. This year the GRS has faded so that on July 7, it was, at best, barely detectable at the threshold of r esolution with my 60mm scope at 100x. The SEB was partially split into two gray-brown belts, while the North Equatorial Belt wasnt split, was slightly narrower and had a slightly darker gray-orange-br own coloration. Paler belts of a grayish coloration wer e detectable in the higher latitudes of Jupiter. Separating the grayish belts wer e paler gray or ivory white zones. Jupiter and Saturn continued on page 10


A Message from AAA President Richard Rosenberg
Hello members: Lecture chair David Kraft is great at retaining noted spea kers for our lecture series. This year hes topped himself. To lead off the 2011-12 series October 21, our speaker will be Freema n Dyson of the Institute for Advanced Study. Other speakers include Elena Aprile of Columbia University, Micha el Shara of the AMNH, Jerry Bonnell of NASA and Astronomy Picture of the Day, Glennys Farrar of NYU and AlexWolszczan of Penn State. Two slots rema in to be filled. Further details will be in next months Eyepiece. Well also ha ve news of our autumn class next month. Member Stan Hondas photos of Manhattanhenge can be viewed in the galler y of our website, www.aaa.org. I was amused by the view of several people photographing the setting Sun with their cell phones. On August 5-7, the Escape 2 New Yor k Music Festival will occur in Southa mpton, N. Y. ( www. escape2ny.com). The festival seeks an astronomy-r elated perfor mance or demonstration, which could be telescopic viewing. Camp Simcha near Port Jervis is a camp for youngster s with cancer or other hematologic illnesses. This year weve been invited to bring telescopes to join them Sunday evening, August 7. If youd like to participate, call me. More observing sites and dates, some old, some new: September 3, October 1, November 5: Gateway Park, near Gil Hodges Bridge, Queens; Saturday, October 22: Urban Starfest at the Central Park Sheep Mea dow (rain date October 23). Jupiter will be near opposition; November 12: Fort Greene Park, Brooklyn; December 3: Avenue U Salt Marsh, Marine Park, Brooklyn. Info: www.aaa.org. If your e not on line but want to attend a session, call me. If you ima ge celestial objects and feed the output into a monitor for simultaneous viewing by several people, let me know. Wed like to set it up for Starfest and other obser ving sessions. Rich Rosenberg, president@aaa.org, (718) 522-5014 Legislators continued from page 1 to emer ge from Senate committee. The one time it emerged from both cha mbers, it was vetoed by Gov. Geor ge E. Pataki. This year's bills, like earlier ones, would have prohibited state agencies and public corporations from installing new or replacement per manent outdoor lighting unless such fixtures with output greater than 1,800 lumens are fully shielded. Ther e wer e several exceptions. Marcellino and Rosenthal aides agreed the main stumbling block was perceived cost. "In an age of austerity, the cost to the state and loca lities of compliance...was viewed as prohibitive," said Debbie Peck-Kelleher, Marcellinos investigation committee dir ector. Lauren Schuster, Rosenthals chief of staff, said the state doesnt want to strap localities with added costs. "I dont understand why people dont take this mor e seriously. State and local governments are gunshy since they perceive the upfront costs as high. Its hard to convince them of longter m cost savings." In an attempt to get something passed, Marcellino and Rosentha l introduced bills drawn from sections of the main bill. But these barely fared better than the primary legislation. The only success was a bill that will requir e the environmental conservation commissioner, in consultation with the ener gy research and development authority, to develop lighting efficiency standards. Bills that didnt make it included one that would ha ve directed the secretary of state to prepare and distribute to municipalities a model compr ehensive lighting or dinance. Another would have enunciated state policy on Legislators continued on page 10
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World Science Festival Leads Us Through the Dark Universe
By Evan Schneider
