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Journal of the Amateur Astrono mers Association of New York December 2011 Volume 59 Number 12 ISSN 0146 -7662 MESSENGER BRIEFING: ORBITING the METAL -RICH PLANET
By Denton Ebel, Curator (Meteorites) Curator-in-Charge Dept. of Earth and Planetary Sciences, AMNH
MESSENGER stands for Mercury Surface, Space Environment, Geochemistry, and Ranging. This instrument -rich spacecraft, launched in August 2004, is designed to answer a broad range of science questions. Eyepiece readers may have attended the public lecture given by Principal Investigator Sean Solomon of the Carnegie Institution of Washington in July 2010 at the American Museum of Natural History. After three fl ybys, a major rocket burn inserted the MESSENGER spacecraft into Mercury orbit six months ago. What have we learned? Seven papers in Science (vol. 333, 30-Sept-2011) reveal Mercury's surface composition, map flood volcanism in the Northern Plains, suggest possible recent volcanic activity, constrain the shape and variability of Mercury's magnetic field, and describe interactions bet ween the magnetosphere and plasma in Mercury's exosphere. "This is the first major scientific meeting at which MESSENGER orbital observations are being presented to the scientific community," sa ys MESSENGER Principal Investigator Sean Solomon of the Carnegie Institution of Washington. "As the first spacecraft to orbit our solar system's innermost planet, MESSENGER continues to reveal new surprises every week. It is timely to sum up what we've learned so far and to seek feedback from our international colleagues across planetary science on our interpretations to date." The composition of Mercury is ver y different from that of the Moon and other terrestrial planets. Its iron core makes up about 65 % of Mercury's total mass. Earths core, by comparison, is just 32 % of its mass. Understanding how such a planet accumulated from the dust, ice, and gas in the earl y solar nebula is a key science goal of the MESSENGER mission. To a cosmochemist, the finding of an Earthlike ratio of potassium to thorium, very unlike the low ratio in the Kdepleted Moon, signifies lack of substantial fractionation of volatile elements. Mercury's surface also has a high sulfur/ silicon ratio, higher than the Earth's. Both of these findings rule out formation hypotheses requiring the boiling off of Mercury's mantle by an early, hot sun, or high -temperature condensation of Mercury from the same kind of material that formed the Earth. MESSENGERs compositional analysis also raises difficulties for another hypothesis: that a major impact occurred

EYEPIECE
after differentiation of the core, and stripped off much of the planets original mantle. Re-accreted impact debris should have lost volatile elements to space. Unless almost all of the stripped mantle material failed to re-accrete, Mercury's high volatile content is difficult to explain by the impact hypothesis. Your author, and Conel Alexander of the Department of Terrestrial Magnetism at the Carnegie Institution of Washington, recently proposed in Planetary and Space Science that Mercury's formation zone was enriched in carbon -rich interplanetary dust that caused sulfur to condense into solid, less volatile minerals at very high temperatures. This hypothesis predicts MESSENGERs findings of high sulfur content, but does not entirely explain the stark condition of Mercury's huge iron core. New research results are expected to come from recent increases in solar flare activity excited x-ray emission by heavier elements, allowing further confirmation of Mercury's high sulfur/silicon ratio by the MESSENGER x-ray fluorescence spectrometer (XRS), and better constraints on surface concentrations of titanium. Accumulating XRS data begin to suggest compositional differences bet ween various rock units.. Spectroscopists are working to tease out the mineralogy of Mercury's surface, but its low iron and titanium contents relative to the Moon or Mars render infrared spectra nearly featureless. Measurements of Mercury's elongate scarps are providing new constraints on how much the planet has shrunk over time. The geoph ysics group has worked out the parameters that describe Mercury's shape, using gravity data (ranging). These constrain models of Mercury's interior structure, which is sure to be unique given its large core and sulfur-rich composition. With time, the complex exosphere - magnetosphere - solar wind interactions begin to reveal themselves as solar maximum is approached. MESSENGER has provided the first up-close look at Mercury since the Mariner flybys of the 1970's, and the first sustained investigation from orbit. Humans have been trying to figure out how planets form for hundreds of years, and these new findings bring the last so-called 'terrestrial planet' into the realm where comparative planetology can be applied with strong observational constraints.


