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  1. One of the trademarks of the Star Wars film episodes is the dreaded Death Star battle station that fires a beam of directed energy powerful enough to blow up planets. The real universe has such fireworks, and they are vastly more powerful than the Star Wars creation. These extragalactic jets are tearing across hundreds of light-years of space at 98 percent the speed of light. Instead of a battle station, the source of the killer beam is a supermassive black hole weighing many million or even a billion times the mass of our sun. Energy from the spinning black hole, and its titanic magnetic fields, shape a narrow jet of gas blasting out a galaxy's center. Hubble has been used over the past 25 years to photograph and rephotograph a jet blasting out the heart of the elliptical galaxy 3C 264 (also known as NGC 3862). Hubble's sharp vision reveals that the jet has a string-of-pearls structure of glowing knots of material. When these images were assembled into a time-lapse movie, they reveal – to the surprise of astronomers – a faster-moving bright knot rear-ending the bright knot in front of it. The resulting shock collision further accelerates particles that produce a focused beam of deadly radiation. The jet is moving so fast toward us it gives the illusion that it is traveling faster than the speed of light. But not to worry, the host galaxy is 260 million light-years away. We are seeing the jet as it looked before the dinosaurs appeared on Earth, and our planet was suffering a global mass extinction. View the full article
  2. Astronomers have spent decades trying to determine the oddball behavior of an aging star nicknamed "Nasty 1" residing in our Milky Way galaxy. Nasty 1 was identified as a Wolf-Rayet star, a rapidly evolving star that is much more massive than our sun. The star loses its hydrogen-filled outer layers quickly, exposing its super-hot and extremely bright helium-burning core. But Nasty 1 doesn't look like a typical Wolf-Rayet star. Astronomers using NASA's Hubble Space Telescope had expected to see a bipolar outflow of twin lobes of gas from the star, perhaps similar to those emanating from the massive star Eta Carinae. The astronomers were surprised, however, to find a pancake-shaped disk of gas encircling the star. The vast disk is nearly 1,000 times the diameter of our solar system. It may have formed from the interaction between Nasty 1 and an unseen companion star. The star may represent a brief transitory stage in the evolution of extremely massive stars. Nasty 1's nickname was derived from its catalog name of NaSt1. View the full article
  3. Globular star clusters are isolated star cities, home to hundreds of thousands of stars. And like the fast pace of cities, there's plenty of action in these stellar metropolises. The stars are in constant motion, orbiting around the cluster's center. Past observations have shown that the heavyweight stars live in the crowded downtown, or core, and lightweight stars reside in the less populated suburbs. But as heavyweight stars age, they rapidly lose mass, cool down, and shut off their nuclear furnaces. After the purge, only the stars' bright, super-hot cores remain, and they are called white dwarfs. This weight-loss program causes the now lighter-weight white dwarfs to be nudged out of the downtown through gravitational interactions with the heftier stars. At each encounter, the white dwarfs' orbits begin to expand outward from the cluster's packed center. Until these Hubble observations, astronomers had never seen the dynamical conveyor belt in action. The new Hubble results reveal young white dwarfs on their slow-paced 40-million-year exodus from the bustling center of the globular cluster 47 Tucanae in our Milky Way galaxy. View the full article
  4. The Andromeda galaxy is our Milky Way's nearest neighbor in space. The majestic spiral of over 100 billion stars is comparable in size to our home galaxy. At a distance of 2.5 million light-years, it is so close to us the galaxy can be seen as a cigar-shaped smudge of light high in the autumn sky. But if you could see the huge bubble of hot, diffuse plasma surrounding it, it would appear 100 times the angular diameter of the full Moon! The gargantuan halo is estimated to contain half the mass of the stars in the Andromeda galaxy itself. It can be thought of as the "atmosphere" of a galaxy. Astronomers using Hubble identified the gas in Andromeda's halo by measuring how it filtered the light of distant bright background objects called quasars. It is akin to seeing the glow of a flashlight shining through a fog. This finding promises to tell astronomers more about the evolution and structure of one of the most common types of galaxies in the universe. View the full article
