spacetoday.net: Contamination affecting Chandra instrument

Posted: Fri, Nov 7, 2003, 8:22 AM ET (1322 GMT)
Chandra X-Ray Observatory illustration (NASA/MSFC)

A layer of contamination is reducing the effectiveness of one instrument on NASA's Chandra X-Ray Observatory, New Scientist magazine reported this week. In an article published in the November 8 issue of the British magazine, project officials confirm that a thin layer of grease had built up on a filter located in front of the spacecraft's Advanced CCD Imaging Spectrometer (ACIS). The layer has the effect of reducing the amount of low-energy x-rays reaching the instrument, as if a gas cloud existed in space between the x-ray source and the telescope, absorbing the x-rays. Project engineers are considering a "bakeout" where the filter is heated to remove the grease, although there is concern the procedure could make the problem worse. That bakeout, if carried out, would not take place until April or May of 2004.