EYEPIECE

December 2011

WHAT'S UP IN THE SKY
AAA Observer's Guide for December 2011 By Richard Rosenberg

AAA LECTURE SERIES TO PRESENT NOVAE and SUPERNOVAE - DEC. 2
By Dan Harrison Dr. Michael Shara, curator in the Department of Astrophysics at AMNH, will discuss "How Novae and Supernovae Are Connected" on Friday, December 2. The free public lecture begins at 6:15 p.m. in the Kaufmann Theater . In discussing what hell talk about and why its significant, Shara tells Eyepiece: "The 2011 Nobel Prize in physi cs was awarded to three astrophysicists credited with discovering ,,dark energy, the mysterious entity which accounts for 70% of all the mass-energy in the universe, and which is causing the universes expansion to accelerate." "Measuring and understanding dark energy hinges on understanding type Ia supernovae, the ,,standard candles used by the Nobel prize winners. Are these luminous objects reall y all the same luminosity, or do they have subtle differences whose misinterpretation could mimic an acceleration of the universe? The only wa y to understand type Ia supernovae is to know, with certainty, exactly what kind of star gives rise to them. This would allow astronomers to determine if these kinds of stars changed systematically over 13 billion years, and thus if we might be misinterpreting them as standard candles when they are, in fact, not standard at all. Six models for type Ia-supernova progenitors, the stars that give rise to them, have been proposed in the past 30 years, including several kinds of novae. Ill describe these models, and show how Hubble Telescope observations have made dramatic progress in the past six months in ruling out all but two of these models. Ill also answer the question: Could dark energy not really be there?" Prior to joining the museum 12 years ago, Shara spent 17 years at the Space Telescope Science Institute (STSI) where he managed peer-review committees for the Hubble and is now an astronomer with tenure. His Ph.D. from Tel -Aviv University and masters degree from the University of Toronto are augmented by an adjunct professorship at Columbia. Sharas AMNH responsibilities are to conduct research, train astrophysicists, and curate exhibitions. His "Beyond Planet Earth" special exhibition opened Novem ber 19. Sharas research interests include the structure and evolution of novae and supernovae, collisions between stars and the remnant descendants of those collisions, and the populations of stars inhabiting star clusters and galaxies. Future AAA 2012 Lecture Series Dates
January 6: Robert Nemiroff, Michigan Technological University and NASA, "Best Short Astronomy Videos" February 10: Glennys Farrar, NYU, "Getting Photos of Supermassive Black Holes Tearing Stars Apart" March 2: Charles Keeton, Rutgers, "A Ray of Light in a Sea of Dark (Matter)" April 6: Debra Fischer, Yale, "Searching for Earthlike Worlds" May 4: Alex Wolszczan, Penn State, " The Astronomical Future of Man."
For more information, go to: www.aaa.org/lectures1112

December's Evening Planets: At dusk, brilliant Venus
is low in the southwest, slowl y getting higher each day. After Venus sets, Jupiter dominates the sky. The Moon passes close to Jupiter on the December 6 and meets Venus as a lovel y crescent on the December 26.

December's Evening Stars: Here come the magnificent
winter stars! By 6 p.m., in the middle of December, Auriga and Taurus (with its Pleiades and Hyades clusters) are up in the east. An hour later Gemini and Orion join them, followed by Canis Minor and Canis Major with the brilliant star Sirius.

December's Morning Planets: At 11 p.m. Mars rises.
If you can, watch it regularly ­ you will see the Red Pl brighten with each month. Around 3 AM Saturn comes Before dawn you will be able to spot Mercury easily in southeast. It will be best on the Decem ber 23, but still be ily seen a week before or after. a.m. to see the tail end of the Gemini, Canis Minor and parts spring stars are at center stage: Spica in Virgo (Saturn nearby), anet up. the eas-

December's Morning Stars: Look to the west about 6
winter constellations ­ Auriga, of Orion and Canis Major. The Regulus in Leo (Mars nearby); and Arcturus in BoЖtes.