Look up at the night sky. Marvel at the cosmos. Squint to see that soft fuzzy ima ge of the Andromeda Galaxy, a mer e 2.2 million light-years away. Gaze at a brilliant star cluster or the constant glow of the stellar disk of the Milky Way, 100,000 light-years in dia meter. So ma ny bright lights to explor e. Yet with all that light and all those objects, 96% of the universe is dark. On June 2, seven World Science Festival panelists discussed "The Dark Side of the Universe." Dr. Brian Greene, superstring theorist, and professor of physics and mathematics at Columbia, introduced the program, stating dark energy is causing space to expand. But befor e dark ener gy, 73% of the universe, can be addr essed, we need to acknowledge the pr esence of dark matter, the other 23%. "Where do we find dark matter?" asked panelist Glennys Farrar, professor of physics at NYU. "It all began in 1930 with Swiss astronomer Fritz Zwicky, when he observed some galaxies wer e spinning so fast that stars should fly away from them--but they did not." In the 1950s, astronomer and physicist Vera Rubin measur ed light from multiple galaxies and applied the Doppler effect--obser ving the wa velength shift proportional to the speed of the light source relative to the observer. The data allowed her to calculate orbital speeds of stars in differ ent parts of those galaxies. Because stars in outer areas of the galaxies wer e moving as fast as the stars at the center, some unseen mass had to be causing them to move faster than anticipated. This is a dir ect gravitational effect of mass from dark matter. Dr. Katherine Freese, professor of physics at the University of Michigan, provided another key to locating dark matter: lensing, wher e mass bends light, creating multiple ima ges of a single object. These phenomena imply the presence of dark matter, but what if we could develop a detection system? Columbia physics professor Dr. Elena Aprile, founder of the Xenon Dark Matter experiment in Italy, is working on detecting wea k interacting mass particles (WIMPS)
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one mile under ground, to lessen background noise. The detector waits for ener gy to be released from cosmicwind radiation, exciting the xenon atoms. Its detected b y p h o t o mu l t i p l i e r s ( ht t p : / / w w w . p h y s o r g. c o m/ news/2011-04-dar k-closer-elusive-particle. html). This research may measure and identify dark matter. The relationship of dark matter (an attractive force) and dark ener gy (a repulsive force) may have played a major role at the time of the Big Bang. Dark matter plays a role in the development of accretion disks, pulling in electrons and protons to for m galaxies, while dark energy has been credited with expansion of the universe. The James Webb Space Telescope, designed to study for mation of early stars and galaxies thr ough infrared observations, may provide answers, Freese said. Dark-energy experts then took the spotlight, with Greene stating, "Galaxies rushing away from us should slow down over time." But Dr. Saul Perlmutter, a UCal/ Berkeley physics professor and astrophysicist who cha rts the expansion history of the universe, noted the universe is expanding faster and dark ener gy is pushing it. Perlmutter looked at thousands of ga laxies to find exploding supernova e. By measuring brightness of a supernova from pre- to post-supernova phases, distance and time of explosion can be deter mined. Using this as a gauge, the rate of universal expansion can be calculated. Theoretical cosmologist Dr. Micha el Turner, professor at the Enrico F er mi Institute, explained that dark ener gy is repulsive gravity, pushing the universe apart on a large scale while nor mal gravity pulls matter together on a smaller scale. Turners written perspective, "Dark Energy and the New Cosmology," is at . http:// supernova.lbl. gov/~evlinder/turner.pdf The panel was asked when dark ener gy and dark matter would be fully understood. Answers ranged from 10 to 15 years. Its debatable whether current theories and detection equipment will fuse to provide answers. Perlmutter would like to see Webb telescope data, as it will be positioned 930,000 miles from Earth. At that distance, the early universe should be easier to obser ve.


