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EYEPIECE
Journal of the Amateur Astronomers Association of New York February 2009 Volume 57, Number 2, ISSN 0146-7662

`100 Hours of Astronomy' Effort Is Ready to Roll
By Jason Kendall
On January 6 in Long Beach, Calif., the American Astronomical Society kicked off the beginning of the International Year of Astronomy 2009 with a big celebration attended by hundreds of professional and amateur astronomers. I was there, presenting a paper on my efforts at public outreach during this important year for astronomy worldwide. This year is the 400th anniversary of Galileo publishing the results of his telescopic observations. What he saw shook the world. The heavens above were no longer immutable and perfect, but had lumps and oddities all their own. In his g roundbreaking scientif ic text, "Siderius Nuncius," he described the three key observations that f inally overthrew the medieval thinking of his time: the mountains and valleys of the Moon, the "Medician" stars surrounding Jupiter and the phases of Venus. All three amazing discoveries served to help humanity understand a new and bigger universe than had been previously imagined. And this year we celebrate it. The IYA2009 was established by the International Astronomical Union and UNESCO to "help the citizens of the world rediscover their place in the universe through the day- and night-time sky, and thereby engage a personal sense of wonder and discovery." To this end, the IYA has established a series of cornerstone projects which astronomy professionals and amateurs can use to promote the wonders of the night sky. Of these 10 global initiatives, a few are truly appropriate for our club. The core effort is simply to have people look at the sky, possibly through a telescope. Every AAA member who has a telescope can do this by simply going to a street corner on a clear night and persuading passersby to take a look. You'll be surprised at the positive response. My paper at the AAS conference outlined my 100 Nights of Astronomy. Every Wednesday and Saturday night this year, I hope to get New Yorkers to look through my telescopes. I've already started in Inwood Hill Park. On January 21, I kicked off the effort in 20-degree weather. A small group stuck with me, and we were occasionally rewarded with breaking clouds. I got to talk with a good bunch and Howard Fink showed up with a scope and two pairs of binoculars to help out. As we now, our skies are getting brighter. The generation that just got its f irst vote last year is the f irst to never have seen the Milky Way. It's our job to help show people that light pollution not only takes away celestial wonders but also costs New York City millions of dollars in wasted electricity. In addition, lack of darkness has adverse health effects on nocturnal wildlife. Did you know that the vertical column of light above the Luxor Hotel in Las Vegas is so bright that birds fly into it, are frightened to leave the light so fly until they die from exhaustion? There are also preliminary indications that there are links between lack of melatonin in humanas and cancer. And glare bombs we all hate so much can be shown to make parks less safe from criminals. I attended a dark-skies workshop at the AAS meeting, and brought back resources for our organization. The 100 Hours of Astronomy effort is the largest and most important effort in which we as amateur astronomers can engage. On April 2-5 there is a global star party. I'm working to have at least one of those nights as a major public event in Inwood Hill Park. During these 100 hours, amateur and professional astronomers are urged to hold star parties, take a telescope to a mall, anything. The amazing eclipsing binary system Epsilon Aurigae has a 27-year cycle, and is poorly understood. The IYA hopes to enlist amateurs and professionals globally to watch the eclipse occur. The main star has a companion with a circumstellar disk that appears to be as large as Jupiter's orbit. I plan to be on the top of Inwood Hill with a large scope and 100 Hours continued on back page

Have You Renewed Your Membership?


W

HAT'S

UP

Comet Lulin moves swiftly into the evening sky this month.

