Astronomy Magazine News Article – Released:1/11/2012
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Rare ultra-blue stars found in neighboring galaxy’s hub
Clusters of Stars Crackle and Pop to Tell the Story of Star Formation
This enormous section of the Milky Way galaxy is a mosaic of images from NASA's Wide-field Infrared Survey Explorer, or WISE. The constellations Cassiopeia and Cepheus are featured in this 1,000-square degree expanse. Image credit: NASA/JPL-Caltech/UCLA
Astronomers trying to understand the formation of massive clusters of stars are getting a better idea of how the process works from the latest images and data from the WISE spacecraft. NASA’s Wide-Field Infrared Survey Explorer has captured a vast stretch of nearly a dozen nebulae popping with new star birth, which is helping to narrow the field of possible star-forming scenarios.
“We are trying to understand how huge clusters of stars form at the same time from a large cloud of gas,” said Xavier Koenig from Goddard Space Flight Center, speaking at a press briefing from the American Astronomical Society meeting this week. “We have two possible pictures of how this process works and WISE is helping us piece together the chain of events.”
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Astronomers discover two planets that survived their star’s expansion
Astronomy Magazine News Article – Released:12/22/2011
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A galaxy blooming with new stars
Astronomy Magazine News Article – Released:12/16/2011
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Massive stars are born as giants
Astronomy Magazine News Article – Released:12/8/2011
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In a star’s final days, astronomers hunt “signal of impending doom”
Astronomy Magazine News Article – Released:12/1/2011
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Magnetic fields set the stage for the birth of new stars
Astronomy Magazine News Article – Released:11/16/2011
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Antique Stars Could Help Solve Mysteries Of Early Milky Way
The Milky Way is like NGC 4594 (pictured), a disc shaped spiral galaxy with around 200 billion stars. Above and below the galactic plane there is a halo, which includes older stars dating back to the galaxy’s childhood billions of years ago. In principle they should all be primitive and poor in heavy elements like gold, platinum and uranium. New research shows that the explanation lies in violent jets from exploding giant stars. Credit: ESO
Utilizing ESO’s giant telescopes located in Chile, researchers at the Niels Bohr Institute have been examining “antique” stars. Located at the outer reaches of the Milky Way, these superannuated stellar specimens are unusual in the fact that they contain an over-abundance of gold, platinum and uranium. How they became heavy metal stars has always been a puzzle, but now astronomers are tracing their origins back to our galaxy’s beginning. (…)
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Different Supernovae; Different Neutron Stars
Artist concept of a neutron star. Credit: NASA
Astronomers have recognized various ways that stars can collapse to undergo a supernova. In one situation, an iron core collapses. The second involves a lower mass star with oxygen, neon, and magnesium in the core which suddenly captures electrons when the conditions are just right, removing them as a support mechanism and causing the star to collapse. While these two mechanisms make good physical sense, there has never been any observational support showing that both types occur. Until now that is. Astronomers led yb Christian Knigge and Malcolm Coe at the University of Southampton in the UK announced that they have detected two distinct sub populations in the neutron stars that result from these supernova.
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Study shows first stars were not monstrous
Astronomy Magazine News Article – Released:11/11/2011
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Spiral arms point to possible planets in a star’s dusty disk
Astronomy Magazine News Article – Released:10/24/2011
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Water vapor reveals how stars form around a black hole in the early universe
Astronomy Magazine News Article – Released:10/24/2011
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Blue stragglers: Astronomers discover how mysterious stars stay so young
Astronomy Magazine News Article – Released:10/19/2011
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“Failed stars” galore with one youngster only six times heftier than Jupiter
Astronomy Magazine News Article – Released:10/12/2011
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How single stars lost their companions
Astronomy Magazine News Article – Released:9/16/2011
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Hubble movies provide unprecedented view of supersonic jets from young stars
Astronomy Magazine News Article – Released:8/31/2011
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Comet Garradd Passes Ten Thousand Stars
Comet Garradd continues to brighten as it drifts across the northern sky.
Falling stars: All about shatter cones
When sleuthing a potential or known meteorite impact crater, scientists look for clues. One of these clues is a geological feature known as a “shatter cone.” These objects — also called shocked rocks — bear the patterns of high-energy impacts. They are found only in the bedrock under meteorite impact craters or near underground nuclear explosions. This gives us some idea of the power of a meteorite impact.
