The Hubble telescope's infrared camera has uncovered a collision between two spiral galaxies in the heart of the peculiar galaxy called Arp 220. The collision has provided the spark for a burst of star formation.
Hubble's infrared vision has captured bright knots of stars forming in the heart of Arp 220. The bright, crescent, moon-shaped object is a remnant core of one of the colliding galaxies. The core is a cluster of 1 billion stars. The core's half-moon shape suggests that its bottom half is obscured by a disk of dust about 300 light-years across. This disk is embedded in the core and may be swirling around a black hole. The core of the other colliding galaxy is the bright round object to the left of the crescent, moon-shaped object. Both cores are about 1,200 light-years apart and are orbiting each other.
Fireworks Near a Black Hole in the Core of Seyfert Galaxy NGC 4151
The Hubble telescope's imaging spectrograph simultaneously records, in unprecedented detail, the velocities of hundreds of gas knots streaming at hundreds of thousands of miles per hour from the nucleus of NGC 4151, thought to house a super-massive black hole. This is the first time the velocity structure in the heart of this object, or similar objects, has been mapped so vividly this close to its central black hole.
The heart of NGC 4151 was captured in visible light in the upper left picture. In the other images, Hubble's imaging spectrograph has zeroed in on the galaxy's active central region. The Hubble data clearly show that the some material in the galaxy's hub is rapidly moving towards us, while other matter rapidly receding from us. This information is strong evidence for the existence of a black hole, an extremely compact, dense object that feeds on material swirling around it.
Hubble Reveals Invisible High-Speed Collision around Supernova 1987A
The highest velocity material expelled in a cataclysmic, stellar explosion 10 years ago has been detected for the first time by the Hubble telescope's imaging spectrograph.
The top image, taken with Hubble's visible-light camera, shows the orange-red rings surrounding Supernova 1987A in the Large Magellanic Cloud. The glowing debris of the supernova explosion, which occurred in February 1987, is at the center of the inner ring. The small, white square indicates the location of the imaging spectrograph aperture. The Hubble data in the middle panel [and a schematic representation in the bottom panel] shows the presence of glowing hydrogen expanding at a speed of 33 million mph (15,000 kilometers per second) coming from an extended area inside the inner ring.
Gamma-Ray Bursts Common To Normal Galaxies? Hubble Data Offer New Clues and Puzzles
Nature's most powerful explosions, gamma-ray bursts, occur among the normal stellar population inside galaxies scattered across the universe. The energy released in such a titanic explosion, which can last from a fraction of a second to a few hundred seconds, is equal to all of the Sun's energy generated over its 10-billion-year lifetime.
Here is the visible glow from one such burst, GRB 970228. This Hubble telescope picture is the first visible-light view ever taken that links a gamma-ray burst with a potential host galaxy. This observation provides strong supporting evidence that gamma-ray bursts are cosmological- they originate in distant galaxies across the universe. The arrow points to the fireball, which is the white blob immediately to the upper left of center. Immediately to the lower right of center is an extended object (roughly resembling an "E") and interpreted to be the host galaxy where the gamma-ray burst is embedded.
The visible fireball from a titanic explosion in deep space, called a gamma-ray burst, blazes in the center of this image, taken with the Hubble telescope's imaging spectrograph.
The burst occurred on May 8, 1997, and Hubble observations to acquire the fading fireball were made on June 2. No accompanying object, such as a host galaxy, can be found near the burst. This result adds to the puzzlement over the source of these enigmatic explosions, because a previous Hubble picture of the visible glow from another gamma-ray burst identified a potential host galaxy.
The Hubble telescope has snapped a picture of a 400-kilometer-high (250-mile-high) plume of gas and dust from a volcanic eruption on Io, Jupiter's large, innermost moon.
Io was passing in front of Jupiter when Hubble took this image. The plume appears as an orange patch just off the edge of Io [at eight o'clock], against the blue background of Jupiter's clouds. Io's volcanic eruptions blast material hundreds of kilometers into space in giant plumes of gas and dust. In this image, material must have been blown out of the volcano at more than 2,000 mph to form a plume of this size, which is the largest yet seen on Io.
