Jupiter's Upper Atmospheric Winds Revealed in Ultraviolet Images by Hubble Telescope
These four NASA Hubble Space Telescope images of Jupiter, as seen in visible (violet) and far-ultraviolet (UV) wavelengths, show the remarkable spreading of the clouds of smoke and dust thrown into the atmosphere after the impacts of the fragments of comet P/Shoemaker-Levy 9. These dark regions provide the only information ever obtained on the wind direction and speed in Jupiter's upper atmosphere. (More at Hubble Site)
Hubble Sees Auroral Emission Arcs Following the k Impact
In the Jupiter campaign, scientists wanted to see how the comet collisions affected the Jovian aurorae, rapid and irregular displays of colorful light in a planet's night sky caused by the leakage of charged particles from the magnetosphere into the atmosphere. Following the impacts, some of the resulting debris became electrically charged and traveled along Jupiter's magnetic field lines and created new aurorae in Jupiter's northern hemisphere, as shown in this image. Scientists had never before observed aurorae this far south of where aurorae are typically seen in Jupiter's northern hemisphere. (More at Hubble Site)
Month Long Evolution of the D/G Jupiter Impact Sites from Comet P/Shoemaker-Levy 9
This series of snapshots, taken with NASA's Hubble Space Telescope, shows evolution of the comet P/Shoemaker-Levy 9 impact region called the D/G complex. This feature was produced by two nuclei of comet P/Shoemaker-Levy 9 that collided with Jupiter on 17 and 18 July 1994, respectively, and was later modified again by the impact of the S fragment on 21 July 1994. (More at Hubble Site)
Jupiter Mapping Traces Changes in Comet P/Shoemaker-Levy 9 Impact Sites
This series of color-composite maps of Jupiter, assembled from images taken with NASA's Hubble Space Telescope, allows astronomers to trace changes in the dark impact sites that resulted from the July 1994 impact of comet P/Shoemaker-Levy 9 with the giant planet. Through computer image processing, researchers "peel" the atmosphere of Jupiter off its globe and spread it flat into a map. These cylindrical projections show the entire atmosphere of Jupiter in one map. The HST's images show clearly that dark material produced in the comet explosion has continued to spread in Jupiter's atmosphere. However, the "band" of dark material is still clumpy, which suggests that the major impact sites are still localized and, so, can still be identified. (More at Hubble Site)
Hubble Observations Shed New Light on Jupiter Collision
In the weeks following comet P/Shoemaker-Levy 9's spectacular July collision with Jupiter, a team of Hubble telescope astronomers has pored over imaging and spectroscopic data gleaned during the interplanetary bombardment. Their initial findings, combined with results from other space-borne and ground-based telescopes, shed new light on Jupiter's atmospheric winds, its immense magnetic field, the mysterious dark debris from the impacts, and the composition of the doomed comet itself.
These four Hubble telescope images of Jupiter, as seen in visible and far-ultraviolet wavelengths, show the remarkable dispersion of the clouds of smoke and dust thrown into the atmosphere after chunks of the comet slammed into Jupiter's southern region. These dark regions provide the only information ever obtained on the wind direction and speed in Jupiter's upper atmosphere. (More at Hubble Site)
Tale of Two Clusters Yields Secrets of Star Birth in the Early Universe
The Hubble telescope has provided new insights into how stars may have formed many billions of years ago in the early universe. Hubble observations of a pair of star clusters suggest they might be linked through stellar evolution processes.
The pair of clusters is 166,000 light-years from Earth in the Large Magellanic Cloud in the southern constellation Doradus. The clusters are unusually close together for being distinct and separate objects, suggesting that they might be evolutionary relatives. (More at Hubble Site)
Hubble Rules Out a Leading Explanation for Dark Matter
Astronomers have ruled out the possibility that red dwarf stars constitute the invisible matter, called dark matter, believed to account for more than 90 percent of the universe's mass.