This shatter cone comes from the Sierra Madera crater located in southwestern Pecos County, Texas. The crater is 8 miles (13 kilometers) in diameter. Estimates place its age at less than 100 million years. // All photos by Mike ReynoldsShatter cones show that the rocks near the impact site have been subjected to a significant shock. The pressures associated with such impacts lie between 29,000 pounds per square inch to more than 4 million psi. Atmospheric pressure at sea level measures 14.7 psi, so such impactors create pressures some 270,000 times greater than our bodies normally experience.
Shatter cones are one type of impact evidence beyond the bowl-shaped crater. But the crater might have been erased from sight due to erosion, or it may be covered by growth. Impact “glasses,” breccias, and related material also demonstrate the extremes of an impact. Perhaps one of the most famous sites is the Sudbury Crater in Ontario, Canada, where explorers have found a rich array of impact materials — and, in some cases, are mining them.
If you examine a shatter cone, one of the first things you’ll note is the thin grooves in the rock. These grooves — call striae — form a unique branching, fractured pattern that look like a horse’s tail. Many shatter cones have a characteristic conical shape, with repeating conical patterns in the shatter cone.
The type of shatter cone formed and its specific characteristics depends on the type of rock the meteorite struck. The striae are easier to recognize in fine-grained material, such as limestone, and harder to see in coarse-grained material.
A massive impact 1.85 billion years ago created the Sudbury crater in Ontario, Canada. The blast formed the second-largest impact crater on Earth. Some of the energy from the explosion transferred to the rocks below the crater, forming shatter cones like this one.Shatter cones can and will be altered over time by Earth’s natural processes. So it is possible a geologist might not easily identify an impact site as such due to erosion or other natural geologic processes.
Shatter cone sizes can vary from microscopic to some 33 feet (10 meters) in length. The largest shatter cone found was at the Slate Islands in Terrace Bay, Ontario.
Meteoriticists are still theorizing how shatter cones form. Theories include the idea that the impact wave compresses the rock. Or perhaps a rebound effect creates tension after the impact pressure subsides in the rock. Shatter cones were first described by Branco and Fraas in 1905 in the Steinheim impact structure in Germany. They initially attributed them to a volcanic eruption.
In my meteorite and crater research arsenal is a selection of shatter cones from various impact sites around the world. The variations, much like meteorites, are indicative of the areas impacted. Sometimes shatter cones are the only evidence that remains from impacts that occurred millennia ago. One does not see as many shatter cones on the market as meteorites and tektites. I try to obtain shatter cone samples — either in person at a site I am researching or in a trade — to give me a better picture of impacts. Plus, shatter cones represent the immense power of such an event, and they are something I can hold in my own two hands.
NASA’s WISE mission discovers coolest class of stars
Astronomy Magazine News Article – Released:8/24/2011
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White Dwarf Stars Consume Rocky Bodies
This artist's concept shows a star encircled by a disk of gas and dust, the raw materials from which rocky planets such as Earth are thought to form. Image credit: NASA/JPL-Caltech
“I love rocky road… So won’t you buy another gallon, baby…” Yeah. We all love rocky road ice cream, but what do stars like to snack on? In the case of the white dwarf star it would appear that a rocky body – similar to Earth – could be a preferred blend. At one time astronomers thought the dense, elderly stars were just gathering dust… but apparently it’s the “bones” left-over from a planetary knosh. (…)
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Neighbor galaxy caught stealing stars
Astronomy Magazine News Article – Released:7/19/2011
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Evolved stars locked in fatalistic dance
Astronomy Magazine News Article – Released:7/13/2011
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“Zombie” stars key to measuring dark energy
Astronomy Magazine News Article – Released:7/5/2011
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Slowing Down Stars
Forming Star's Magnetic Field Interacting With Disc Credit: NASA/JPL-Caltech/R. Hurt (SSC).
One of the long standing challenges in stellar astronomy, is explaining why stars rotate so slowly. Given their large masses, as they collapsed to form, they should spin up to the point of flying apart, preventing them from ever reaching the point that they could ignite fusion. To explain this rotational braking, astronomers have invoked an interaction between the forming star’s magnetic field, and forming accretion disc. This interaction would slow the star allowing for further collapse to take place. This explanation is now over 40 years old, but how has it held up as it has aged?