Comet Garradd: In Hercules this month, it should be visible with binoculars. Look for it in the northwest in the earl y evening hours or in the east just before dawn breaks.

December Day-by-Day
December 2 ­ First Quarter Moon at 4:52 a.m. December 4 ­ Mercury at inferior conjunction, entering the morning sky December 6 ­ Jupiter is upper left of the Moon this evening December 10 ­ Full Moon at 9:36 a.m. Total lunar eclipse is visible onl y in the western US December 10 ­ Uranus is stationary, resuming direct eastward motion with respect to the stars December 14 ­ The Geminid meteor shower peaks December 17 ­ Mars is well north of the Moon December 17 ­ Last Quarter Moon at 7:48 p.m. December 20 ­ Saturn is north of the Moon this morning. December 22 ­ Winter begins at 12:30 a.m. EST December 23 ­ Mercury is at its greatest western elongation in the morning sky December 24 ­ New Moon at 1:06 p.m. December 26 ­ Jupiter is stationary, resuming eastward movement with respect to the stars December 26 ­ Venus is left of the crescent Moon December 29 ­ Pluto is in conjunction with the Sun December 31 ­ Minor planet Ceres is in conjunction with the Sun
For more information go to: http://www.aaa.org/month1112

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EYEPIECE

December 2011

A Message from AAA President Richard Rosenberg
Hello Members: Its getting a little chilly, but were rewarded this time of year with a bunch of easy to spot constellations, magnificent s tar clusters (including the Pleiades), a nebula visible with binoculars (the Orion Nebula), the remains of a supernova explosion (M1) and most exciting -- a comet bonus (comet Garradd). Comet Garradd is predicted to be sixth -magnitude in brightness through February, making it visible in a telescope and binoculars. Now in the constellation Hercules, it is positioned in the northwest a short time after sunset and a short time in t he east before sunrise. Early in December is the best time to see it in the evening -- visibility diminishes with each week , and it is lost in twilight by the end of the month. To compensate, the comet becomes more easily visible in the pre -dawn sky throughout winter. On Saturday December 3, well have a good chance to spot the comet and other objects at the Salt Marsh Nature Center from 5 p.m. to 8 p.m. Observing will be preceded by a talk describing the winter sky. For more information and driving instruction s, go to http://www.aaa.org/saltmarsh on our website. Later in the month, from 5 p.m. to 7 p.m. on Wednesday, December 21, well have another observing session at Belvedere Castle in Central Park. Comet Garradd will probabl y not be visible but the winter sky will be spectacular and Venus, Jupiter and the Moon will compensate. There will also be a pre-event talk. In addition to these two special events, there will be observi ng at Floyd Bennett Field on Dec 2 and solar observing in Central Park on Dec 17. Our monthly seminar series in conjunction with New York University continues on December 8. Event chair and NYU professor Gerceida Jones will speak on The Sirius Mystery by Robert K.G. Temple (St. Martins Press, 1975). It presents the hypothesis that the a west African tribe preserves a tradition of contact with intelligent extraterrestrial beings from the Sirius s tar-system. This months lecture will be given by Michael Shara of the AMNH. He will speak Dec 2 on "How Novae and Supernovae are Connected." We hope to see many of you at a AAA event soon.