  5. The universe is incredibly big. But how do astronomers know that? Billion-mile-long tape measures can't be found at the hardware store. Instead, astronomers use the expansion of the universe itself to establish milepost markers. The light from remote objects is attenuated and weakened as space stretches like a rubber band. The consequences are that starlight will look redder relative to a nearby star of the same temperature. When starlight is spread into its component color via spectroscopy, features in the light will be shifted to the red end of the spectrum. This "redshift" can be used to reliably calibrate distances. The challenge is the farthest objects in the universe are typically too faint for spectroscopy to work. So instead, astronomers deduce a galaxy's distance by precisely measuring its colors in visible and infrared light. This technique has found candidates for the farthest object in the universe. Now, in a synergy between the Hubble and Spitzer space telescopes, and the giant W. M. Keck Observatory, astronomers have set a new distance record to the farthest redshift-confirmed galaxy. It is so far away the light we receive left the galaxy over 13 billion years ago, and it is just arriving now. Hubble found the galaxy in deep-sky surveys, and Keck's 10-meter-diameter segmented mirror is powerful enough to collect a spectrum from the unusually bright galaxy. The new observations underline the very exciting discoveries that NASA's James Webb Space Telescope will enable when it is launched in 2018. View the full article
  6. NASA and ESA are celebrating the Hubble Space Telescope's silver anniversary of 25 years in space by unveiling some of nature's own fireworks – a giant cluster of about 3,000 stars called Westerlund 2. The cluster resides inside a vibrant stellar breeding ground known as Gum 29, located 20,000 light-years away in the constellation Carina. The comparatively young, 2-million-year-old star cluster contains some of our galaxy's hottest, brightest, and most massive stars. The largest stars are unleashing a torrent of ultraviolet light and hurricane-force winds that etch away the enveloping hydrogen gas cloud. This creates a fantasy celestial landscape of pillars, ridges, and valleys. View the full article
  7. Our Sun missed the stellar "baby boom" that erupted in our young Milky Way galaxy 10 billion years ago. During that time the Milky Way was churning out stars 30 times faster than it does today. Our galaxy was ablaze with a firestorm of star birth as its rich reservoir of hydrogen gas compressed under gravity, creating myriad stars. But our Sun was not one of them. It was a late "boomer," arising 5 billion years later, when star birth had plunged to a trickle. Astronomers compiled this story of our Milky Way's growth from studying galaxies similar in mass to our galaxy, found in deep surveys of the universe. Stretching back in time more than 10 billion years, the census contains nearly 2,000 snapshots of Milky Way-like galaxies. The analysis comprises the most comprehensive multi-observatory galaxy survey yet, and includes data from the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS), taken with NASA's Hubble Space Telescope. View the full article
  8. NASA and the Space Telescope Science Institute (STScI) have announced the selection of 17 new Hubble Fellows. STScI in Baltimore, Maryland, administers the Hubble Fellowship Program for NASA. The Hubble Fellowship Program includes all research relevant to present and future missions relating to NASA's Cosmic Origins Program. These missions currently include the Herschel Space Observatory, the Hubble Space Telescope (HST), the James Webb Space Telescope, the Stratospheric Observatory for Infrared Astronomy (SOFIA), and the Spitzer Space Telescope. The new Hubble Fellows will begin their programs in the fall of 2015. View the full article
  9. In 2007, Dutch schoolteacher Hanny van Arkel discovered a never-before-seen ghostly structure near a galaxy, while she was participating in an online amateur scientist project called Galaxy Zoo. The galaxy hosts a bright quasar that may have illuminated the apparition by hitting it with a beam of light from hot gas around a central black hole. Astronomers eagerly used the Hubble Space Telescope to do follow-up observations, which revealed knots of dust and gas in the "greenish blob." Assuming that this feature could offer insights into the puzzling behavior of active galaxies, Bill Keel of the University of Alabama, Tuscaloosa, initiated a search for other similar phenomenon. After all, where there's one strange blob there could be more. Keel had 200 volunteers look at archival data of 15,000 galaxies hosting quasars. In the end, he found eight other galaxies with bright active nuclei that have illuminated material far outside the radius of the galaxy. The eerie structures have looping, spiral, and braided shapes. Hubble's images show that they are like the remnants of galaxy collisions. View the full article