Dark Matter Arguably the Greatest Problem in Physics
By Alan Rude
Dark matter is arguably the gr eatest problem in physics, astrophysicists on a June 3 panel the World Science Festival agr eed. Panelists discussed efforts to detect this elusive and mysterious matter, which is inferr ed to exist from gravitational effects on visible matter, but is undetectable by electroma gnetic radiation and is non-baryonic--i. e., not for med of atoms. P:resent calculations indicate matter comprises 23% of the mass-energy of the universe. Dr. Glennys Farrar, professor of physics at NYU, discussed the lea ding contender for dark matter, supersymmetry. Supersymmetry, whimsically nicknamed S USY, is a pillar of string theory which posits that for every standard particle (e. g., quarks, photons, neutrinos), ther e are corresponding superpartner (SUSY) particles (photinos, squarks, neutralinos). These differ from standard particles by one-half unit of spin. The neutralino, a wea kly interactive massive particle (WIMP), has been regarded as a top candidate for a dark-matter constituent. . One particularly controversial experiment is known as DAMA, beneath the Italia n mountain of Gran Sasso. DAMA researchers have claimed to detect an annual fluctuation of dark-matter particles as the Earth moves through the dark-matter galactic halo. Subsequent experiments, including the experiment "Xenon 100" organized by panelist Elena Aprile, professor of physics at Columbia, havent been able to corroborate DAMA findings and have detected no WIMPs. However, in a recent development, researchers working on a dark-matter experiment half a mile under ground in a Minnesota mine claim theyve seen seasonally varying blips in electrical pulses that may be the telltale signs of WIMPs. One of the primary missions of the CERN Large Hadron Collider (LHC) is detection of SUSY particles, including WIMPs, which would be the ma jor breakthrough in dark-matter research. No doubt because of the promise of the LHC, several panelists were emphatic that the myster y of dark matter will be solved in this decade. Other astrophysicists, unconvinced with results of SUSY/WIMP research, have proposed an alternative in the for m of inter mediate-size black holes. Katherine Freese, professor of physics at the University of Michigan, stated they would ha ve been for med at the beginning of the universe--not later from collapsing supernova e--and ma y have masses ranging from several stellar masses to masses less than Jupiters. Priyamvada Natarajan, professor of astronomy physics at Yale, called black holes too small to be tected at great distances, but too large to evaporate du Hawking radiation, so theyve been able to survive almost the entire life of the universe. Q&A included these (paraphrased) highlights: Q: Is ther e dark matter in other, parallel universes? A: We can only theorize about alternate universes, but certain movements of galactic clusters indicate there might be gravity sources outside our universe, indicating dark matter. Q: Is dark matter affected by gravity? A: Yes, thats how it was detected in the first place. Q: Has the F ermi Ga mma-ray Telescope provided early insights into the nature of dark matter? A: Not yet, but ther es hope. and dee to for

Ferris Helps Sungazers
By Anne Kiefer
As part of the World Science Festival, amateur astronomers gathered on Governors Island June 4 to explore the science of sungazing and listen to a talk on the subject by writer and scientist Dr. Timothy Ferris. Six stations of specially outfitted telescopes wer e set up to study solar weather patterns. Amateurs manning the telescopes explained the two ways one could outfit a Sungazers continued on page 10
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Review: A Professor, A President and A Meteor
By Dan Harrison
On December 14, 1807, a meteorite fell to the ground in Weston, Conn. Within da ys, a 28-year-old la wyerscientist na med Benja min Sillima n, who had become Yales first professor of chemistry five years earlier, was on the scene. By the end of the month, he published an account of the meteorite in Connecticut Herald. Neither Sillima n nor anyone else knew it, but by scouring the town for data, "he diligently sowed the scene for what scientists know toda y regarding the big ba ng theory, the for mation of Earth, and other planetary bodies," says Cathryn J. Prince in "A Professor, A President, and A Meteor" (Prometheus, $26). "Indeed, the Weston Fall was a turning point for Amer ica n science and for Amer ica. The young nation could now occupy a seat at the table with the gr eat Europea n thinkers." The president in the book's title is Thomas Jefferson, who in late 1807 was in the home str etch of his tenure. Jefferson was devoted to science, but not all sciences. He had little interest in astronomy or geology, believing botany and chemistry could be harnessed for practical use in ways that geology and astronomy could not. "...most scientists...consider ed...meteors and fir eballs unrelated to mor e legitimate astronomical events such as asteroids and comets. It took mor e than two centuries...before scientists concluded that these occurrences are related." To ma ke matters mor e complicated, Sillima ns achievement in proving that meteors had cosmic rather than terrestrial origins, and that they wer ent ejecta from lunar volca noes, beca me enmeshed in the politics of the day, when New England Federalists and southern Republican-Democrats bitterly opposed each other. Silliman bent over backwards to steer clear of politics, Prince writes, especially since ma ny Federalists assailed Jeffersons devotion to science. Sillima n also sought to balance his r eligion with his pursuit of science. "The meteorite truly presented a once-in-a-lifetime opportunity...He understood that an event of this magnitude requir ed careful analysis."