Sincer ely,

Rich Rosenberg, AAA President, president@aaa.org (718) 522-5014

GOOD COMETS DON'T DIE ... THEY JUST FADE AWAY
Russian amateur astronomer Leonid Elenin had the good fortune to discover a comet last December 10, but it lasted less than a year from then until its demise. Initially, comet Elenin received much attention because its orbit would take it close to Earth, within 22 million miles on October 16. As recently as August 19, the comet was brighter than predicted, as observed by amateur astronomers in Australia, notably Michael Mattiazzo. Then a coronal mass ejection made the comet drop half a magnitude in brightness. It continued to drop, despite getting closer to the Sun. Elenin was apparently disintegrating, as can happen when comets pass too close to the Sun. On September 10, the comet passed its perihelion, marking its closest approach to the Sun at 44.84 million miles. The next day, Mattiazzo managed a couple of images in evening twilight as Elenin dropped too cl ose to the Sun to be followed any further. The comet was a faint ghost of its former self. Elenin passed Mercury September 27 before moving out of SOHOs field of view September 29. The comet, whose remains wont return for 12,000 years, came closest to Earth October 16, but by that time all that was left were small bits. When it passed perihelion in September, it

had broken into pieces. When Elenin came within 22 million miles of Earth, only a cl oud of debris was visible in scopes. The comet had been 1.2 miles wide when it was in one piece. CALL FOR EYEPIECE WRITERS Those members who enjoy reading Eyepiece may want to learn more about astronomy by participating as a writer. For the past two years and now as current editor, I am constantly exploring leading-edge astronomical events through research for my articles and attending lectures and presentations as an Eyepiece representative. I encourage anyone focused on learning more about the science of astronomy and the exciting missions at NASA, ESA and other sources in the field to join our team of dedicated writers. Please contact me directly to discuss working together.

Evan B. Schneider, Editor
Email: editor@aaa.org Tel: 212-986-4225 Contacting AAA: Website: www.aaa.org; General Club Matters and Observing: president@aaa.org; Membership Business: members@aaa.org; Classes: classes@aaa.org; Seminars: seminar@aaa.org; Eyepiece: editor@aaa.org 3


