Hubble Spies Shells of Sparkling Stars Around Quasar
What has appeared as a mild-mannered elliptical galaxy in previous studies is revealing its wild side in new images taken with NASA's Hubble Space Telescope. The Hubble photos show shells of stars around a bright quasar, known as MC2 1635+119, which dominates the center of the galaxy. The shells' presence indicates a titanic clash with another galaxy in the relatively recent past. The collision also is funneling gas into the galaxy's center and is feeding a supermassive black hole. The accretion onto the black hole is the source of the quasar's energy. This observation supports the idea that at least some quasars are born from interactions between galaxies.
Compact Galaxies in Early Universe Pack a Big Punch
Imagine receiving an announcement touting the birth of a baby 20 inches long and weighing 180 pounds. After reading this puzzling message, you would immediately think the baby's weight was a misprint. Astronomers looking at galaxies in the universe's distant past received a similar perplexing announcement when they found nine young, compact galaxies, each weighing in at 200 billion times the mass of the Sun. The galaxies, each only 5,000 light-years across, are a fraction of the size of today's grownup galaxies but contain approximately the same number of stars. Each galaxy could fit inside the central hub of our Milky Way Galaxy. Astronomers used NASA's Hubble Space Telescope and the W.M. Keck Observatory on Mauna Kea, Hawaii, to study the galaxies as they existed 11 billion years ago, when the universe was less than 3 billion years old.
In what's beginning to look like a case of planetary measles, a third red spot has appeared alongside its cousins - the Great Red Spot and Red Spot Jr. - in the turbulent Jovian atmosphere. This third red spot, which is a fraction of the size of the two other features, lies to the west of the Great Red Spot in the same latitude band of clouds. The visible-light images were taken on May 9 and 10 with Hubble's Wide Field and Planetary Camera 2.
Hubble Uncovers an Unusual Stellar Progenitor to a Supernova
Astronomers have detailed theories about what type of stars self-destruct in titanic supernova explosions. However, it would be useful to test stellar theory by actually seeing what a doomed star looked like before it blew apart. The problem is that a supernova blast pretty much eradicates all evidence of what the progenitor star was. Like a surveillance camera photographing the scene of a crime before it happened, the Hubble Space Telescope has a priceless archival photo of the galaxy that contains a picture of the supernova progenitor star as it appeared eight years before it exploded. The progenitor was comparatively easy to find because it was one of the brightest stars in the host galaxy. But the discovery has only further confounded supernova mysteries. The progenitor star belongs to a class of luminous blue variable stars that are not expected to explode at such an early stage of their existence.
The most crowded collision of galaxy clusters has been identified by combining information from three different telescopes. This result gives scientists a chance to learn what happens when some of the largest objects in the universe go at each other in a cosmic free-for-all. Using data from NASA's Chandra X-ray Observatory, Hubble Space Telescope, and the Keck Observatory in Hawaii, astronomers were able to determine the three-dimensional geometry and motion in the system MACS J0717.5+3745 (or MACS J0717, for short), located about 5.4 billion light-years from Earth.
Hubble Celebrates Its 19th Anniversary with a "Fountain of Youth"
Over the past 19 years Hubble has taken dozens of exotic pictures of galaxies going "bump in the night" as they collide with each other and have a variety of close encounters of the galactic kind. Just when you thought these interactions couldn't look any stranger, this image of a trio of galaxies, called Arp 194, looks like one of the galaxies has sprung a leak. The bright blue streamer is really a stretched spiral arm full of newborn blue stars. This typically happens when two galaxies interact and gravitationally tug at each other.
Resembling a pair of owl eyes, the two nuclei of the colliding galaxies can be seen in the process of merging at the upper left. The blue bridge looks like it connects to a third galaxy. In reality the galaxy is in the background and not connected at all. Hubble's sharp view allows astronomers to try and visually sort out what are foreground and background objects when galaxies, superficially, appear to overlap. This picture was issued to celebrate the 19th anniversary of the launch of the Hubble Space Telescope aboard the space shuttle Discovery in 1990. During the past 19 years Hubble has made more than 880,000 observations and snapped over 570,000 images of 29,000 celestial objects.
NASA's Hubble Celebrates 21st Anniversary with "Rose" of Galaxies
To celebrate the 21st anniversary of the Hubble Space Telescope's deployment into space, astronomers at the Space Telescope Science Institute in Baltimore, Md., pointed Hubble's eye at an especially photogenic pair of interacting galaxies called Arp 273. The larger of the spiral galaxies, known as UGC 1810, has a disk that is distorted into a rose-like shape by the gravitational tidal pull of the companion galaxy below it, known as UGC 1813. This image is a composite of Hubble Wide Field Camera 3 data taken on December 17, 2010, with three separate filters that allow a broad range of wavelengths covering the ultraviolet, blue, and red portions of the spectrum.
