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Chandra X-Ray Observatory

Phase: Operating

Launch Date: July 23, 1999

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Program(s):Physics of the Cosmos

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NASA's Chandra X-ray Observatory was launched and deployed by Space Shuttle Columbia on July 23, 1999. It was the most sophisticated X-ray observatory to date when launched. Since the Earth's atmosphere absorbs the vast majority of X-rays, they are not detectable from ground-based telescopes, requiring a space-based telescope to make these observations. Chandra has answered and will continue to answer many questions about the high-energy universe, enabling scientists to pose new questions about the universe.

G299.2-2.9 belongs to a class of supernovas called Type Ia. This debris field was left over when a star exploded about 4,500 years ago. In the image, red, green, and blue represent low, medium, and high-energy X-rays, respectively. Infrared data show the stars in the Chandra field of view.

Credit: X-ray: NASA/CXC/U.Texas/S.Post et al, Infrared: 2MASS/UMass/IPAC-Caltech/NASA/NSF

Chandra is designed to observe X-rays from high-energy regions of the universe, such as the remnants of exploded stars. Chandra’s instruments have approximately fifty times better resolution (pixel area fifty or more times smaller) than the High Resolution Imager on the ROSAT Observatory, the best predecessor. Chandra images reveal new details about phenomena in our Universe. Scientists can now see rings and jets in the region around a pulsar, like the one in the Crab Nebula supernova remnant. This level of detail can provide valuable information for understanding how the pulsar transmits energy to the nebula as a whole.

NASA's premier X-ray observatory was named the Chandra X-ray Observatory in honor of the late Indian-American Nobel laureate, Subrahmanyan Chandrasekhar (pronounced: su/bra/mon'/yon chandra/say/kar). Known to the world as Chandra (which means "moon" or "luminous" in Sanskrit), he was widely regarded as one of the foremost astrophysicists of the twentieth century.

Science Highlights:

  • Found strong evidence that dark matter exists by observing collisions of galaxy clusters
  • Discovered powerful outbursts from supermassive black holes in galaxies
  • Independently confirmed that the expansion of the universe is accelerating
  • Discovered the youngest supernova remnant and the youngest X-ray binary in our galaxy
  • Observed dramatic flares and powerful X-ray emission from stars, tracking their effects on planet-forming disks or orbiting planets
  • Spotted the first X-ray emission seen from the supermassive black hole, Sagittarius A*, at the center of the Milky Way
  • Discovered a new type of black hole in galaxy M82, a mid-mass black hole
  • Sound waves from violent activity were observed in the Perseus Cluster around a supermassive black hole
  • Identified that nearly all stars on the main sequence emit X-rays

Last updated: April 1, 2015

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