The colorful, intricate shapes in these NASA Hubble Space Telescope images reveal how the glowing gas ejected by dying Sun-like stars evolves dramatically over time. These gaseous clouds, called planetary nebulae, are created when stars in the last stages of life cast off their outer layers of material into space. The snapshots of He 2-47, NGC 5315, IC 4593, and NGC 5307 were taken with Hubble's Wide Field Planetary Camera 2 in February 2007.
Astronomy textbooks typically present galaxies as staid, solitary, and majestic island worlds of glittering stars. But galaxies have a dynamical side. They have close encounters that sometimes end in grand mergers and overflowing sites of new star birth as the colliding galaxies morph into wondrous new shapes. Today, in celebration of the Hubble Space Telescope's 18th launch anniversary, 59 views of colliding galaxies constitute the largest collection of Hubble images ever released to the public. This new Hubble atlas dramatically illustrates how galaxy collisions produce a remarkable variety of intricate structures in never-before-seen detail.
What's My Age? Mystery Star Cluster Has 3 Different Birthdays
Imagine having three clocks in your house, each chiming at a different time. Astronomers have found the equivalent of three out-of-sync "clocks" in the ancient open star cluster NGC 6791. The dilemma may fundamentally challenge the way astronomers estimate cluster ages, researchers said.
Using NASA's Hubble Space Telescope to study the dimmest stars in the cluster, astronomers uncovered three different age groups. Two of the populations are burned-out stars called white dwarfs. One group of these low-wattage stellar remnants (red circles) appears to be 6 billion years old, another (blue circles) appears to be 4 billion years old. The ages are out of sync with those of the cluster's normal stars, which are 8 billion years old.
This sequence of Hubble Space Telescope images offers an unprecedented view of a planetary game of Pac-Man among three red spots clustered together in Jupiter's atmosphere. The time series shows the passage of the "Red Spot Jr." in a band of clouds below (south) of the Great Red Spot (GRS). "Red Spot Jr." first appeared on Jupiter in early 2006 when a previously white storm turned red. This is the second time, since turning red, it has skirted past its big brother apparently unscathed. But this is not the fate of "baby red spot," which is in the same latitudinal band as the GRS. This new red spot first appeared earlier this year. The baby red spot gets ever closer to the GRS in this picture sequence until it is caught up in the anticyclonic spin of the GRS. In the final image the baby spot is deformed and pale in color and has been spun to the right (east) of the GRS. These three natural-color Jupiter images were made from data acquired on May 15, June 28, and July 8, 2008, by the Wide Field Planetary Camera 2 (WFPC2).
Globular Clusters Tell Tale of Star Formation in Nearby Galaxy Metropolis
Globular star clusters, dense bunches of hundreds of thousands of stars, have some of the oldest surviving stars in the universe. A new study of globular clusters outside our Milky Way Galaxy has found evidence that these hardy pioneers are more likely to form in dense areas, where star birth occurs at a rapid rate, instead of uniformly from galaxy to galaxy. Astronomers used NASA's Hubble Space Telescope to identify over 11,000 globular clusters in the Virgo cluster of galaxies. Most are older than 5 billion years. The sharp vision of Hubble's Advanced Camera for Surveys resolved the star clusters in 100 galaxies of various sizes, shapes, and brightnesses, even in faint, dwarf galaxies. The images in this photo show four members of the Virgo cluster of galaxies. Comprised of over 2,000 galaxies, the Virgo cluster is the nearest large galaxy cluster to Earth, located about 54 million light-years away.
Hubble Unveils a Deep Sea of Small and Faint Early Galaxies
Scientists have long suspected there must be a hidden population of small, faint galaxies that were responsible during the universe's early years for producing a majority of stars now present in the cosmos. At last Hubble has found them in the deepest ultraviolet-light exposures made of the early universe. This underlying population is 100 times more abundant in the universe than their more massive cousins that were detected previously.
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.
Hubble Identifies a Long-Sought Population of Comets Beyond Neptune
The Hubble telescope has detected a long-sought population of comets dwelling at the icy fringe of the solar system. The observation, which is the astronomical equivalent to finding the proverbial needle-in-a-haystack, bolsters proof for a primordial comet reservoir just beyond Neptune. The circles pinpoint one of the candidate Kuiper belt objects. The dotted lines represent a possible orbit that this Kuiper belt comet is following.
Based on the Hubble observations, a team of astronomers estimate that the belt contains at least 200 million comets, which have remained essentially unchanged since the birth of the solar system 4.5 billion years ago.
Hubble Photo Gallery of Jupiter's Galilean Satellites
Located approximately a half billion miles away, the moons are so small that, in visible light, they appear as fuzzy disks in the largest ground-based telescopes. Hubble can resolve surface details seen previously only by the Voyager space probes in the early 1980s. While the Voyager probes provided close-up snapshots of the satellites, Hubble can now follow changes on the moons and reveal other characteristics at ultraviolet and near-infrared wavelengths.
This pair of images of Jupiter's volcanic moon Io, taken with the Hubble telescope, shows the surprising emergence of a 200-mile-wide, yellowish-white feature near the center of the moon's disk [photo on the right]. This represents a more dramatic change in 16 months than any seen over the previous 15 years, say researchers. They suggest the spot may be a new class of transient feature on the moon. For comparison the photo on the left was taken in March 1994, before the spot emerged. The photo indicates that Io's surface had undergone only subtle changes since it was last seen close-up by the Voyager 2 probe in 1979.