By Tony Hoffman
The Sky for February 2009
A Lulu of a Comet. After 2007, a banner year for comets with the exceptional performances of comets McNaught and Holmes, 2008 was a letdown for comet observers. This year is getting off to a decent start with the arrival of Comet Lulin, which is expected to reach naked-eye visibility (at least from dark-sky sites) as it traverses the midnight sky in late February. Comet Lulin was discovered last July by Quanzhi Ye, a 19-year-old student at Sun Yat-Sen University in Guangzhou, China, on images taken by Chi-Sheng Lin of the Lulin Observatory Sky Survey. Although not off icially an amateur discovery, it's another triumph for a cadre of (mostly young) Chinese amateurs who avail themselves of a range of imaging techniques in astronomical research and discovery. Ye has also discovered comets in SOHO images and asteroids in Spacewatch images, as well as in photos from the Lulin survey, for which he is chief investigator. The survey uses a 16-inch telescope in Taiwan. Comet Lulin has been dubbed the "Comet of Cooperation" by the Chinese press due to its discovery through collaborative efforts of both Taiwanese and mainland astronomers. Comet Lulin lies outside of Earth's orbit, which will make it visible in a dark sky well away from the Sun. It passed perihelion on January 15, and will make its closest approach to Earth on February 24, when it will be 0.41 AU away. Lulin has an unusual orbit, nearly in the plane of the ecliptic but retrograde, moving around the Sun in the direction opposite that of the planets. This will seem to make it move very quickly. It starts the month in Libra in the morning sky, moves through Virgo, passing near Spica at midmonth (when it will rise before midnight), passing Saturn on February 23 and Regulus in Leo on the 27th. It will be opposite the Sun on the 26th, and visible most of the night. Saturn Unringed. Venus will continue to dazzle observers

in the early evening sky, blazing at magnitude -4.8 at midmonth, when it will show a fat crescent 36 arc-seconds across to observers. (I've had several non-astronomer friends ask me recently what that ultra-bright orb they've been seeing is.) Saturn rises as Venus is setting, and a telescope reveals an unusual sight: the rings are gone. They're invisible because they're nearly edge-on to us, though you may be able to see the shadow of the rings as a thin black line on the planet's disk. February 2 First-quarter Moon at 6:13 p.m. February 7 Moon at perigee. February 9 Full Moon at 9:49 a.m. February 11 Moon lies near Saturn. February 13 Mercury at greatest elongation in morning sky. February 15 Comet Lulin lies near Spica. February 16 Last-quarter Moon at 4:37 p.m. February 17 Mars lies 0.6 degrees from Jupiter in morning twilight; Moon lies near Antares. February 19 Venus at greatest brilliancy (magnitude -4.8). February 22 Moon lies near Mercury and Jupiter. February 23 Moon lies near Mars; Mercury passes 0.6 degrees from Jupiter; Comet Lulin lies near Saturn. February 24 New Moon at 8:35 p.m. February 25 Asteroid 1 Ceres at opposition.February 26 Comet Lulin at opposition. February 27 Moon lies near Venus; Comet Lulin lies near Regulus. g

Mercury Overtakes Jupiter in the Evening Sky
By Joseph A. Fedrick
Mercury emerged from the solar glare in the southwest to appear approximately 3 degrees below Jupiter on December 29. A thin crescent Moon with bright earthshine (old Moon in new Moon's arms) appeared within 5 degrees to the upper left (southeast) of Jupiter. Jupiter and Mercury easily f it into the same f ield of view in my 10x50 binoculars. The Moon and Jupiter also f it to the same f ield of view but all three objects did not quite f it in to the same f ield of view. Rather, they f it into overlapping f ields of view. By December 30, Mercury had closed to within 2 degrees to the lower right of Jupiter and then to within approximately 1 1/2 degrees of Jupiter by December 31. The crescent Moon and Venus then f it into the same f ield of view in the binoculars but were 30 degrees to the Southeast (upper left) of the JupiterMercury pair. By January 1, Mercury was already pulling away at approximately 2 degrees for Jupiter and higher up in the sky. By January 3, Mercury was approximately 5 degrees to the Mercury continued on page 10