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More specifically, Sillima n was the first scientist to interview witnesses and personally analyze stones that composed a meteorite. He conducted ma ny experiments to identify the meteorites composition. Nearly spherical chondrules wer e seen as proof that the Weston meteor "hailed fr om the great beyond...Later scientists would deter mine that [it] likely began its journey to Earth some thirty million years after two asteroids collided. The collision produced thousands of rocky bodies, further crowding the asteroid belt between Mars and Jupiter." Silliman's chemical report snared the public imagination, Prince says. "It was the first step toward thoughtful popularization of science...His endeavor offers rare insight into the state of American science as it stood on the cusp of a new international identity." The report "laid the foundation for the the future study of meteorites. Everything scientists know today about meteor ites--the different types, the various minerals, trace elements, and isotopes contained within--bega n in Sillima ns laboratory." "Throughout his tenure at Yale," Prince notes, "Sillima n never ceased thinking about the immensity of space. He never tired of watching the winking lights of the night sky, regarding stars as the gatekeepers to other planetary systems outside our own." This book is a good read, especially if your e a history buff. Prince puts scientific events into political, social and religious context, in fewer than 200 pages. She also does something relatively few historians have done: shine a spotlight on part of the period between the Revolution and the Civil War, decades which, except for such figures as Andr ew Jackson, Daniel Webster and John Brown, remain generally unmined.

Contacting the AAA
General club matters: president@aaa.org. Membership business, such as dues and change of addr ess: members@aaa.org. Eyepiece: editor@aaa.org. Lectures: lectures@aaa.org. Classes: classes@aaa.org. Seminar: seminar@aaa.org. Observing: president@aaa.org. Please visit us on the web at www.aaa.org.


Briefs: Congressional Budget Cutters Want to Ax Webb
Astronomers are up in arms over proposed congressional budget cuts that would cancel the James Webb Space Telescope (JWST). The House Appropriations commerce, justice and science subcommittee, which oversees NASA, proposed a 2012 spending bill last month that would ter minate the JWST as part of wider reaching cutbacks that would reset the a gencys budget at pre-2008 levels. "JWST will la y the foundation on which a better understanding of the early universe will be built," Debra Elmegr een, president of the Amer ican Astronomical Society (AAS), said. "It has the potential to transfor m astronomy even more than the Hubble Space Telescope did." In a statement, AAS members ter med the JWST critical to helping astronomers better understand the earliest for mation of stars and planets, and said its operation will shed light on complex mysteries of the universe. The $6.5 billion JWST is an infrared observatory designed to peer farther back into the universes history than ever befor e, exploring deep-space phenomena from distant galaxies to planets and stars. Under the proposal announced July 6, NASA would receive $16.8 billion in funding, $1.6 billion less than last year and $1.9 billion below President Oba mas 2012 request. The subcommittee described the JWST as being plagued by cost overruns and poor management. Its construction has faced budgetary woes and dela ys. A panel investigation last year found the project had overrun its cost by $1.5 billion, and bla med the troubles largely on misma nagement. Most recently, a reva mped budget and technology plan estimated that JWST could launch by 2018. In the wake of the proposed cancellation, NAS A deputy administrator Lori Garver spoke about the value of the JWST: "This is a perfect exa mple of NASA revealing the unknown a nd r eaching for new heights. Well be prepared to lay out a budget that will allow us to launch the JWST in this decade, within the next budget cycle." The draft $16.8 billion figure includes $1.95 billion for the Space Launch System, the hea vy-lift rocket Congress order ed NASA to build for deep-space exploration. The proposed 2012 funding is $150 million mor e than the lifter got for 2011, but some $700 million below the a mount recommended in the NASA Authorization Act of 2010, which beca me law in October. An unmanned NASA probe ma de history 117 million miles fr om Earth July 16 when it arrived at the huge asteroid Vesta, making it the first spacecraft to orbit an object in the solar systems asteroid belt. The Dawn spacecraft enter ed orbit around Vesta after a four -year trip and will spend about a year studying the 330-milewide rock befor e moving on to visit the dwarf planet Ceres in 2015. Vesta, the brightest asteroid in the solar system, is about the size of Arizona. Its in the