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In fifteen years of operation, the Chandra X-ray Observatory has given us a view of the Universe that is largely hidden from telescopes sensitive only to visible light.

Chandra has captured galaxy clusters - the largest gravitationally bound objects in the Universe - in the process of forming, and provided the best evidence yet that the cosmos is dominated by a mysterious substance called dark matter. Chandra has observed gas circling near a black hole's event horizon. The atoms of this gas are doomed to destruction by the extreme gravity of the black hole.

Most of the elements necessary for life are forged inside stars and blasted into interstellar space by supernovas. Chandra has tracked these elements with unprecedented accuracy. Young stars are crackling with X-ray flares and other energetic radiation. By monitoring clusters of young stars, Chandra can give us a sense of what our young Sun was like when life was evolving on Earth.

Chandra: Taking us on a unique voyage into the big, bad and beautiful Universe.

  • On July 23, 1999, the Chandra X-ray Observatory was launched into orbit aboard the Space Shuttle Columbia. Chandra is one of NASA's four "Great Observatories," along with the Hubble Space Telescope, the Spitzer Space Telescope, and the Compton Gamma Ray Observatory.
  • This year marks the 15th anniversary of NASA's Chandra X-ray Observatory successful launch into space and science operations. Chandra has three major parts: (1) the X-ray telescope, whose mirrors focus X-rays from celestial objects; (2) the science instruments which record the X-rays so that X-ray images can be produced and analyzed; and (3) the spacecraft, which provides the environment necessary for the telescope and the instruments to work.
  • Chandra follows an unusual orbit that was achieved after deployment by a built-in propulsion system that boosted the observatory to a high Earth orbit. This orbit, which has the shape of an ellipse, takes the spacecraft more than a third of the way to the Moon before returning to its closest approach to the Earth of 16,000 kilometers (9,942 miles).
  • In its first decade and a half of exploration, Chandra has expanded our view of the Universe with its unrivaled ability to create high-resolution X-ray images of cosmic phenomena: X-ray sources produced by matter circling only a few miles from a black hole, whirling, super-dense neutron stars expelling fingers and rings of extremely high energy particles, a look at the insides of an exploded star, and clouds of hot degree gas in galaxy clusters millions of light years across. None of this could be observed without an X-ray telescope.
  • Chandra. Seeing the Universe in a whole new light.