Until now, the dim, small stars were considered ideal candidates for dark matter. Whatever dark matter is, its gravitational pull ultimately will determine whether the universe will expand forever or will someday collapse. Picking a region in our Milky Way Galaxy, astronomers predicted that Hubble should have spied 38 red dwarf stars if this class of objects harbored most of the dark matter. The diamond-shaped symbols in the left-hand image illustrate what scientists expected to see. Instead, they saw no stars. (More at Hubble Site)
Hubble Space Telescope Measures Precise Distance to the Most Remote Galaxy Yet
Astronomers using the Hubble telescope have announced the most accurate distance measurement yet to the remote galaxy M100, located in the Virgo cluster of galaxies.
This measurement will help provide a precise calculation of the expansion rate of the universe, called the Hubble Constant, which is crucial to determining the age and size of the universe. They calculated the distance - 56 million light-years - by measuring the brightness of several Cepheid variable stars in the galaxy. Cepheid variables are a class of pulsating star used as "milepost markers" to calculate the distance to nearby galaxies. The bottom image shows a region of M100. This Hubble telescope image is a close-up of a region of the galaxy M100. The top three frames, taken over several weeks, reveal the rhythmic changes in brightness of a Cepheid variable. (More at Hubble Site)
Hubble Observes the Moons and Rings of the Planet Uranus
This Hubble telescope snapshot of the planet Uranus reveals the planet's rings, at least five of the inner moons, and bright clouds in the Southern Hemisphere. Hubble allows astronomers to revisit the planet at a level of detail not possible since the Voyager 2 spacecraft flew by the planet briefly, nearly a decade ago.
This picture is a combination of images showing the motion of the inner moons. Each inner moon appears as a string of three dots. Thanks to Hubble's capabilities, astronomers will be able to precisely determine the moons' orbits. (More at Hubble Site)
Astronomers Discover Nearby Spiral Galaxy Hidden Behind the Milky Way
An international team of astronomers has uncovered a galaxy in our own cosmic back yard. Though only ten million light-years away (or five times the distance of the Andromeda galaxy - closest assemblage of stars to our Milky Way Galaxy), this newly discovered city of more than 100 billion stars has gone undetected previously because it is hidden from view behind our Milky Way galaxy. (More at Hubble Site)
UA Scientist & Team Discover Surface Features Cover Titan
Scientists for the first time have made images of the surface of Saturn's giant, haze-shrouded moon, Titan. They mapped light and dark features over the surface of the satellite during nearly a complete 16-day rotation. One prominent bright area they discovered is a surface feature 2,500 miles across, about the size of the continent of Australia.
Titan, which is larger than Mercury and slightly smaller than Mars, is the only body in the solar system, other than Earth, that may have oceans and rainfall on its surface. The oceans and rain are composed of ethane-methane rather than water. (More at Hubble Site)
Observes the Lost Ancestors to Our Milky Way Galaxy
This NASA Hubble Space Telescope (HST) image of the central portion of a remote cluster of galaxies (CL 0939+4713) as it looked when the universe was two-thirds of its present age. Hubble's high resolution allows astronomers to study, for the first time, the shapes of galaxies as they were long ago.
The Space Telescope pictures are sharp enough to distinguish between various forms of spiral galaxies. Most of the spiral, or disk, galaxies have odd features, suggesting they were easily distorted within the environment of the rich cluster. Hubble reveals a number of mysterious "fragments" of galaxies interspersed through the cluster. (More at Hubble Site)
Hubble Identifies Primeval Galaxies, Uncovers New Clues to the Universe's Evolution
Astronomers using the Hubble telescope as a "time machine" have obtained the clearest views yet of distant galaxies that existed when the universe was a fraction of its current age.
A series of remarkable pictures, spanning the life history of the cosmos, are providing the first clues to the life history of galaxies. The Hubble results suggest that elliptical galaxies developed remarkably quickly into their present shapes. However, spiral galaxies that existed in large clusters evolved over a much longer period - the majority being built and then torn apart by dynamic processes in a restless universe. These pictures of faraway galaxies, located 5 to 10 billion light-years from Earth, illustrate the findings. (More at Hubble Site)
This Hubble telescope picture of Saturn captures a rare storm that appears as a white arrowhead-shaped feature near the planet's equator. An upwelling of warmer air, similar to a terrestrial thunderhead, generates the storm.