EYEPIECE

December 2011

AMNH LAUNCHES ITS VISION - THE FUTURE OF SPACE TRAVEL By Dan Harrison
AMNH astrophysicist Michael Shara, lead curator for "Beyond Planet Earth: The Future of Space Exploration," an exhibition at the museum that opened November 19 and runs through August 12, 2012, told a media preview November 15 that the exhibition is coming at a critical time for NASA. "Were at a kind of crossroads. The shuttle program has ended, and thats a little bit like graduating from kindergarten. We want to take those next steps out of our backyard into the neighborhood and then into the big cit y to visit all the other places in the solar system." The show offers a vision of the future of space travel as it explores our next steps in the solar system and beyond. It takes visitors on humanitys journey t o explore the next frontier, either through ourselves or via robotic proxies. Highlighted conceptual future missions include building a space elevator on the surface of the Moon, deflecting a hazardous near-Earth asteroid and traveling to Mars--perhaps establishing colonies there. Before attending the exhibition, visitors can download a free augmented reality (AR) app for iPhone, iPod Touch or iPad created for the show. The app, "Beyond Planet Earth Augmented Reality," can activate 11 AR icons throughout the exhibition, which unlock animations and allow visitors to share images via e-mail, Facebook and Twitter in addition to accessing a special site with additional space-themed links. The icons and links can also be found on the "Beyond Planet Earth" section of amnh.org. The exhibition opens with a retrospective of historic manned and unmanned space missions: Sputnik 1, the first manmade satellite; the Vostok 1 space capsule that boosted Yuri Gagarin, the first man in space, into orbit; the Hubble Space Telescope; and a Mars Exploration Rover. Authentic equipment and artifacts on display include a Soviet cosmonaut helmet and U.S. astronaut gloves. A model of Virgin Galactics SpaceShipTwo, a space plane in development, highlights emerging space-travel vehicles. The solar system theater has a video presentation that introduces visitors to future manned and unmanned space missions to Mars, Europa and beyond. The section on returning to the Moon notes that NASA and other space agencies have identified Shackleton Crater, near the South Pole, as a promising site for a lunar base because it offers access to resources such as water -ice and nearconstant sunlight to generate electricity. Along with a scale model of a habitat that could house four astronauts, this area features models of a space elevator that could transport mined materials and a liquid-mirror telescope on the Moons surface. Exploring Asteroids: This section features a 3-D recreation of the near -Earth asteroid Itokawa and the Japanese Ha ya busa spacecraft that rendezvoused with it in 2005 to collect samples. Obtaining pristine samples for study not onl y helps scientists better understand the formation of the solar system, but may reveal the presence of valuable metals. Iron 4 meteorites like the Knowles meteorite from the museums collection are 99% metal alloy and, like some asteroids, could be mined for valuable materials. Asteroids are also a constant threat to life on Earth. NASA has identified more than 1,200 asteroids wider than 500 feet whose orbits come within 5 million miles of Earth. A touch-screen interactive exhibit explores plausible scenarios for deflecting a "doomsda y" asteroid. Next comes Mars. Theres a full-scale model of the ninefoot-long Mars Science Laboratory Rover, Curiosity, which launched from Cape Canaveral on November 26. It will seek evidence of organic life. Miniature models show how astronauts might eat, sleep and exercise during a months-long journey aboard NASAs Nautilus-X spaceship. Since not ever yone is suited for the trip, visitors can take a personality test to see how theyd fare. A prototype of a new space suit shows what an astronaut might wear. A walk-through diorama of the Martian surface and an interactive fl y-over simulation give visitors a sense of what it might be like to explore the planet. Visitors can zoom in on locations such as the Gale Crater, the landing spot for the Curiosit y Rover, and Olympus Mons, the largest volcano and tallest mountain in the solar system. The Mars terraforming table allows several visitors at once to transform Mars from a frozen, thin-aired environment to an Earth -like planet. The exhibit then moves t o the outer solar system. The search for life on Europa could fall to a robotic submersible, a prototype of which is featured, that would melt through the moons icy surface and explore its salty oceans. Now its time to exit the solar system. The exhibition concludes with a look at more than 1,000 stars that have been found to have planets. These exoplanets were detected by the Kepler Space Telescope in the first four months of operation. In conjunction with the show, the museum is offering lectures and educational programming. These include SpaceFest January 15, a family celebration featuring spacerelated activities, performances and special dome presentations. There will also be a March 11 program about extremophiles that will examine how organisms that survive in Earths most hostile environments offer clues about extraterrestrial life. See amnh.org for info on additional programs. Predictabl y, Shara and astronauts Mike Massimino and John Grunsfeld, who appeared on a panel at the media preview, asserted that benefits of space travel will be worth the expense. But it was clear they are cognizant of the challenge facing these far -reaching programs: pressure on all agencies of government, including NASA, to tangibl y pare budgets. That notwithstanding, the three agreed major advances can be expected starting in 10 years, with Shara predicting humans on Mars in 15-20 years. "Well only know a bout Martian life by going there," Shara said.