  10. In particle physics labs, like the Large Hadron Collider in Geneva, Switzerland, scientists smash atoms together to study the underpinnings of matter and energy. On the scale of the macrocosm, nature provides a similar experiment by crashing clusters of galaxies together. Besides galaxies and gas, the galaxy clusters contain huge amounts of dark matter. Dark matter is a transparent form of matter that makes up most of the mass in the universe. During collisions, the clouds of gas enveloping the galaxies crash into each other and slow down or stop. Astronomers found that the dark matter continued straight through the violent collisions, without slowing down relative to the galaxies. Their best explanation is that the dark matter did not interact with visible particles, and it also interacted less frequently with other dark matter than previously thought. Astronomers used the Hubble Space Telescope and Chandra X-ray Observatory to study 72 large galaxy cluster collisions. Chandra traced the hot gas, and Hubble saw how the invisible dark matter warps space and distorts the images of background stars. This allowed for the distribution of dark matter in the collision to be mapped. The finding narrows down the options for what this dark matter might be. View the full article
  11. Astronomers at the Space Telescope Science Institute and the Johns Hopkins University, both in Baltimore, Maryland, have created a new master catalog of astronomical objects called the Hubble Source Catalog. The catalog provides one-stop shopping for measurements of objects observed with NASA's Hubble Space Telescope. Hubble has amassed a rich legacy of images and other scientific data over its 25 years of exploring the universe. All of the images are stored in the computer-based Barbara A. Mikulski Archive for Space Telescopes (MAST), which astronomers use for their research. The archive is bursting with more than a million images, which contain roughly 100 million small sources ranging from distant galaxies to compact star clusters to individual stars. For astronomers, however, a major challenge is the difficulty involved with sifting through the archival gold mine to collect the data they want to analyze. The Hubble Source Catalog now allows astronomers to perform a computer search for characteristics of these sources, receiving information within seconds or minutes. View the full article
  12. Nearly 500 million miles from the Sun lies a moon orbiting Jupiter that is slightly larger than the planet Mercury and may contain more water than all of Earth's oceans. Temperatures are so cold, though, that water on the surface freezes as hard as rock and the ocean lies roughly 100 miles below the crust. Nevertheless, where there is water there could be life as we know it. Identifying liquid water on other worlds — big or small — is crucial in the search for habitable planets beyond Earth. Though the presence of an ocean on Ganymede has been long predicted based on theoretical models, NASA's Hubble Space Telescope found the best evidence for it. Hubble was used to watch aurorae glowing above the moon's icy surface. The aurorae are tied to the moon's magnetic field, which descends right down to the core of Ganymede. A saline ocean would influence the dynamics of the magnetic field as it interacts with Jupiter's own immense magnetic field, which engulfs Ganymede. Because telescopes can't look inside planets or moons, tracing the magnetic field through aurorae is a unique way to probe the interior of another world. View the full article
  13. Three-leaf clover plants abound everywhere: on lawns, in gardens, and in forests. But spotting a four-leaf clover is a rare, lucky find. Astronomers using the Hubble Space Telescope have found the equivalent of a four-leaf clover with the discovery of four images of the same supernova. The images are arranged around a giant foreground elliptical galaxy embedded in a cluster of galaxies. The arrangement forms a cross-shaped pattern called an Einstein Cross. The powerful gravity from both the elliptical galaxy and its galaxy cluster magnifies the light from the supernova behind them in an effect called gravitational lensing. The elliptical galaxy and its galaxy cluster, MACS J1149.6+2223, are 5 billion light-years away from Earth. The supernova behind