The east-west extent of this storm is equal to the diameter of the Earth (about 7,900 miles). Hubble provides new details about the effects of Saturn's prevailing winds on the storm. These winds shape a dark "wedge" that eats into the left side of the bright central cloud. The new image shows that the storm's motion and size have changed little since its discovery in September 1994. (More at Hubble Site)
Hubble Finds One of the Smallest Stars in the Universe
The Hubble telescope's crisp vision has captured a first-time view of one of the smallest stars in our Milky Way Galaxy. Called Gliese 623b or Gl623b, the diminutive star [right of center] is 10 times less massive than the Sun and 60,000 times fainter. (If it were as far away as the Sun, it would be only eight times brighter than the full Moon).
Located 25 light-years from Earth in the constellation Hercules, Gl623b is the smaller component of a double-star system, where the separation between the two members is only twice the distance between Earth and the Sun (approximately 200 million miles). The small star completes one orbit around its larger companion every four years. (More at Hubble Site)
Hubble Discovers Powerful Laser Beamed from Chaotic Star
Darth Vader take heart. Astronomers have discovered a powerful ultraviolet laser beam, several times brighter than our Sun, shooting toward Earth from a super-hot "death star."
The observations, made with the Hubble telescope, have identified a gas cloud that acts as a natural ultraviolet laser near the huge, unstable star called Eta Carinae ? one of the most massive and energetic stars in our Milky Way Galaxy. The interstellar laser may result from Eta Carinae's violently chaotic eruptions, in which it blasts parts of itself out into space, like an interstellar geyser. This illustration depicts a gas cloud
, which acts as a natural ultraviolet laser near Eta Carinae
Hubble Views a Starry Ring World Born in a Head-On Collision
A rare and spectacular head-on collision between two galaxies appears in this Hubble telescope picture of the Cartwheel Galaxy, located 500 million light-years from Earth in the constellation Sculptor.
The striking ring-like feature is a direct result of a smaller intruder galaxy - possibly one of two objects to the right of the ring - that careened through the core [close-up image at lower left] of the host galaxy. Like a rock tossed into a lake, the collision sent a ripple of energy into space, plowing gas and dust in front of it. Expanding at 200,000 mph, this cosmic tsunami leaves in its wake a firestorm of new star creation. Hubble resolves bright blue knots that are gigantic clusters of newborn stars [close-up image at upper left] and immense loops and bubbles blown into space by exploding stars (called supernovae) going off like a string of firecrackers. (More at Hubble Site)
Red Dwarf Dynamo Raises Puzzle over Interiors of Lowest Mass Stars
The Hubble telescope has uncovered surprising evidence that powerful magnetic fields may exist around the lowest mass stars in the universe, which barely have enough nuclear fuel to burn as stars.
Hubble detected a high-temperature outburst, called a flare, on the surface of the extremely small, cool red dwarf star Van Biesbroeck 10, also known as Gliese 752B. Stellar flares are caused by intense, twisted magnetic fields that accelerate and contain gases that are much hotter than a star's surface. The illustration demonstrates the complex nature of this star. (More at Hubble Site)
This Hubble telescope image shows one of the most complex planetary nebulae ever seen, NGC 6543, nicknamed the "Cat's Eye Nebula." Hubble reveals surprisingly intricate structures including concentric gas shells, jets of high-speed gas, and unusual shock-induced knots of gas. Estimated to be 1,000 years old, the nebula is a visual "fossil record" of the dynamics and late evolution of a dying star.
A preliminary interpretation suggests that the object might be a double-star system. The dynamical effects of two stars orbiting one another most easily explains the intricate structures, which are much more complicated than features seen in most planetary nebulae. The two stars are too close together to be individually resolved by Hubble and instead appear as a single point of light at the center of the nebula. (More at Hubble Site)
Astronomers report today that new observations from the Hubble telescope challenge 30 years of scientific theory about quasars, the most energetic objects in the universe. Hubble images show, to the surprise of researchers, that the environment surrounding quasars is far more violent and complex than expected, providing evidence of galactic collisions and mergers.
This Hubble picture provides evidence for a merger between a quasar and a companion galaxy. The bright central object is the quasar itself, located several billion light-years away. The two wisps on the left of the central object are remnants of a bright galaxy that have been disrupted by the mutual gravitational attraction between the quasar and the companion galaxy. (More at Hubble Site)