2


A Message from AAA President Richard Rosenberg
Hello members: The new year got off with a bang on January 2 with a standing-room-only audience at our lecture. One of our most popular speakers, Robert Nemiroff of Michigan Technological University and Astronomy Picture of the Day showed off the best images of 2008 (see page 4). We saw pictures that solved problems, unearthed new questions or were simply beautiful. If you missed the talk, Dr. Nemiroff has allowed us to put his PowerPoint presentation on our website (www.aaa.org), which we shall do shortly. Our next lecture will take place February 20 (note the date) when Joseph Patterson of Columbia University will speak on "The Center for Backyard Astrophysics." On January 13, I spoke to another standing-room only audience (well, there were only about 30 seats) at the beautiful Charles A. Dana Center at the northern end of Central Park. Although clouds prevented the scheduled observing session from taking place, we showed off the winter sky using a planetarium program and had a far-ranging discussion on many areas of astronomy. These meetings illustrated an important point. There are a lot of people out there who really like astronomy but have little or no knowledge of the AAA or other organizations that can satisfy their interest. Let's be missionaries for astronomy. The comet is coming! In February, Comet Lulin should be visible with binoculars or telescope from the city (see page 2). It's predicted to peak at about magnitude 6 late in the month, when it will be visible at a reasonable hour. Look February 23 when Lulin will be near Saturn. Unless the comet goes the way of Kohoutek we'll have special observing sessions to view it. Check our website or give me a call. With help from John Swierzbin and Ken Levy, the telescope on the roof of the Solaria condominium in Riverdale is getting close to operational. We hope to have a public observing session there in March. I'll have more info next month. As you read this, we've just held our first event at our new headquarters. I hope you were there. The next meeting there, of our Observers' Group, will be from 7 to 9 p. m. February 24. If the sky is clear, we'll follow the meeting with observing, and we just might spot a comet. Thank you for your terrific response to our renewal request. Already more than two-thirds of our membership have renewed and we have a significant number of new members. If you haven't got around to it, dues are only $25. As a member you can receive a year's subscription to Sky & Telescope for only $32.95, or one- or two-year subscriptions to Astronomy magazine for $34 and $60, respectively. Send your check to the Amateur Astronomers Association, Box 383, Gracie Station, New York, NY 10028.

AAA Talk Feb. 20: Backyard Astrophysics Group
Joseph Patterson, professor of astronomy at Columbia University, will address the AAA on Friday, February 20 on "The Center for Backyard Astrophysics." The free public lecture is at 6:15 p. m. in the Kaufmann Theater of the American Museum of Natural History. "Astronomy, like the building of pyramids, has always relied on organizing the work of many people," Patterson notes. "In time and frequency, small telescopes scattered around the Earth can greatly outperform a single behemoth. In this age of computers and electronic mail, it's likely that these advantages will now cede leadership in the study of variable stars back to amateur astronomers. "The Center for Backyard Astrophysics is one such organization. It's a collaboration of amateur and professional astronomers to study light curves of cataclysmic variables. We now routinely obtain the best data in the world on this subject, and accidentally stumble on other gems as well, including the f irst-ever gravitational lens found in the Sun's vicinity." The website for the center, whuich was established in 1995, is http://cbastro.org. Discussing his career, Patterson says whimsically: "I AAA Talk continued on page 10