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How to learn a star’s true age
Astronomy Magazine News Article – Released:5/23/2011
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Hubble Space Telescope finds rare “blue straggler” stars in the Milky Way’s hub
Astronomy Magazine News Article – Released:5/26/2011
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Hubble Finds “Oddball” Stars in Milky Way Hub

Astronomers using the Hubble Space Telescope to peer deep into the central bulge of our galaxy have found a population of rare and unusual stars. Dubbed “blue stragglers”, these stars seem to defy the aging process, appearing to be much younger than they should be considering where they are located. Previously known to exist within ancient globular clusters, blue stragglers have never been seen inside our galaxy’s core – until now.
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Free-floating planets may be more common than stars
Astronomy Magazine News Article – Released:5/18/2011
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Falling Stars: Harvey Harlow Nininger
Perhaps the most-famous meteoriticist of all time is Dr. Harvey Harlow Nininger (1887–1986). His fascination with meteorites started when he witnessed a fireball in 1923. Nininger, a biologist, yearned for the opportunity to collect and research meteorites as a full-time endeavor in lieu of his college professorship. He spent most of his career at McPherson College in Kansas. Unfortunately, he lived in an era when most scientists ridiculed those who recovered, studied, and researched meteorites for delving into an area then considered of little or no scientific use.
Harvey Harlow Nininger was the father of the science of meteoritics. He amassed a vast collection of meteorites by spreading the word to common folk that he would pay cash for “strange and unusual” rocks. // Photo courtesy Aerolite MeteoritesRegarding space rocks, Nininger was self-taught. Throughout his illustrious career, he assembled the world’s largest personal collection of meteorites. His recovery work and research led to the revival of the science of these objects. He loved to talk meteorites, anywhere and anytime, to anybody who would listen. Nininger himself noted that he had given hundreds of lectures through the years: in colleges, elementary and high schools, and even at Carnegie Hall. I don’t know many people in astronomy (and especially meteorite research) who have pulled that off.
Nininger also visited farmers and ranchers, inquiring about unusual rocks they might have found. He later revisited the individuals, often being rewarded with a new find. He adopted a successful method, offering to purchase meteorites others had found. Most farmers and ranchers cleared their fields of rocks anyway. But to perhaps make some extra cash, they would go back to those rock piles and look for unusual specimens like those Nininger had described and showed to them.
Initially, Nininger found no financial support for recovering meteorites, so he financed his own endeavors and became a full-time meteoriticist in 1930. His recoveries, part of which he sold to earn an income, became the cornerstone of his collection.
In his autobiography, Find a Falling Star, he wrote, “The Paragould meteorite had profound effects on our lives. I have never ceased to regret parting with it, but I had paid a price too high, and was forced to give up either the specimen or my dream of making meteorites a new vocation. And Paragould, with the $ 2,000 profit it brought, was the way to my dream.”
In 1946, Nininger and his wife, Addie, founded the American Meteorite Museum, initially near Barringer Meteor Crater in Arizona. In 1953, they relocated the museum to Sedona, Arizona, where it remained until 1960. At that time, Arizona State University purchased roughly half of the Nininger collection. Visitors to that campus can still see a selection of his meteorites on display.
In 1933, the Field Museum of Natural History in Chicago, Illinois, founded the Society for Research on Meteorites. Nininger was the first secretary-treasurer of the group, which included 57 charter members. This organization eventually became the Meteoritical Society, which now boasts 950 scientists and amateur meteoriticists from more than 33 countries.
"A Comet Strikes the Earth" by H. H. Nininger was first published in 1942. Later editions included an oxidized meteorite fragment from the Canyon Diablo (Barringer Meteor Crater) site in northern Arizona. // Michael E. Bakich libraryDuring his illustrious career, Nininger wrote 162 papers and several books. His most-famous books include Our Stone-Pelted Planet (1933), A Comet Strikes the Earth (1942), Arizona’s Meteorite Crater (1956), Ask a Question About Meteorites (1961), and Find a Falling Star (1972).