Hubble's Look At Mars Shows Canyon Dust Storm, Cloudy Conditions For Pathfinder Landing
Hubble telescope pictures of Mars, taken June 27, 1997 in preparation for the July 4 landing of the Pathfinder spacecraft, show a dust storm churning through the deep canyons of Valles Marineris, just 600 miles (1,000 kilometers) south of the Pathfinder spacecraft landing site.
Astronomers also report the presence of patchy cirrus clouds over the landing site and very thick clouds to the north. Because there are so many clouds (related to low temperatures in the atmosphere causing water vapor to freeze), the dust will probably stay confined to the canyons, they conclude. The green cross on the bottom picture identifies the Pathfinder landing site.
Hubble Sees Rapid Weather Changes On Mars, New Dust Activity
Astronomers using the Hubble telescope to track weather on Mars and how it might affect the Pathfinder landing site in Ares Vallis report that a large dust storm seen south of the site only 12 days earlier has dissipated. However, a new dust storm has appeared in the polar region, about 1,200 miles (2,000 kilometers) due north of the landing site.
The Hubble researchers conclude that Pathfinder landed during a period when large changes in the regional distributions of dust and clouds were taking place on Mars. The green cross on the bottom picture identifies the Pathfinder landing site.
World's Most Powerful Telescopes Team Up With a Lens in Nature to Discover Farthest Galaxy in the Universe
An international team of astronomers has discovered the most distant galaxy in the universe to date. They found it by combining the unique sharpness of the Hubble telescope with the light-collecting power of the W. M. Keck Telescopes- with an added boost from a gravitational lens in space.
The results show the young galaxy is as far as 13 billion light-years from Earth, based on an estimated age for the universe of approximately 14 billion years. The Hubble picture at left shows the young galaxy as a red crescent to the lower right of center. The galaxy's image is brightened, magnified, and smeared into this arc-shape by the gravitational influence of an intervening galaxy cluster, which acts like a gigantic lens. The image at upper right is a close-up of the "gravitationally lensed" galaxy. In the picture at lower right, astronomers have "unsmeared" the galaxy, revealing the galaxy's normal appearance.
Although the giant star Mira has been known for about 400 years, astronomers have had to wait for the Hubble telescope to provide the first ultraviolet-light images of the extended atmosphere of the cool red giant star and its nearby, hot companion.
By giving astronomers a clear view of the individual members of this system, Hubble has provided valuable insights into other types of double-star systems where the stars are so close they interact with one another. In ultraviolet light, Hubble resolves a small, hook-like appendage extending from Mira and pointing towards the smaller companion. This material could be gravitationally drawn towards Mira's mate.
Hubble Reveals Huge Crater on the Surface of the Asteroid Vesta
Astronomers have used the Hubble Space telescope to discover a giant impact crater on the asteroid Vesta. The crater is a link in a chain of events thought responsible for forming a distinctive class of tiny asteroids as well as some meteorites that have reached the Earth.
The giant crater is 285 miles across, which is nearly equal to Vesta's 330-mile diameter. If Earth had a crater of proportional size, it would fill the Pacific Ocean basin. Astronomers had predicted the existence of one or more large craters, reasoning that if Vesta is the true "parent body" of some smaller asteroids then it should have the wound of a major impact that was catastrophic enough to knock off big chunks. In this Hubble picture of Vesta, a "nub" at the bottom of the asteroid is suggestive of a catastrophic impact.
Probing the heart of the active galaxy NGC 6251, the Hubble telescope has provided a never-before-seen view of a warped disk or ring of dust caught in a blazing torrent of ultraviolet light from a suspected massive black hole.
This discovery suggests that the environments around black holes may be more varied than thought previously and may provide a new link in the evolution of black holes in the centers of galaxies. This composite picture of the galaxy's core of the galaxy combines visible- and ultraviolet-light observations. While the visible-light image shows a dark dust disk, the ultraviolet image [color-coded blue] reveals a bright feature along one side of the disk. Because Hubble sees ultraviolet light reflected from only one side of the disk, astronomers conclude it must be warped like the brim of a hat. The bright white spot at the image's center is light from the vicinity of the black hole, which is illuminating the disk.
Hubble Stays on Trail of Fading Gamma-Ray Burst Fireball, Results Point to Extragalactic Origin
Hubble telescope observations of the ever-fading fireball from one of the universe's most mysterious phenomena ? a gamma-ray burst ? is reinforcing the emerging view that these titanic explosions happen far away in other galaxies and are among the most spectacularly energetic events in the universe.