it is 9.3 billion light-years away. Once the four images fade away, astronomers predict they will have a rare opportunity to watch a rerun of the supernova's appearance. Computer models of the cluster predict that another image of the stellar blast will appear within five years. Astronomers may have missed an earlier appearance of the supernova in 1995. These multiple appearances of the exploding star are due to the various paths its divided light is taking through the maze of clumpy dark matter in the galactic grouping. Each image takes a different route through the cluster and arrives at a different time, due, in part, to differences in the length of the pathways the light follows to reach Earth. View the full article
  14. Over a decade before planets were found orbiting normal stars, the astronomy world was intrigued by the discovery of a vast, edge-on, pancake-flat disk of dust and gas encircling the newborn star Beta Pictoris. It appeared to validate the hypothesis by the German philosopher Immanuel Kant, 230 years ago, that our solar system was born when planets condensed from nebular material in the plane of such a disk. (This model was independently proposed by French scholar Pierre-Simon Laplace in 1796.) Kant regarded the coplanar obits of the planets a fossil skeleton of the long-ago disintegrated disk. Though nearly two dozen circumstellar debris disks have been viewed by the Hubble Space Telescope to date, Beta Pictoris is the first and best example of what a forming young planetary system looks like. That's because it can be seen edge on, and it is the only disk to date where a planet has also been imaged. Hubble has been used to intensively study the disk for the past two decades and this latest picture – when compared to previous observations – shows that the disk particles appear to smoothly revolve around the star like a majestic carousel. Ground-based telescopes found a Jupiter-sized world embedded in the disk in 2009, and future observations may yield more planetary objects. View the full article
  15. Firing off a string of snapshots like a sports photographer at a NASCAR race, NASA's Hubble Space Telescope captured a rare look at three of Jupiter's largest moons zipping across the banded face of the gas-giant planet: Europa, Callisto, and Io. Jupiter's four largest moons can commonly be seen transiting the face of the giant planet and casting shadows onto its cloud tops. However, seeing three moons transiting the face of Jupiter at the same time is rare, occurring only once or twice a decade. Missing from the sequence, taken on January 24, 2015, is the moon Ganymede that was too far from Jupiter in angular separation to be part of the conjunction. Join Hubble Heritage Team members during the live Hubble Hangout event at 3:00 pm (EST) today (Thursday, February 5) to learn more about Jupiter's rare triple-moon conjunction. View the full article
  16. At first glance, galaxy NGC 7714 resembles a partial golden ring from an amusement park ride. This unusual structure is a river of Sun-like stars that has been pulled deep into space by the gravitational tug of a bypassing galaxy (not seen in this Hubble Space Telescope photo). Though the universe is full of such colliding galaxies that are distorted in a gravitational taffy-pull, NGC 7714 is particularly striking for the seeming fluidity of the stars along a vast arc. The near-collision between the galaxies happened at least 100 million years ago. View the full article
  17. Although NASA's Hubble Space Telescope has taken many breathtaking images of the universe, one snapshot stands out from the rest: the iconic view of the so-called "Pillars of Creation." The jaw-dropping photo, taken in 1995, revealed never-before-seen details of three giant columns of cold gas bathed in the scorching ultraviolet light from a cluster of young, massive stars in a small region of the Eagle Nebula, or M16. Though such butte-like features are common in star-forming regions, the M16 structures are by far the most photogenic and evocative. The Hubble image is so popular that it has appeared in movies and television shows, on tee-shirts and pillows, and even on a postage stamp. And now, in celebration of its 25th anniversary, Hubble has revisited the famous pillars, providing astronomers with a sharper and wider view, shown in the right-hand image. For comparison, the original 1995 Hubble image of the gaseous towers appears in the left-hand view. Streamers of gas can be seen bleeding off pillars as the intense radiation heats and evaporates it into space. Stars are being born deep inside the pillars. View the full article