asteroid belt between the orbits of Mars and Jupiter. The earliest black holes seem to be hiding behind thick clouds of dust and gas, a new study finds. Astronomers have long searched for black holes at the center of some of the first known galaxies, with no results. The study has not only pinpointed these objects, its determined theyre closely tied to evolution of their galaxies. As particles speed up, they emit massive ener gy. Galaxies that formed only 1 billion years or so after the Big Bang dont seem to have such outbursts, leading scientists to conclude their black holes wer e smaller. Early black holes wer e hard to locate because they were shrouded in dense dust of their galaxies. Not only did the tea m find early giants, they discover ed the first supermassive black holes wer e closely related to their galaxies. The mass of the black holes, for instance, correlates to the luminosity of the galaxy, and to the mass of the dark matter halo surrounding it. Early black holes wer ent expected to have this connection. A powerful beam of energy has been spotted blasting from the center of a massive black hole as it rips apart and devours a star in a rare sight astronomers believe happens only every 100 million years. Astronomers initially thought it was a powerful burst of ga mma rays from a collapsing star. But when the ener gy was still seen months later, they r ealized something mor e mysterious was going on. That its fading ver y slowly shows this isnt an ordinary ga mma-ray burst. The ga mma-ray flash is in the constellation Draco, at the center of a galaxy nearly 4 billion light-years away. Effects of a ga mma -ray burst typically can be obser ved for only about a day. The highly energetic and long-lasting X-rays and ga mma -rays wer e produced as a star about the size of our Sun was shredded by a black hole 1 million times mor e massive. This a rare event because the black hole hasnt been eating up matter around it like some other active black holes. Continued on page 8
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Briefs: MESSENGER Begins Unlocking Mercury's Mysteries
Continued from page 7 Astronomers have long suspected that galaxies grow large due to an insatiable appetite for interstellar gas, but a new study suggests they may slowly graze on it. Galaxies in the distant universe continuously ingested their star -making fuel over long periods of time, says the study, which used Spitzer. New evidence shows galaxy growth in which a typical galaxy fed itself through a steady stream of gas, making stars much faster than thought. Astronomers have long wonder ed wher e distant galaxies acquir ed this stellar fuel. The most favor ed theor y was that galaxies gr ew by mer ging with other galaxies, feeding off gas stirred up in the collisions. Scientists surveyed mor e than 70 remote galaxies that existed 1 billion -2 billion years after the Big Bang. Previous studies using ultraviolet-light telescopes found much less star for mation than Spitzer, which sees infrared light. Observations from the orbiting MESSENGER mission to Mercury could help unlock mysteries. Some pictures have revealed huge expanses of volcanic deposits near the north pole. Observations help confir m volcanism has substantially shaped Mercurys crust and surface for much of its history. MESSENGERs X-ray spectrometer detected surprisingly high levels of sulfur at the surface, which could help explain Mercurys origin and volcanism. Obser vations revea l Mercury isnt similar to the Moon or other terrestrial planets. MESSENGER will gauge whether Mercury harbors water ice on its surface. That might seem unlikely, since average surface temps can top 800 degr ees. However, Earth-based radar observations 20 years ago suggested large amounts of ice may lurk in per manently shadowed craters at the poles. Early results from MESSENGER support the idea. Data indicate some polar craters may be so deep their floors are in per manent shadow. Scientists also hope to learn why Mercury is much denser than other rocky planets. Humongous waves of hot plasma on the surface of the Sun appear to be moving as fast as 4.5 million mph. The wa ves are so huge it would take up to 16 Earths, end -to-end, to match them. Its the first evidence the Suns lower atmospher e contains such waves. They have periods of 30-200 seconds and wavelengths of 62,000124,000 miles. Solar waves are produced when a flare or eruption on the surface kicks up hot plasma. Scientists
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have observed slow-moving waves on the Sun, but fastmoving waves, also pr edicted by theory, ha d gone undetected because previous telescopes couldnt take pictures fast enough to image them. Astronomers have seen about a dozen such wa ves. Theyre believed to be responsible for many fundamenta l, yet enigmatic processes, such as heating the corona to millions of degr ees, accelerating the solar wind, triggering remote eru