Chandra X-ray Observatory

Update: 99-156

During the past 12 hours the Chandra X-ray Observatory flight operations team in Cambridge, Mass., has concentrated its efforts on initial activation of Chandra's science instruments.

Activation and checkout of the observatory has been progressing so well that some activities, planned for later in the mission, have been moved forward on the timeline. These include the opening of a protective door in one of the science instruments and activation activities associated with another of the instruments.

At 2:33 p.m. EDT controllers reported the successful opening of a hinged door that covered Chandra's High Resolution Camera. This is the first step in activating the instrument for its science mission. The camera, which is located in the observatory's science instrument module at the narrow end of the telescope, will record high-resolution images of x-ray producing celestial objects.

The team also commanded and monitored another routine Earth Sensor Scan, a series of activities that enables controllers to analyze Chandra's attitude and update it if needed.

Over the next 12 hours the Chandra's Advanced Charge-coupled Device Imaging Spectrometer, also housed in the science instrument module, will begin a partial bake-out period and the opening of its large vent valve. The bake-out is expected to last several hours in order to raise the temperature within the instrument's focal plane from minus-120 degrees C to minus-50 degrees C. The valve is expected open approximately midway through the bake-out. This activity will allow for out-gassing of any condensation or particles that may have gathered on the instrument's focal plane.

Editor's Note: NASA's Marshall Space Flight Center in Huntsville, Ala., manages the Chandra X-ray Observatory for NASA's Office of Space Science, NASA Headquarters, Washington, D.C. The Smithsonian Astrophysical Observatory 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.