  18. The largest NASA Hubble Space Telescope image ever assembled, this sweeping view of a portion of the Andromeda galaxy (M31) is the sharpest large composite image ever taken of our galactic neighbor. Though the galaxy is over 2 million light-years away, the Hubble telescope is powerful enough to resolve individual stars in a 61,000-light-year-long section of the galaxy's pancake-shaped disk. It's like photographing a beach and resolving individual grains of sand. And, there are lots of stars in this sweeping view – over 100 million, with some of them in thousands of star clusters seen embedded in the disk. This ambitious photographic cartography of the Andromeda galaxy represents a new benchmark for precision studies of large spiral galaxies which dominate the universe's population of over 100 billion galaxies. Never before have astronomers been able to see individual stars over a major portion of an external spiral galaxy. Most of the stars in the universe live inside such majestic star cities, and this is the first data that reveal populations of stars in context to their home galaxy. The panorama is the product of the Panchromatic Hubble Andromeda Treasury (PHAT) program. Images were obtained from viewing the galaxy in near-ultraviolet, visible, and near-infrared wavelengths, using the Advanced Camera for Surveys and the Wide Field Camera 3 aboard Hubble. This view shows the galaxy in its natural visible-light color, as photographed with Hubble's Advanced Camera for Surveys in red and blue filters July 2010 through October 2013. View the full article
  19. At a time when our earliest human ancestors had recently mastered walking upright, the heart of our Milky Way galaxy underwent a titanic eruption, driving gases and other material outward at 2 million miles per hour. Now, at least 2 million years later, astronomers are witnessing the aftermath of the explosion: billowing clouds of gas towering about 30,000 light-years above and below the plane of our galaxy. The enormous structure, dubbed the Fermi Bubbles, was discovered five years ago as a gamma-ray glow on the sky in the direction of the galactic center. The balloon-like features have since been observed in X-rays and radio waves. But astronomers needed NASA's Hubble Space Telescope to measure for the first time the velocity and composition of the mystery lobes. They now seek to calculate the mass of the material being blown out of our galaxy, which could lead them to determine the outburst's cause from several competing scenarios. The graphic shows how Hubble probed the light from a distant quasar to analyze the outflow. The quasar's light passed through one of the bubbles. Imprinted on that light is information about the outflow's speed, composition, and eventually mass. View the full article
  20. It's the stuff of a science fiction movie: a mysterious form of energy that is pulling the universe apart at an ever-faster rate. Astronomers around the world are befuddled and are marshaling the world's most powerful telescopes in their search for clues to understanding what this "dark force" could be. Who knows how the story will end? This script was not written by Hollywood writers but by two teams of astronomers, including scientists at the Space Telescope Science Institute in Baltimore, Maryland. And now Hollywood has taken notice. The two groups received the $3 million Breakthrough Prize in Fundamental Physics. Adam Riess of the Space Telescope Science Institute and Johns Hopkins University in Baltimore, Maryland, Saul Perlmutter of the University of California, Berkeley, and Brian P. Schmidt of the Australian National University accepted the award on behalf of their teams at an Academy Awards-style ceremony in California. Riess (at far right in the photo) and Schmidt led the High-Z Supernova Team, Perlmutter the Supernova Cosmology Project. Other Institute scientists sharing the prize are Susana Deustua, Nino Panagia, and Andy Fruchter of the Supernova Cosmology team (seen left to right in the photo) and Ron Gilliland of the High-Z team. View the full article
  21. The American Association for the Advancement of Science (AAAS) Council has elected Margaret Meixner of the Space Telescope Science Institute (STScI) and 401 other AAAS members as Fellows of AAAS. Election as an AAAS Fellow is an honor bestowed upon AAAS members by their peers. Meixner is cited by the AAAS for her "leadership in the area of infrared instrumentation for astronomy, both from the ground and from space and for distinguished service in science team management for the James Webb Space Telescope." The new Fellows will be formally announced in the AAAS News & Notes section of the journal Science on November 28, 2014. The new Fellows will be presented with an official certificate and a gold and blue (representing science and engineering, respectively) rosette pin on February 14, 2015, from 8:00 a.m. to 10:00 a.m. at the AAAS Fellows Forum during the 2015 AAAS Annual Meeting in San Jose, California. View the full article