Hubble was launched April 24, 1990, aboard Discovery's STS-31 mission. Hubble discoveries revolutionized nearly all areas of current astronomical research from planetary science to cosmology.
Astronomers Find Elusive Planets in Decade-Old Hubble Data
In a painstaking re-analysis of Hubble Space Telescope images from 1998, astronomers have found visual evidence for two extrasolar planets that went undetected back then.
Finding these hidden gems in the Hubble archive gives astronomers an invaluable time machine for comparing much earlier planet orbital motion data to more recent observations. It also demonstrates a novel approach for planet hunting in archival Hubble data.
NASA's Hubble Confirms that Galaxies Are the Ultimate Recyclers
Galaxies learned to "go green" early in the history of the universe, continuously recycling immense volumes of hydrogen gas and heavy elements to build successive generations of stars stretching over billions of years. In other words they are more fuel efficient than any hybrid car on the road. This ongoing recycling keeps galaxies from emptying their "fuel tanks" and therefore stretches out their star-forming epoch to over 10 billion years. The catch is that those galaxies that crank up the rate of star formation can blow away their remaining fuel, essentially turning off further star-birth activity. But galaxies like our Milky Way that frugally pace the rate of star birth can go on building new stars at least one billion years into the future.
This conclusion is based on a series of Hubble Space Telescope observations that flexed the special capabilities of its comparatively new Cosmic Origins Spectrograph (COS) to detect otherwise invisible mass in the halo of our Milky Way and a sample of more than 40 other galaxies. The three studies investigated different aspects of the gas-recycling phenomenon in galaxies. The results are being published in three papers in the November 18 issue of Science magazine.
One of the most distant galaxies known, called GN-108036, dates back to 750 million years after the Big Bang that created our universe. The galaxy's light took 12.9 billion years to reach us. GN-108036 was discovered and confirmed using the Subaru telescope and the W.M. Keck Observatory. After the galaxy was discovered, astronomers looked at infrared observations of it taken by NASA's Spitzer and Hubble space telescopes.
Hubble's 22nd Anniversary Image Shows Turbulent Star-making Region
Several million young stars are vying for attention in this NASA Hubble Space Telescope image of a raucous stellar breeding ground in 30 Doradus, located in the heart of the Tarantula Nebula. 30 Doradus is the brightest star-forming region visible in a neighboring galaxy and home to the most massive stars ever seen. The nebula resides 170,000 light-years away in the Large Magellanic Cloud, a small, satellite galaxy of our Milky Way. No known star-forming region that is inside our Milky Way is as large or as prolific as 30 Doradus.
The image comprises one of the largest mosaics ever assembled from Hubble photos and includes observations taken by Hubble's Wide Field Camera 3 and Advanced Camera for Surveys. Hubble made the observations in October 2011. NASA and the Space Telescope Science Institute are releasing the image to celebrate Hubble's 22nd anniversary.
Unfortunately, stars don't have birth certificates. So, astronomers have a tough time figuring out their ages. Knowing a star's age is critical for understanding how our Milky Way galaxy built itself up over billions of years from smaller galaxies. But Jason Kalirai of the Space Telescope Science Institute and The Johns Hopkins University's Center for Astrophysical Sciences, both in Baltimore, Md., has found the next best thing to a star's birth certificate.
Using a new technique, Kalirai probed the burned-out relics of Sun-like stars, called white dwarfs, in the inner region of our Milky Way galaxy's halo. The halo is a spherical cloud of stars surrounding our galaxy's disk. Those stars, his study reveals, are 11.5 billion years old, younger than the first generation of Milky Way stars. They formed more than 2 billion years after the birth of the universe 13.7 billion years ago. Previous age estimates, based on analyzing normal stars in the inner halo, ranged from 10 billion to 14 billion years. Kalirai's study reinforces the emerging view that our galaxy's halo is composed of a layer-cake structure that formed in stages over billions of years.
Hubble and Chandra Find Evidence for Densest Galaxy in Nearby Universe
Astronomers may have found the densest galaxy in the nearby universe. The galaxy, known as M60-UCD1, is located near a massive elliptical galaxy NGC 4649, also called M60, about 54 million light-years from Earth. This composite image shows M60 and the region around it, where data from NASA's Chandra X-ray Observatory are pink and data from NASA's Hubble Space Telescope are red, green, and blue. The Chandra image shows hot gas and double stars containing black holes and neutron stars, and the Hubble image reveals stars in M60 and neighboring galaxies including M60-UCD1. The arrow points to M60-UCD1.
Packed with an extraordinary number of stars, M60-UCD1 is an "ultra-compact dwarf galaxy." It is one of the most massive galaxies of its kind, weighing 200 million times more than our Sun, based on observations with the Keck 10-meter telescope in Hawaii. Remarkably, about half of this mass is found within a radius of only about 80 light-years. This would make the density of stars about 15,000 times greater than found in Earth's neighborhood in the Milky Way, meaning that the stars are about 25 times closer.
