NASA News

July 28, 1999

Chandra X-ray Observatory Activation Begins

HUNTSVILLE, AL, July 27 -- NASA reports that all systems are continuing to function as expected aboard the Chandra X-ray Observatory, which was deployed this week by the Space Shuttle Columbia crew. Activation of the world's most powerful X-ray telescope, from the Chandra Operations Control Center in Cambridge, MA, continued to go well as the observatory began its fourth day in orbit.

The Chandra X-ray Observatory, managed by NASA's Marshall Space Flight Center, is designed to allow scientists to obtain X-ray images and spectra of violent, high temperature events and objects to help them better understand the structure and evolution of our universe. Chandra has a resolving power of -0.5 arc seconds and will be able to detect sources more than 20 times fainter than those observed by any previous X-ray telescope. It is also designed to study some quasars as they were 10 billion years ago. In addition, NASA says that Chandra will be able to study particles up to the last millisecond before they are sucked inside black holes.

Chandra's orbital activation and checkout period is expected to last about two months. This week, the flight operations team in Cambridge has been focusing on activities associated with the initial activation of Chandra's Advanced CCD Imaging Spectrometer -- a combination spectrometer and camera housed in the observatory's science instrument module.

Termperature in the focal plane area of the instrument was increased from -120^oC to -50^oC on Monday, July 26; at 8:39 p.m. EDT, a large vent valve was opened to allow off-gassing of any condensation or particles that may have accumulated on the instrument's detectors prior to launch. Temperature inside the instrument was re-cooled to -120^o at the conclusion of this partial "bake-out" period. The valve will remain open for the duration of Chandra's five-year mission.