Collectors consider all of Nininger’s books collector’s items, and some can be difficult to find. My favorite is his autobiography, Find a Falling Star. In the book, Nininger details many of his adventures in meteorite recovery and research. If you can locate — and afford, if you must have a first edition — a copy of Find a Falling Star, buy it. This book will inspire you, as it has done many others (including me).
Harvey H. Nininger was the pioneer of modern meteorite research, and many consider him the father of contemporary meteoritics. He led the way when others thought the science was frivolous. His collecting methods, cataloging, and displaying of meteorites are in many ways still the standard. Nininger truly was a star.
Ultraviolet spotlight on plump stars in tiny galaxies
Astronomy Magazine News Article – Released:4/25/2011
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STEREO turns its steady gaze on variable stars
Astronomy Magazine News Article – Released:4/19/2011
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Newly merged black hole eagerly shreds stars
Astronomy Magazine News Article – Released:4/11/2011
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Kepler helps astronomers update census of Sun-like stars
Astronomy Magazine News Article – Released:4/7/2011
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Kepler mission helps reveal the inner secrets of giant stars for the first time
Astronomy Magazine News Article – Released:4/4/2011
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Exploding stars and stripes in Tycho’s supernova remnant
Astronomy Magazine News Article – Released:3/25/2011
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Companion Stars Could Cause Unexpected X-Rays

Many types of main sequence stars emit in the X-ray portion of the spectra. In massive stars, strong stellar winds ripping through the extended atmosphere of the star create X-ray photons. On lower mass stars, magnetic fields twisting through the photosphere heat it sufficiently to produce X-rays. But between these two mechanisms, in the late B to mid A classes of stars, neither of these mechanisms should be sufficient to produce X-rays. Yet when X-ray telescopes examined these stars, many were found to produce X-rays just the same.
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Stars gather in “downtown” Milky Way
Astronomy Magazine News Article – Released:3/22/2011
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Superfluid and superconductor discovered in star’s core
Astronomy Magazine News Article – Released:2/24/2011
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Hubble Zeroes in on Hot, Young Stars
Flocculent Spiral NGC 2841, in the constellation Ursa Major. Credit: NASA, ESA and Hubble
The Flocculent Spiral NGC 2841, shown above, is known for its profusion of young, blue stars. And yet, until recently, astronomers haven’t been able to use those stars as windows into the still-mysterious phenomenon of star formation.
Hubble’s most recent wide-field camera upgrade is changing that.
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NGC 2174: Stars Versus Mountains
It’s stars versus gas mountains in NGC 2174 and the stars are winning.
First stars in the universe weren’t lonely
Astronomy Magazine News Article – Released:2/4/2011
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Hubble finds that puny stars pack a big punch
Astronomy Magazine News Article – Released:1/11/2011
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Andromeda’s once and future stars
Astronomy Magazine News Article – Released:1/6/2011
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Magnetic Fields on O-Class Stars
Star classifications. Image credit: Kieff
The primary method by which astronomers can measure magnetic field strength on stars is the Zeeman effect. This effect is the splitting of spectral lines into two due to the magnetic field’s effect on the quantum structure of the orbitals. For massive O-class stars, their spectra are largely featureless in the visual portion of the spectra due to an insufficient number of atoms with electrons in the necessary orbitals to undergo transitions which can produce visual spectral lines. Thus, determining whether or not these stars have magnetic fields has been a unique challenge. A new paper from researchers at the University of Amsterdam, led by Roald Schnerr, looks for evidence of these fields in the form of synchrotron radiation.
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Herschel looks back in time to see today’s stars bursting into life
Astronomy Magazine News Article – Released:12/17/2010
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A swarm of ancient stars
Astronomy Magazine News Article – Released:12/9/2010
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Discovery triples the number of stars in the universe
Astronomy Magazine News Article – Released:12/2/2010
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Astronomers find Rosetta stone for T-dwarf stars
Astronomy Magazine News Article – Released:11/23/2010
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Kepler spacecraft takes pulse of distant stars
Astronomy Magazine News Article – Released:10/27/2010
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Neutron stars may be too weak to power some gamma-ray bursts
Astronomy Magazine News Article – Released:11/3/2010
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Cosmic dust clouds sprawl across a rich field of stars in
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Dust clouds and embedded newborn stars glow
The universe is filled
The Once and Future Stars of Andromeda