Galaxy Found in Hubble Survey Has Farthest Confirmed Distance
A team of astronomers has discovered a galaxy that sets the current distance record for galaxies whose distance has been definitively measured by spectroscopic redshift. The galaxy is seen as it was at a time just 700 million years after the Big Bang, when the universe was only about 5 percent of its current age of 13.8 billion years. This galaxy and dozens of others were selected for follow-up observations from the approximately 100,000 galaxies discovered in the Hubble Space Telescope CANDELS survey (Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey). The team used the Keck I Telescope in Hawaii to measure the redshift of the CANDELS galaxy, designated z8_GND_5296, at 7.51. This is the highest galaxy redshift ever confirmed. The spectral redshift of galaxies is caused by the expansion of space from the Big Bang.
Hubble Witnesses an Asteroid Mysteriously Disintegrating
Though fragile comet nuclei have been seen falling apart as they near the Sun, nothing like the slow breakup of an asteroid has ever before been observed in the asteroid belt. A series of Hubble Space Telescope images shows that the fragments are drifting away from each other at a leisurely one mile per hour. This makes it unlikely that the asteroid is disintegrating because of a collision with another asteroid. A plausible explanation is that the asteroid is crumbling due to a subtle effect of sunlight. This causes the rotation rate to slowly increase until centrifugal force pulls the asteroid apart. The asteroid's remnant debris, weighing in at 200,000 tons, will in the future provide a rich source of meteoroids.
Hubble Shows Farthest Lensing Galaxy Yields Clues to Early Universe
Astronomers using NASA's Hubble Space Telescope have unexpectedly discovered the most distant cosmic magnifying glass yet, produced by a monster elliptical galaxy. The galaxy, seen here as it looked 9.6 billion years ago, is so massive that its gravity bends, magnifies, and distorts light from objects behind it, a phenomenon called gravitational lensing. In the Hubble image, the galaxy is the red object in the enlarged view at left.
The object behind the cosmic lens is a tiny spiral galaxy undergoing a rapid burst of star formation. Its light has taken 10.7 billion years to arrive here. In the Hubble image, the galaxy is seen in the enlarged view at right. Seeing this chance alignment at such a great distance from Earth is a rare find.
Hubble Sees Supernova Split into Four Images by Cosmic Lens
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.
Telescopes Team Up to Find Distant Uranus-Sized Planet Through Microlensing
The majority of planets discovered outside our solar system orbit close to their parent stars because these planets are the easiest to find. But to fully understand how distant planetary systems are put together, astronomers must conduct a census of all the planets around a star. So they need to look farther away from the star-from about the distance of Jupiter is from our sun, and beyond.
Now, astronomers using NASA's Hubble Space Telescope and the W. M. Keck Observatory in Hawaii have confirmed the existence of a Uranus-sized exoplanet orbiting far from its central star, discovered through a technique called gravitational microlensing. Microlensing occurs when a foreground star magnifies the light of a background star that momentarily aligns with it. The unique signature of the event, which is influenced by the relative motion of the stars across space, can reveal clues to the nature of the foreground star and any associated planets. Gravitational microlensing can find cold planets in long-period orbits that other methods cannot detect. This finding opens a new piece of discovery space in the extrasolar planet hunt: to uncover planets as far from their central stars as Jupiter and Saturn are from our sun.
NASA's Hubble Finds Supernovae in 'Wrong Place at Wrong Time'
What happens when you find something in the wrong place at the wrong time? That's a question astronomers have been trying to answer after finding several exploding stars outside the cozy confines of galaxies, where most stars reside. These wayward supernovae also have puzzled astronomers because they exploded billions of years before their predicted detonations. Astronomers using archived observations from several telescopes, including the Hubble Space Telescope, have developed a theory for where these doomed stars come from and how they arrived at their current homes.
According to their scenario, the supernovae were once stars in double-star systems that wandered too close to twin supermassive black holes at the core of a merging galaxy. The black-hole duo gravitationally catapulted the stars out of their home galaxies. The interaction pulled the stars closer together, which accelerated the merger between each pair. Eventually, the stars moved close enough to trigger a supernova blast.
Twenty-six candles grace NASA's Hubble Space Telescope's birthday cake this year, and now one giant space "balloon" will add to the festivities. Just in time for the 26th anniversary of Hubble's launch on April 24, 1990, the telescope has photographed an enormous, balloon-like bubble being blown into space by a super-hot, massive star. Astronomers trained the iconic telescope on this colorful feature, called the Bubble Nebula, or NGC 7635. The bubble is 7 light-years across – about one-and-a-half times the distance from our sun to its nearest stellar neighbor, Alpha Centauri. The Bubble Nebula lies 7,100 light-years from Earth in the constellation Cassiopeia.