EYEPIECE

December 2011

EXPLOSIVE GAMMA-RAY BURSTS LIGHT UP THE UNIVERSE
By Alan Rude
What is the farthest one can see with the naked eye? This has long been a trick question posed to non -astronomers. When pointed to the Andromeda Galaxy, they were astonished to learn that they could see an object over two million light years awa y (if you do the math, that distance is an incredible 13,000 quadrillion miles). On March 19, 2008, astronomers detected a burst of energy which shattered the record for the most distant object ever discovered. A gamma-ray burst (GRB 080319B) was observed with a visual magnitude 5.3 at a distance of 7.5 billion light years, 3,700 times the distance to the Andromeda Galaxy. Half-wa y across the visible universe, the visual afterglow following the burst set a new record for the most intrinsicall y bright object ever observed: 2.5 million times brighter than the brightest supernova. This burst emitted more light and energy in several seconds than the Sun will emit over its entire lifetime. Gamma-ray bursts are, with the exception of the Big Bang itself, the brightest, most intense and most powerful explosions in the universe. GBR080319B (GRBs are designated by year [2008] month [03] and date [the 19th]), may have been the brightest of those observed, but all such objects emit amounts of energy greater than the Milky Wa y Galaxys output for an entire year. GRBs were first observed by the Vela system of satellites deployed to detect covert (i.e. Soviet) nuclear experiments. Vela detected emissions of gamma-rays and, after ruling out the Earth and Sun as possible sources, scientists concluded that these were "cosmic in origin". At first the common hypothesis was that these flashes or "bursts" originated from inside the Milky Wa y. Further GRB analyses showed that they were evenly distributed throughout the sky and not just in the plane of our galaxy. In fact, many of the newl y discovered GRBs were at "extra-galactic" distances, as far as 13 billion light years away. This discover y brought up a significant problem. At such distances and assuming a spherical pattern, the colossal energy output could not be explained by any known physics. In rethinking the problem, astronomers devel oped a "jet -beaming model" where the energy is concentrated in two particle jets flaring in opposite directions and expanding outward at relativistic speeds. Only when a GRB jet points directly at the Earth do we detect the full effect of the gamma-ray explosion and the visual afterglow. This jet-beaming model reduces the energy emitted to ranges that our physics can handle. GRBs have been studied intensivel y for almost four decades utilizing a series of observing satellites. The first, BATSE, was deployed in 1991. BATSE showed that the majority of gamma-ray bursts originate in distant galaxies and therefore are highly energetic. BATSE was followed in 1996 by BEPPO-SAX, a Dutch-Italian mission affording increased precision in observation utilizing a wide-field camera. In 2004 NASA launched the SWIFT Gamma-ray Burst Explorer. Six years later SWIFT had detected its 500th GRB, an impressive number which included the brightest burst (GRB 080319B) as well as the farthest burst and farthest object of an y kind ever sighted (GRB 090429B) 13.14 billion light years distant. Finally, the Fermi Gamma -Ray Telescope launched in 2008. Fermis most exciting discover y is GRB 080916C, a burst releasing the greatest amount of total energy ever recorded. This enormous output was due to the bursts 23minute duration compared to the two second average for short duration, high-energy GRBs. Astronomers now divide GRBs into two categories: long bursts exceeding two seconds and short bursts. Each type has its own characteristics. Each is powered by different physical phenomena. Scientists are now certain that long bursts, which account for about 70% of all GRBs, result from the collapse of massive stars into black holes. The gamma-ray emissions from long bursts tend to emit lower levels of energy while long bursts are linked to supernovae. However these supernovae are special; only one in 1,000 are powerful enough to generate the energy associated with a long gamma-ray burst. The longest lasting GRB was detect ed in March 2011 in the center of a galaxy 3.8 billion light years away in the constellation Draco. The burst lasted over a week and is believed to be the result of that galaxys massive black hole shredding a neighboring star. Because of their brief duration, short GRBs are still poorl y understood. There are no supernova remains after short bursts which eliminates a massive star collapse as a cause. A consensus is developing among astronomers that the short bursts are the result of extremely violent collisions bet ween neutron stars or even between neutron stars and black holes. To date, no gamma-ray bursts of any kind have been observed within our Milky Wa y Galaxy. How fortunate for us all. A burst occurring 10,000 light years away with its jet pointed in our direction would eliminate most life on Earth. There is some good news, though. In 2006 the Hubble Space Telescope determined that the composition of our galaxy is not favorable for spawning long duration GRBs; unfortunately, this is not the case for the short duration variety. We are still at risk, but at least Earth is a small target in a sea of stars. NEBULA OF THE MONTH--ORION A vast stellar nursery 1,500 light-years from Earth, the Orion Nebula has been studied recently by the Spitzer Space Telescope taking amazing infrared photographs of the evol ving mass of gas and forming stars. The brightest portion of the nebula is centered on Orion's young, massive, hot stars, known as the Trapezium Cluster. But Spitzer also detects the nebula's many protostars, still in the process of formation. Red spots along the dark dusty filament to the left of the bright cluster include the protostar cataloged as HOPS 68, recently found to have crystals of the silicate mineral olivine within its protostellar envelope. 5