  22. The Association of Universities for Research in Astronomy (AURA) announced today that Dr. Matt Mountain, Director of the Space Telescope Science Institute in Baltimore, Maryland, will become AURA President beginning March 1, 2015. Mountain will succeed William S. Smith who served as President since 2000. In announcing the selection, the Chair of the AURA Board of Directors, Dr. Richard Green, said, "AURA is heading into an exciting period, and Matt has enormous experience in large program and large facility management in ground- and space-based organizations. This will be a great asset for AURA as we complete construction on the Daniel K. Inoue Solar Telescope, the Large Synoptic Survey Telescope, and the James Webb Space Telescope." In accepting this appointment, Mountain said, "I am looking forward to working with the Board and our impressive Centers on the many challenging, yet exciting opportunities for astronomy, our community, and AURA in the coming years. I believe AURA has a great future, and I feel especially privileged to be chosen to help craft that future in partnership with the AURA Board." Mountain served as Gemini Observatory Director from 1999 to 2005. In 2005 he was then appointed Director of the Space Telescope Science Institute, where he has served until the present. STScI is the science operations center for the Hubble Space Telescope for NASA, and is preparing for the science and mission operations of the Webb telescope. View the full article
  23. The Space Telescope Science Institute (STScI) in Baltimore, Maryland, has appointed Dr. Roeland van der Marel to lead its work on a proposed NASA space telescope that will provide images as sharp as the Hubble Space Telescope, but over a hundred times larger area. The space observatory, called the Wide-Field Infrared Survey Telescope-Astrophysics Focused Telescope Assets (WFIRST-AFTA), is being studied for launch in the mid-2020s, pending program approval by NASA. The telescope will be used to probe the distribution of dark matter and the characteristics of dark energy, measure the abundance and characteristics of planets orbiting other stars, and will provide observations and surveys to study many other astrophysical subjects. STScI is presently the science operations center for the Hubble Space Telescope and the science and mission operations center for the James Webb Space Telescope, scheduled for launch in 2018. Van der Marel joined the STScI staff in 1997. He is also an adjunct professor in the Department of Physics and Astronomy at the Johns Hopkins University in Baltimore, Maryland. He is an expert on black holes and the structure of galaxies. View the full article
  24. Hubble has uncovered young, massive, compact galaxies whose raucous star-making parties are ending early. The firestorm of star birth has blasted out most of the remaining gaseous fuel needed to make future generations of stars. Now the party's over for these gas-starved galaxies, and they are on track to possibly becoming so-called "red and dead galaxies," composed only of aging stars. An analysis of 12 merging galaxies is suggesting that energy from the star-birthing frenzy created powerful winds that are blowing out the gas, squelching future generations of stars. This activity occurred when the universe was half its current age of 13.7 billion years. The graphic illustrates how a vibrant, star-forming galaxy quickly transforms into a sedate galaxy composed of old stars. The scenario begins when two galaxies merge (Panel 1), funneling a large amount of gas into the central region. The gas compresses, sparking a firestorm of star birth, which blows out most of the remaining star-forming gas (Panel 2). Devoid of its fuel, the galaxy settles into a quiet existence, composed of aging stars (Panel 3). View the full article
  25. Over the past few years, astronomers have found an incredible diversity in the architecture of exoplanetary systems, as well as the planets themselves. A survey using the sharp view of the Hubble Space Telescope has uncovered a similar diversity in the debris systems that coincide with the formation of exoplanets. These circumstellar dusty disks are likely generated by collisions between objects left over from planet formation around stars. The survey's results suggest that there is some sort of interdependence between a planet and the accompanying debris system. View the full article
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