Distant cosmos comes into focus

X-ray observatory spots star remnants.

Scripps Howard News Service

WASHINGTON -- Using X-ray images captured by a new orbiting observatory, NASA scientists said Thursday they are able to see the remnants of a star that exploded more than three centuries ago and how such explosions might create the building blocks for life.

Launched from the space shuttle Columbia last month, the $1.5 billion Chandra X-ray Observatory still is testing and calibrating its instruments, which are designed to view the high-energy emissions of exploding stars, black holes, colliding galaxies and other cosmic phenomena, many of which are nearly invisible to standard telescopes that work with light.

The Chandra telescope is able to capture and assemble X-ray images from very distant points -- images nearly at the edge of the universe and 20 times fainter than any previous X-ray instrument was able to get. Its resolution ability is equivalent to that of a camera's being able to read the letters on a stop sign from a distance of 12 miles.

A second early image from the observatory shows a X-ray jets generating from a distant giant star and blasting far into space.

After removing its sunshade two weeks ago, scientists turned Chandra's telescope toward the remnants of a supernova, or explosion of a massive star, called Cassiopeia A, and immediately were rewarded with astounding images of material from the explosion being blasted into space at 10 million miles per hour. Based on earlier visual images, scientists said the supernova occurred 300 years ago.

"This blast was as bright as all the stars of our galaxy, a shimmering we can still see to some extent with telescopes, but certainly nothing close to what we're seeing from the X-ray energy," said Robert Kirshner, an astrophysicist at Harvard University. "This can even help us understand the structure of that giant star the day before it exploded."

After the blast, material crashed into surrounding matter in space, causing violent shock waves, like massive sonic booms, and created a vast, 50-million-degree bubble of X-ray-emitting gas.

"We see the collision of the debris from the exploded star with the matter around it; we see shock waves rushing into interstellar space at millions of miles per hour," said Harvey Tananbaum, director of the Smithsonian Astrophysical Observatory's Chandra X-ray Center in Cambridge, Mass.

"As a real bonus, we see for the first time a tantalizing bright point near the center of the remnant that could possibly be a collapsed star associated with the outburst," Tananbaum said.

That remnant could be a neutron star or perhaps even a super-dense black hole.

Chandra also has a special imaging spectrometer that allows it to "read" the X-rays of varying energies produced by each heavy element within the hot gas bubble.

With this information, astronomers hope to investigate how the elements necessary for life are created and spread across galaxies by exploding stars.

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