EYEPIECE

December 2011

THIS MONTH'S BOOK REVIEW

Astronomical Facts of the Month

"A MORE PERFECT HEAVEN..."
By Luis Marcelo Cabrera "Fascinating and immersive" - that is how I describe Dava Sobel's latest book, "A More Perfect Heaven: How Copernicus Revolutionized The Cosmos" (Walker & Company, 2011, $25). Although the main ideas behind the Copernican model have been discussed, explained and debated for centuries, the author successfull y mixes science, history, biography and political affairs to bring a truly entertaining account of Copernicus and the publishing of De revolutionibu, his seminal work on heliocentric theory. The book is divided into several chapters comprised of three main parts. The first describes Copernicus' life, interests and work. It is a very fluid narrative, not spending too much time detailing the political arena of the times but still exploring several historic events that play a significant role later on the book. and in history. Sobel continues the story as if it were a play, narrating the relationship between Copernicus, Rethicus and other characters. Although no one knows for sure how he managed to convince his master to publish De revolutionibus the young mathematician Rethicus ultimately succeeds. Sobel's prose is a compelling presentation of the event. The book paints a vivid picture of the dangers awaiting anybody who opposes clerical teachings, scripture and common sense. Not only the Roman Catholic Church would later condemn heliocentrism, but prominent protestant figures, including Luther himself will voice strong opposition to this concept. The book continues with a collection of accounts about the "aftermath" of the publication of De revolutionibus, providing descriptions of the works of renowned scientific masters Rethicus, Tycho, Kepler, Galileo and others, and how each scientist was influenced by Copernican theory. These scientists were all linked by their common goal to seek out the truth, and at the time Copernicus perspective was the strongest. Sobel graciously describes in great detail personal experiences surrounding the publication of De revolutionibus. Fascinating anecdotes include "Doctor Copernicus" and his work as a canon of the Archdiocese of Varmia, Rethicus' stay in Varmia during times when Protestants had been vanished from that land and life before and after working with Copernicus. Of particular interest is the anonymous and unauthorized preface to De revolutionibus by Osiander and Kepler's later attack on Osiander when he published his New Astronomy. Fascinating read, entertaining and informative, "A More Perfect Heaven" is another great work by this accomplished author. Science buffs and history l overs alike will enjoy reading the chronicles of a Polish cleric, his secret manuscript and how its publication revolutionized the way we understand our place in the universe today. As she achieved with her previous international bestsellers "Longitude and Galileo's Daughter, " Sobel pushes beyond popular science writing into a book that is entertaining and intriguing for us all. 6

What Color is the Universe? The answer is "pinky beige" according to John Hopkins University and the Australian 2dF Galaxy Redshift Survey at the Anglo-Australian Observatory in New South Wales, Australia. Perception of color will vary depending upon viewi ng at setting daylight (Standard D65) or when dark adapted (Illuminant E). ________________________ How Did It Get to be This Color and Will It Change? The universe started out young and blue, and grew gradually redder as the population of evol ved red giant stars built up. The rate of formation of new stars has declined precipitously in the last 6 billion years due to the decline in reserves of interstellar gas for forming new stars. As the star formation rate continues to decline and more stars become red giants the color of the universe will become redder and redder. Eventually all stars will disappear and nothing will be left but black holes. These too will eventually evaporate via the Ha wking Process and nothing will be left except for old light, which will itself redden as the universe expands forever (in the current cosmological model).

NOVEMBER OBSERVATIONS By Joseph A. Fedrick
Venus Enters the Evening Sky A Large Sunspot Region (1339) Appears During the first two weeks of November I watched the Sun become more active as I projected its image using my 60mm refractor scope. During November much of the Sun was covered with spots and an especially large group, numbered as Region 1339 by solar astronomers, was so large that it was visible with eclipse glasses without magnification. I have not observed any Northern Lights yet; however, several nights