|Back to News Center Home|
Chandra Images Provide New Vision
Images released today from NASA's Chandra X-ray Observatory reveal previously unobserved features in the remnants of three different supernova explosions.
Two of the remnants, G21.5-0.9 and PSR 0540-69, show details of the prodigious production of energetic particles by a rapidly rotating, highly magnetized neutron star, as well as the enormous shell structures produced by the explosions. The image of the third remnant, E0102-72, reveals puzzling spoke-like structures in its interior.
G21.5-0.9, in the constellation of Scutum, is about 16,000 light years from Earth. One light year equals six trillion miles. Chandra's image shows a bright nebula surrounded by a much larger diffuse cloud.
Inside the inner nebula is a bright central source that is thought to be a rapidly rotating, highly magnetized neutron star. A rotating neutron star acts like a powerful generator, creating intense electric voltages that accelerate electrons to speeds close to the velocity of light. The total output of this generator is greater than a thousand suns. The fluffy appearance of the central nebula is thought to be due to magnetic field lines which constrain the motions of the high energy electrons.
"It's a remarkable image," said Dr. Patrick Slane of the
Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass. "Neither the inner core nor the outer shell has ever been seen before."
"It is as though we have a set of Russian dolls, with structures embedded within structures," said Professor Gordon Garmire of Pennsylvania State University in University Park, Pa., and principal investigator of Chandra's Charge-Coupled Device X-ray camera, used to make the image.
NASAs project scientist, Dr. Martin Weisskopf of the Marshall Space Flight Center in Huntsville, Ala., said, "Chandras capability to provide surprises and insights continues!"
The existence of a rotating neutron star, or pulsar, in the center of G21.5-0.9 is inferred from the appearance of the nebula and the energy distribution of X-rays and radio waves from the nebula. This distribution, called non-thermal radiation, is characteristic of radiation produced by high energy electrons in a magnetic field.
A previously known pulsar is observed directly in the Chandra image of PSR 0540-69. This pulsar, located in a 180,000 light-year-distant satellite galaxy to our Milky Way, emits pulses of radio, optical and X -ray energy at a rate of 50 per second. These pulses, which come from a neutron star rotating at this incredible rate, comprise only a few percent of the total energy output of the neutron star powerhouse.
"The Chandra image gives us a much better idea of how this energy source works," said Dr. Stephen Murray, principal investigator for the High Resolution Camera, the X-ray camera used to make this image. "You can see X-ray jets blasting out from the pulsar in both directions."
The third Chandra image is of E0102-72, in the Small Magellanic Cloud, another satellite galaxy of the Milky Way. This galaxy is 190,000 light years from Earth. This object, like G21.5-0.9 and PSR 0540-69, is believed to have resulted from the explosion of a massive star several thousand years ago. Stretching across 40 light years of space, the multi-million-degree source resembles a flaming cosmic wheel.
"Chandra's gallery of supernova remnants is giving us a lot to think about," said Dr. Fred Seward of Harvard-Smithsonian, who, with his colleagues, discovered E0102-72 and PSR 0540-69 by using a Chandra predecessor, NASAs Einstein Observatory, over a decade ago. "We're seeing many things we thought should be there, and many others that we never expected. It's great!"
To follow Chandra's progress, visit the Chandra News Web site at:
NASA's Marshall Space Flight Center in Huntsville, Ala., manages the Chandra X-ray Observatory for the Office of Space Science, NASA Headquarters, Washington, D.C. The Smithsonian Astrophysical Observatory's Chandra X-ray Center in Cambridge, Mass., manages the Chandra science program and controls the observatory for NASA. TRW Space and Electronics Group of Redondo Beach, Calif., leads the contractor team that built Chandra.
Note to Editors / News Directors: Interviews and photos supporting this release are available to media representatives by contacting Tim Tyson of the Marshall Media Relations Department at (256) 544-0034. For an electronic version of this release, digital images or more information, visit Marshall's News Center on the Web at:
Members of the media: To receive Marshall releases by e-mail instead of fax, please e-mail email@example.com. Include the name of your media outlet, your title, mailing address, phone and fax numbers, and the headline of this news release.