In this Hubble image of the gamma-ray burst's visible-light component, the fireball has faded to 1/500th its brightness since its discovery in March 1997 by ground-based telescopes. Hubble continues to clearly see the fireball [center of picture] and a cloud of material surrounding it, which is considered to be its host galaxy.
Hubble Watches the Red Planet as Mars Global Surveyor Begins Aerobraking
This Hubble telescope picture of Mars was taken Sept. 12, 1997, one day after the arrival of the Mars Global Surveyor (MGS) spacecraft and only five hours before the beginning of autumn in the Martian Northern Hemisphere.
This Hubble picture was taken in support of the MGS mission. Hubble is monitoring Martian weather conditions, such as large dust storms, during the early phases of the spacecraft's aerobraking.
Nova eruptions by dying stars were thought to be simple, predictable acts of violence. Astronomers could point a telescope at the most recently exploded novae and see an expanding bubble of gaseous debris around each star.
Scientists using the Hubble telescope, however, were surprised to find that some nova outbursts may not produce smooth shells of gas, but thousands of gaseous blobs, each the size of our solar system. In this Hubble picture of the nova T Pyxidis, the shells of gas ejected by the star are actually more than 2,000 gaseous blobs packed into an area that is 1 light-year across.
Astronomers using the Hubble telescope have taken their first direct look in visible light at a lone neutron star. This view offers a unique opportunity to pinpoint the star's size and to narrow theories about the composition and structure of this bizarre class of gravitationally collapsed, burned out stars.
The Hubble results show that the star [marked by white arrow] is very hot and can be no larger than 16.8 miles (28 kilometers) across. These findings prove that the object must be a neutron star, for no other known type of object can be this hot, small, and dim.
Hubble Identifies What May Be the Most Luminous Star Known
Astronomers using the Hubble telescope have identified what may be the most luminous star known ? a celestial mammoth that releases up to 10 million times the power of the Sun and is big enough to fill the diameter of Earth's orbit. The star [center of image] unleashes as much energy in six seconds as our Sun does in one year.
The image, taken in infrared light, also reveals a bright nebula [magenta-colored material], created by extremely massive stellar eruptions. The nebula is so big (4 light-years) that it would nearly span the distance from the Sun to Alpha Centauri, the nearest star to Earth's solar system.
The Hubble telescope has uncovered over 1,000 bright; young star clusters bursting to life in a brief, intense, brilliant "fireworks show" at the heart of a pair of colliding galaxies.
The picture on the left provides a sweeping view of the two galaxies, called the Antennae. The green shape pinpoints Hubble's view. Hubble's close-up view
provides a detailed look at the "fireworks" at the center of this wreck. The respective cores of the twin galaxies are the orange blobs, left and right of center, crisscrossed by filaments of dark dust. A wide band of chaotic dust stretches between the cores of the two galaxies. The sweeping spiral-like patterns, traced by bright blue star clusters, are the result of a firestorm of star birth that was triggered by the collision.
Astronomers have long been mystified by observations of a few hot, bright, apparently young stars residing in well-established communities where most of their neighbors are much older.
With the help of the Hubble telescope, astronomers now have evidence that may eventually help solve the 45-year-old mystery of how these enigmatic stars, called blue stragglers, were formed. For the first time, astronomers have confirmed that a blue straggler in the core of a globular cluster (a very dense community of stars) is a massive, rapidly rotating star that is spinning 75 times faster than the Sun. This finding provides proof that blue stragglers are created by collisions or other intimate encounters in an overcrowded cluster core. A ground-based telescope image
shows the crowded core of the globular cluster 47 Tucanae, which is teeming with blue stragglers. Peering into the heart of the cluster's brilliant core, Hubble separated the dense clump of stars into many individual stars
Using the Hubble telescope's visible-light camera, astronomers for the first time this century have detected clouds in the Northern Hemisphere of Uranus. The snapshots show banded structure and multiple clouds. Using these images, astronomers plan to measure the wind speeds in the Northern Hemisphere for the first time.
The clouds can be seen along the planet's right edge [the bright dots]. Another cloud [faint white dot] is barely visible near the bottom of the blue band. The clouds are almost as large as continents on Earth, such as Europe.
