Tuesday, May 23, 2006

Gravitational Lens SDSS J1004+4112

Credit: ESA, NASA, K. Sharon (Tel Aviv University) and E. Ofek (Caltech)

NASA's Hubble Space Telescope has captured the first-ever picture of a group of five star-like images of a single distant quasar.

The multiple-image effect seen in the Hubble picture is produced by a process called gravitational lensing, in which the gravitational field of a massive object — in this case, a cluster of galaxies — bends and amplifies light from an object — in this case, a quasar — farther behind it.

Wednesday, May 10, 2006

Comet 73P /Schwassman-Wachmann 3

Credit: NASA/JPL-Caltech/W. Reach (SSC/Caltech)

This infrared image from NASA's Spitzer Space Telescope shows the broken Comet 73P/Schwassman-Wachmann 3 skimming along a trail of debris left during its multiple trips around the sun. The flame-like objects are the comet's fragments and their tails, while the dusty comet trail is the line bridging the fragments.

Comet 73P /Schwassman-Wachmann 3 began to splinter apart in 1995 during one of its voyages around the sweltering sun. Since then, the comet has continued to disintegrate into dozens of fragments, at least 36 of which can be seen here. Astronomers believe the icy comet cracked due the thermal stress from the sun.

The Spitzer image provides the best look yet at the trail of debris left in the comet's wake after its 1995 breakup. The observatory's infrared eyes were able to see the dusty comet bits and pieces, which are warmed by sunlight and glow at infrared wavelengths. This comet debris ranges in size from pebbles to large boulders. When Earth passes near this rocky trail every year, the comet rubble burns up in our atmosphere, lighting up the sky in meteor showers. In 2022, Earth is expected to cross close to the comet's trail, producing a noticeable meteor shower.

Astronomers are studying the Spitzer image for clues to the comet's composition and how it fell apart. Like NASA's Deep Impact experiment, in which a probe smashed into comet Tempel 1, the cracked Comet 73P/Schwassman-Wachmann 3 provides a perfect laboratory for studying the pristine interior of a comet.

This image was taken from May 4 to May 6 by Spitzer's Multiband Imaging Photometer, using its 24-micron wavelength channel.

Sunday, May 07, 2006

NGC 2440 - Cocoon of a New White Dwarf

Like a butterfly, a white dwarf star begins its life by casting off a cocoon that enclosed its former self. In this analogy, however, the Sun would be a catepillar and the ejected shell of gas would become the prettiest of all! In the above cocoon, the planetary nebula designated NGC 2440, contains one of the hottest white dwarf stars known. The white dwarf can be seen as the bright dot near the photo's center. Our Sun will eventually become a white dwarf butterfly, but not for another 5 billion years. The false color image was post-processed by Forrest Hamilton.

Credit: H. Bond (STScI), R. Ciardullo (PSU), WFPC2,HST,NASA

Saturday, May 06, 2006

Hubble Snaps Baby Pictures of Jupiter's "Red Spot Jr."

NASA's Hubble Space Telescope is giving astronomers their most detailed view yet of a second red spot emerging on Jupiter. For the first time in history, astronomers have witnessed the birth of a new red spot on the giant planet, which is located half a billion miles away. The storm is roughly one-half the diameter of its bigger and legendary cousin, the Great Red Spot. Researchers suggest that the new spot may be related to a possible major climate change in Jupiter's atmosphere.

Credit: NASA,ESA, A. Simon-Miller (NASA/GSFC), and I. de Pater (University of California Berkeley)