Hubble Views the Galileo Probe Entry Site on Jupiter
This Hubble telescope image of Jupiter
was taken when the giant planet was 534 million miles (854 million kilometers) from Earth. The arrow points to the predicted site at which the Galileo probe will enter Jupiter's atmosphere on December 7, 1995. At this latitude, the eastward winds have speeds of about 250 mph (110 meters per second). The white oval to the north of the probe site drifts westward at 13 mph (6 meters per second), rolling in the winds, which increase sharply toward the equator.
The four enlarged Hubble images of Jupiter's equatorial region
show clouds sweeping across the predicted Galileo probe entry site, which is at the exact center of each frame. A tiny white dot marks the predicted entry site.
Panoramic Hubble Picture Surveys Star Birth, Proto-Planetary Systems in the Great Orion Nebula
This spectacular color panorama of the center of the Orion Nebula is one of the largest pictures ever assembled from individual images taken with the Hubble telescope.
The seemingly infinite tapestry of rich detail revealed by Hubble shows a churning, turbulent star factory set within a maelstrom of flowing, luminescent gas. Though this 2.5-light-year-wide view is a small portion of the entire nebula, it includes a star cluster and almost all of the light from the bright glowing clouds of gas that make up the nebula.
Hubble Space Telescope evokes a new sense of awe and wonder about the infinite richness of our universe in dramatic, unprecedented pictures of celestial objects. Like a traveler sharing their best snapshots, we present a selection of Hubble's most spectacular images (1990-1995).
Astronomers Announce First Clear Evidence of a Brown Dwarf
Astronomers have made the first unambiguous detection of an elusive type of object known as a brown dwarf.
The evidence consists of observations from 60-inch and 200-inch telescopes on Mount Palomar, and a confirmatory image from the Hubble telescope. The brown dwarf, called Gliese 229B (GL229B), is a small companion to the cool, red star Gliese 229, located 19 light-years from Earth in the constellation Lepus. Estimated to be 20 to 50 times the mass of Jupiter, GL229B is too massive and hot to be classified as a planet, but too small and cool to shine like a star. At least 100,000 times dimmer than Earth's Sun, the brown dwarf is the faintest object ever seen orbiting another star.
Hubble Finds a New Black Hole - and Unexpected New Mysteries
Confirming the presence of yet another super-massive black hole in the universe, astronomers using the Hubble telescope have found unexpected mysteries. The black hole and an 800-light-year-wide, spiral-shaped disk of dust fueling it are slightly offset from the center of the host galaxy, NGC 4261.
Prior to Hubble observations, astronomers did not think dust was common in elliptical galaxies like NGC 4261, which were thought to have stopped making stars long ago due to the absence of the requisite raw materials: gas and dust. However, Hubble is showing that dust and dust disks are common in the centers of elliptical galaxies.
Hubble's Deepest View of the Universe Unveils Bewildering Galaxies across Billions of Years
One peek into a small part of the sky, one giant leap back in time. The Hubble telescope has provided mankind's deepest, most detailed visible view of the universe.
Representing a narrow "keyhole" view stretching to the visible horizon of the universe, the Hubble Deep Field image covers a speck of the sky only about the width of a dime 75 feet away. Though the field is a very small sample of the heavens, it is considered representative of the typical distribution of galaxies in space, because the universe, statistically, looks largely the same in all directions. Gazing into this small field, Hubble uncovered a bewildering assortment of at least 1,500galaxies at various stages of evolution.
A vibrant celestial photo album of some of NASA Hubble Space Telescope's most stunning views of the universe is being unveiled today on the Internet. Called the Hubble Heritage Program, this technicolor gallery is being assembled by a team of astronomers at Hubble's science operations center, the Space Telescope Science Institute in Baltimore, Md. The four images released today are (top row, left to right) spiral galaxy NGC 7742, Saturn, and (bottom row, left to right) the Sagittarius Star Cloud and the Bubble Nebula.
Natural Lenses in Space Stretch Hubble's View of the Universe
A Hubble telescope survey of the sky has uncovered exotic patterns, rings, arcs, and crosses that are all mirages produced by a gravitational lens, nature's equivalent of having a giant magnifying glass in space.
A gravitational lens is created when the gravity of a massive foreground object, such as a galaxy or a black hole, bends the light coming from a far more distant galaxy directly behind it. This "gravitational muscle" focuses the light to give multiple or distorted images of the background object as seen by the observer. Shown are 10 examples from the survey.
Astronomers using the Hubble telescope have discovered an enormous cyclonic storm system raging in the northern polar regions of the planet Mars. Nearly four times the size of the state of Texas, the storm is composed of water ice clouds like storm systems on Earth, rather than dust typically found in Martian storms.
The system is similar to so-called "spiral" storms observed more than 20 years ago by NASA's Viking Orbiter spacecraft, but it is nearly three times as gigantic as the largest previously detected Martian spiral storm system. The storm is nearly 1,100 miles across in the east-west direction and 900 miles in the north-south direction. The eye of the storm is nearly 200 miles in diameter. Each of these pictures illustrates the breadth of this immense storm.
A Butterfly-Shaped "Papillon" Nebula Yields Secrets of Massive Star Birth
Here is a Hubble telescope view of a turbulent cauldron of star birth called N159, which is taking place 170,000 light-years away in our satellite galaxy, the Large Magellanic Cloud. Torrential stellar winds from hot, newborn, massive stars within the nebula sculpt ridges, arcs, and filaments in the vast cloud, which is over 150 light-years across.
A rare type of compact, illuminated "blob" is resolved for the first time to be a butterfly-shaped or "Papillon" (French for "butterfly") Nebula, buried in the center of the maelstrom of glowing gases and dark dust. The unprecedented details of the structure of the Papillon, itself less than 2 light-years in size, are seen in the inset picture.
