The first image shows an artist's interpretation of a planet in front of its sun. This illustration was compiled from Hubble data. NASA scientists say that this is new type of planet that seems to be a water world enshrouded by a thick, steamy atmosphere. It's smaller than Uranus but larger than Earth. Since the planet's mass and size are known, astronomers can calculate the density, of only about 2 grams per cubic centimeter. Water has a density of 1 gram per cubic centimeter, while Earth's average density is 5.5 grams per cubic centimeter. Theorists expect that GJ1214b formed farther out from its star, where water ice was plentiful, and migrated inward early in the system's history. In the process, it would have passed through the star's habitable zone, where surface temperatures would be similar to Earth's. How long it lingered there is unknown. GJ1214b is located in the direction of the constellation Ophiuchus, and just 40 light-years from Earth.
Using NASA's Hubble Space Telescope, astronomers have solved a longstanding mystery on the type of star that caused a supernova in a nearby galaxy. Based on previous observations from ground-based telescopes, astronomers knew that a kind of supernova called a Type Ia created a remnant named SNR 0509-67.5, which lies 170,000 light-years away in the Large Magellanic Cloud galaxy. The type of system that leads to this kind of supernova explosion has had various proposed solutions. All these solutions involve a white dwarf star that somehow increases in mass to the highest limit. Astronomers failed to find any companion star near the center of the remnant, and this rules out all but one solution, so the only remaining possibility is that this supernova came from a pair of white dwarfs in close orbit.
This Hubble image centers on the 100-million-solar-mass black hole at the hub of the neighboring spiral galaxy M31, or the Andromeda galaxy, one of the few galaxies outside the Milky Way visible to the naked eye and the only other giant galaxy in our Local Group. This is the sharpest visible-light image ever made of the nucleus of an external galaxy. The closest region around the black hole center where light can still escape is too small to be seen, but it lies near the middle of a compact cluster of blue stars at the center of the image.Our Milky Way Galaxy and Andromeda are moving toward each other and someday will merge.
The bipolar star-forming region, S106 , looks like a soaring, celestial snow angel. The outstretched "wings" of the nebula record the contrasting imprint of heat and motion against the backdrop of a colder medium. Twin lobes of super-hot gas, glowing blue in this image, stretch outward from the central star. This hot gas creates the "wings" of our angel. A ring of dust and gas orbiting the star acts like a belt, cinching the expanding nebula into an "hourglass" shape.
A giant cosmic necklace glows brightly in this NASA Hubble Space Telescope image. The object, aptly named the Necklace Nebula, is a recently discovered planetary nebula, the glowing remains of an ordinary, Sun-like star. The nebula consists of a bright ring, measuring 12 trillion miles across, dotted with dense, bright knots of gas that resemble diamonds in a necklace. The knots glow brightly due to absorption of ultraviolet light from the central stars. The Necklace Nebula is located 15,000 light-years away in the constellation Sagitta (the Arrow). In this composite image
Astronomers using NASA's Hubble Space Telescope are witnessing the unprecedented transition of a supernova to a supernova remnant, where light from an exploding star in a neighboring galaxy, the Large Magellanic Cloud, reached Earth in February 1987. Named Supernova 1987A, it was the closest supernova explosion witnessed in almost 400 years. The supernova's close proximity to Earth has allowed astronomers to study it in detail as it evolves. Now, the supernova debris, which has faded over the years, is brightening. This means that a different power source has begun to light the debris. The debris of SN 1987A is beginning to impact the surrounding ring, creating powerful shock waves that generate X-rays observed with NASA's Chandra X-ray Observatory. Those X-rays are illuminating the supernova debris and shock heating is making it glow in visible light.
To celebrate the 21st anniversary of the Hubble Space Telescope's deployment into space, astronomers pointed Hubble's eye at an especially photogenic pair of interacting galaxies called Arp 273. The larger of the spiral galaxies has a disk that is distorted into a rose-like shape by the gravitational tidal pull of the companion galaxy below it. Hubble was launched April 24, 1990, aboard Discovery's STS-31 mission.
Hubble Space Telescope took advantage of a rare opportunity to record Saturn when its rings were edge-on, allowing scientists to see the nearly symmetrical light show at both of the giant planet's poles. It takes Saturn almost thirty years to orbit the Sun, with the opportunity to image both of its poles occurring only twice during that time.
Hubble has caught Jupiter's moon Ganymede playing a game of "peek-a-boo." In this crisp Hubble image, Ganymede is shown just before it ducks behind the giant planet. This color photo was made from three images that show Jupiter and Ganymede in close to natural colors.
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 Jupiter 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.
This Hubble image shows five spots – one colored white, one blue, and three black – are scattered across the upper half of the planet. Closer inspection reveals that these spots are actually a rare alignment of three of Jupiter's largest moons – Io, Ganymede, and Callisto – across the planet's face. In this image, the telltale signatures of this alignment are the shadows [the three black circles] cast by the moons. Io's shadow is located just above center and to the left; Ganymede's on the planet's left edge; and Callisto's near the right edge. Only two of the moons, however, are visible in this image. Io is the white circle in the center of the image, and Ganymede is the blue circle at upper right. Callisto is out of the image and to the right.
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