3


Top Astronomy Pictures of 2008 Dazzle the AAA
By Terrell Kent Holmes
Speaking with enthusiasm and a wry, self-effacing sense of humor, Dr. Robert J. Nemiroff, professor of physics at Michigan Technological University, delivered the January 2 AAA lecture on "The Best Astronomy Pictures of the Day, 2008". In 1995 Nemiroff co-founded the website Astronomy Picture of the Day (APOD), whose archive contains the largest collection of annotated astronomical images on the Internet. Nemiroff used a diverse selection of pictures as points of departure to discuss other pertinent issues in astronomy. Describing the process as "chaotic," Nemiroff explained how APOD chooses its photos. "We get sent lots of images, and unfortunately we reject [at a ratio] of about 10 to 1. My in box is usually f illed every day with really good images, and some not so good images. Also, we're on the press-release e-mail lists of the American Astronomical Society and many major observatories, so whenever they have something we get an e-mail. I also read some astronomy blogs to see if I missed something." The selection of photos from the past year covered an impressive range of issues and phenomena. The heavily pixeled photograph of Asteroid TU24, a near-Earth object, brought to mind Salvador DalЛ's similarly distorted painting of Abraham Lincoln. After showing photos taken in 2007 and 2008 to show the changes in Mars' angular diameter, Nemiroff explained that "Every year or so e-mails circulate [stating] that Mars is going to be as large as the Moon. And it never is and it never will be. We don't have the budget for it." He used a photograph of Makemake, a Kuiper Belt object designated as a dwarf planet, to discuss how the solar system has been expanded to include objects that were known about but unclassif ied, and to make a case for not only restoring Pluto's planetary status but actually making it a fully-grown planet. Nemiroff described the Sun as acting "a little bit strange" in that it had very few sunspots last year. "Even the biggest, brightest object in the sky is doing things that are [unpredictable]," Nemiroff said. "The activity of the Sun is actually important because it affects satellites that go around Earth. So if your cell phone is bouncing off a satellite it might be knocked out by a big solar event. And if we can predict when that happens we might be able to minimize the effect on the satellites." Planetary fly-bys were also touched on. Photos taken by the Mercury exploration probe, MESSENGER, led Nemiroff to describe Mercury's landscape of craters and long rays as looking something like a watermelon. MESSENGER will establish an orbit in 2012 to study the planet in greater detail. Everybody says there can't be anything new to learn about Mercury," Nemiroff said, "but it's not true." A Cassini fly-by of the Saturnian moon Enceladus also provided some compelling images. Nemiroff described it as "probably the most interesting object in the solar system [observed] in the past decade." Enceladus is a top candidate for harboring life, especially with the possibility of liquid water being concealed. One of NASA's long-term goals is to possibly land a space probe on Enceladus' surface. The problem may not be with funding the project but f inding a suitable place to land because the moon's surface may be problematic. Some of the most exciting photos taken in the past year were of planets circling other stars. One was of a planet larger than Jupiter orbiting Fomalhaut, a star 25 light-years away in Piscis Austrinis (the Southern Fish). Another photo showed three planets, all more massive than Jupiter, orbiting another star 100 light-years away. "It's interesting that we're actually able to see planets around other stars," Nemiroff said. "We always thought there were planetary systems like our solar system out there, but it's great to have actual conf irmation." A refreshing aspect of the lecture was its humanistic thread. For example, Nemiroff used photos of a total solar eclipse over China to illustrate how people have the same reactions to the same events in spite of cultural differences. In photos of the recent conjunction of Venus, Jupiter and the crescent Moon, the three objects formed a smiley face, with the crescent Moon as the mouth and the planets as the eyes. "We actually got a whole bunch of images, lots of smiley faces, [and] tried to exclude the frowns," Nemiroff said. Perhaps the most lasting image of the presentation, though, was of the International Space Station transiting the Sun, a hopeful speck against the great face of our nearest star. It was a perfect metaphor for our true place in the universe, and our timeless, unending quest to solve its mysteries. To view the Astronomy Photo of the Day and visit the archives, log on to apod.nasa.gov. g

4


Palomar: The 60-Year-Old Gift that Keeps On Giving
By Edward J. Fox
"The Palomar Telescope is very dear to my heart." So stated Dr. Ben R. Oppenheimer, assistant curator of the Division of Physical Sciences of the American Museum of Natural History, introductory to a special program January 15 at the Hayden Planetarium in celebration of the United Nations' International Year of Astronomy. He continued, "I spent more than 150 nights working there as a student and I continue to work there on a new instrument we have installed to study exoplanets." He added, "The real star of the evening is the 1-million pound-Palomar 200-inch Hale Telescope." Oppenheimer introduced documentary f ilmmakers Robin and Todd Mason, to present their recently broadcast Public Broadcasting System program "The Journey to Palomar." The Masons spent years researching and producing their f ilm, which documents the efforts of George Ellery Hale to develop a progression of ever-more-powerful telescopes, which led to the Palomar Hale Telescope opening in 1948. According to Todd Mason, "Hale was a hugely important person in science and astronomy. He wanted science in America to be the best in the world." The film begins with the description of a young Hale in the milieu of the turn-of-the-last-century, fast-paced world of a rapidly growing Chicago. It was in this "anything-is-possible" atmosphere that Hale's father became wealthy in the elevator business. That wealth provided Hale with a private observatory and allowed him to start pursuing his avid interest in astronomy. He became aware over time that he could only further his interest in learning about the universe with ever-more-powerful telescopes. They had to be able to gather more light to explore the vastness of space. When they reached the limit in size for a refractive lens, they had to be larger reflecting scopes. When they reached the limits of the tried and true glass technologies of the day, new directions had to be explored. Lacking governmental support, Hale had to convince very wealthy men to f inance his "eye in the sky" interests. This was a time when his efforts were frowned on by other astronomers. Simon Newcomb, a renowned astronomer, said, "We are probably nearing the limit of all we can know about astronomy." After initial funding by a couple of Chicago-area millionaires, the progression of size and higher costs led Hale f irst to Andrew Carnegie and ultimately to John D. Rockefeller Jr. The movie describes the tribulations of every progressive project, such as the diff iculties of dealing with larger glass lenses and reflective mirrors. Testing the evolving limits of the glass industry are detailed. On the f irst large reflector telescope, an observation platform collapsed under its own weight, fortunately before the telescope was in operation. There were the excruciating waits of about a year at a time to slowly cool the glass in the annealing processes. There were years of polishing the lenses and mirrors. Hale died in 1938, 10 years before the Palomar scope saw f irst light in 1948, having been delayed by World War II. The instrument was named in his honor. A Wilson realize opened major benef it of Hale's 100-inch telescope at Mount is that it provided Edwin Hubble with the platform to that there are galaxies outside of the Milky Way. It the universe!

Oppenheimer was extravagant in praising the design of the Palomar facility. He believes the design is so good it's conducive to good science, since problems due design flaws don't manifest themselves and therefore don't hinder the scientists. The facility has been fully booked for the past 60 years. Due to improvements in the technologies, he estimates the facility is 100 times as powerful as it was when into service in 1948. The advent of digital-photography technologies and adaptive optics-including laser-generated guidance--have contributed to the improvements. In response to a question about just looking through an eyepiece of the telescope to view the heavens, Oppenheimer said that for years this was possible only on Christmas, when the telescope wasn't booked. The workers could look through an eyepiece inserted into a certain place. Now, not even that is possible since that's now the pathway for laser technologies. Oppenheimer believes the Hale Telescope has a productive life of about 10 more years. Even then, he envisions it will be useful in the production of repetitive images, where the science is to be found in identifying differences in the images. For further information: www.astro.caltech.edu/palomar/ or www.pbs.org/thejourneytopalomar/. g

How to Contact the AAA
If you want to join, volunteer your time, participate in events, have a question or need to change your address, email secretary@aaa.org, or leave a message at AAA hq: (212) 535-2922. Also, visit us on the web at www.aaa.org. If you're interested in writing an article for Eyepiece, contact editor Dan Harrison at editor@aaa.org.

5


Review: Spectacular Book on the Hubble
By Dan Harrison
If you like looking at spectacular pictures taken by the Hubble Space Telescope--and who doesn't?--"Hubble: Imaging Space and Time" is a book you'll enjoy over and over again. But the book (National Geographic, $50), by David Devorkin and Robert W. Smith, is far more than a cornucopia of some 150 pages of one great picture after another. Interleaved among the images is a well-written history of the instrument that has revolutionized modern astronomy. The book begins with two forewords, one by Hayden Planetarium director Neil deGrasse Tyson. He notes that "Hubble is the f irst and only space telescope to image the universe in visible light, becoming for us a supreme version of our eyes in space." Hubble's appeal, Tyson observes, came during "an exponential growth of the public's access to the Internet." And most space telescopes have limited life expectancy, whereas Hubble was "designed, built and launched to be serviced...And Hubble's talents were not simply sustained...mission by mission, they were vastly improved." Both Tyson and the excellent history of the Hubble that weaves its way through the pictures note that when NASA announced in 2004 that Hubble wouldn't receive its f ifth servicing mission, there was an outcry--with the loudest voices not scientists, but the general public. "The public took ownership of the Hubble," Tyson notes. "I know of no time in...history...when the masses banded together to save a scientif ic instrument." Or as the book puts it, "In the opinion of many, the Hubble was the most productive scientif ic instrument ever, one with which they felt a very personal involvement. Furthermore, an upgraded Hubble would produce still more exciting science...." While the book is a paean to the Hubble, it hardly pulls its punches on negative events in the telescope's history. One of these was the infamous spherical aberration which was detected less than a month after the April 1990 launch. "...if there had been cross-checks in the program to catch such a mistake, it might have been corrected. There were not. With a strained budget and no additional money for extra tests, the small number of people who knew that there might be a problem had rung no alarm bells. The result was a misshapen primary mirror." Later on, the authors note that after this and other f ixes, "No longer was the Hubble synonymous with trouble. Another key stem in [its] public rehabilitation...came in 1994" when it was used to observe the Shoemaker-Levy comet's smashing into Jupiter. "...the HST's extremely public role in observing [the collisions] underlined its capabilities." By March 2002, the authors state, the HST "was in many ways a very different observatory from the one f irst launched in 1990. All of the original scientif ic instruments had been replaced by more powerful ones...In the end, the Hubble's scientif ic performance had even exceeded the hopes that had sustained its advocates over so many years. By early in the 21st century...it had come to be widely regarded as the most productive observatory ever built." The book is also interesting when it discusses the nethodology of the Hubble, as illustrated by the following excerpts: "The key in getting Hubble observing time is persuading the granters that the goals of the proposal are worth the sacrif ice of other potential goals. For every individual or team that succeeds in getting a run, many others are left without the use of Hubble's eyes." "One factor aiding the decision over who gets an observing run is the general value of the data, beyond the specif ic uses the proposers may have. Ultimately, from this observing run, a contribution will be made to the Hubble Data Archive, which serves as the repository for collected data. In this manner, the data gathered will be of use to astronomy long after [analysis]." "An observing run on the HST is usually a fully automatic programmed process. For this reason, once the observing schedule is established, almost endless little details have to be thrashed out ahead of embarking on the actual observations." "There are two major steps in bringing the data to the end user: downloading it...and calibrating and correcting it for both systematic errors due to the instrument and random errors due to momentary peculiarities of the space environment." You may not have known--I didn't--that full-color images associated with the Hubble are actually composites of three different images of the same object taken through Review continued on back page

6


Highlights of January AAS Meeting in California
Scientists have revised the mass of the Milky Way, saying it's half again as heavy as thought, on par with the Andromeda Galaxy. The Milky Way also spins much faster than thought. Astronomers measured distances and motions of different areas of the Milky Way. The galaxy's speed at the position of our solar system, 28,000 light-years from the galactic center, is up to 600,000 mph faster than thought. The new mass is 3 trillion solar masses, so the Milky Way exerts a greater gravitational pull that increases the likelihood of collisions with Andromeda or smaller nearby galaxies. Regions of prolif ic star formation were observed across the Milky Way. Observations also shed light on the galaxy's spiral structure. Most star-forming regions don't follow a circular path as they orbit the galaxy. Instead, they move slower than other regions on elliptical orbits. These are the result of spiral density wave shocks, which can take gas in a circular orbit, compress it to form stars and cause it to go into a new, elliptical orbit. Measurements indicate our galaxy probably has four, not two, spiral arms of gas and dust that form stars. Recent Spitzer surveys suggest older stars are found mostly in two spiral arms. Two embryonic stars discovered a few light-years from the Milky Way's center show stars can form in the potentially destructive reach of the black hole at our galaxy's center. The stars were caught in the act of forming. Because gas and dust between Earth and the galactic center blocks visible light from getting out, astronomers used infrared and radio wavelengths to see the region. They found the protostars at 7 and 10 light-years from the galactic center. The f inding suggests molecular gas at the Milky Way's center from which stars form is denser than thought. The gas makes it easier for the self-gravity of the condensing cloud to overcome the strong pull of the black hole and collapse to form new stars. Fourteen young stars racing through clouds of gas, creating brilliant arrowhead structures and tails of glowing gas, have been revealed by Hubble. They represent a new type of runaway bright, high-velocity stellar interloper. Strong stellar winds suggest they're just a few million years old. They appear to be medium-sized, up to eight times more massive than the Sun. The stars' youth is also shown because shapes of nebulas around dying stars are very different from what's seen around these stars, and old stars are almost never found near dense interstellar clouds, as these are. Bow shocks the stars created could be 100 billion-1 trillion miles wide. These bow shocks indicate the stars are traveling more than 112,000 mph, f ive times faster than typical young stars. Astronomers think the young stars are runaways that were jettisoned from clusters they were born in. New observations of chewed-up asteroids around white dwarfs bolster the idea that the Earth and other rocky planets in our solar system are far from alone in the universe. Astronomers used Spitzer to see six white dwarfs and found the signature of asteroid debris circling them. Analysis of light from the systems shows the rings are made of some of the same materials as rocky bodies in our solar system. Spitzer had previously observed shredded asteroid pieces around two white dwarfs. New observations bring the count of white dwarfs with asteroid debris to eight. About 1% of white dwarfs are estimated to have these signatures. All eight white-dwarf systems show signatures of a glassy silicate mineral similar to olivine, which is common on Earth. Spectra of asteroid debris also showed no carbon signature, another similarity to asteroids and rocky planets in our solar system. One asteroid is thought to have broken apart within the last million years or so in each white-dwarf system. A team of astronomers has found a strange noise from the distant cosmos that booms six times louder than expected. Analysis ruled out primordial stars or known radio sources, including gas in the oute