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Diffuse X-ray Spectrometer

Phase: Past

Launch Date: January 13, 1993

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The Diffuse X-ray Spectrometer (DXS) was a single experiment shuttle payload designed to fly on multiple missions. The primary objective of the DXS payload was to obtain measurements on the diffuse soft X-ray background radiation in the Milky Way Galaxy. DXS flew as a shuttle cargo bay attached payload using the Hitchhiker avionics and Shuttle Payload of Opportunity Carrier (SPOC) hardware, which provided support systems for power, command, and telemetry to the DXS instruments. DXS was first flown on the STS 54 mission.

The Diffuse X-Ray Spectrometer (DXS) consisted of 2 large area Bragg crystal spectrometers that covered the energy range 0.15 - 0.28 keV. When DXS was flown as an attached payload of the Space Shuttle (STS-54), the two spectrometers were mounted on opposite sides of the shuttle cargo bay as part of the GSFC Shuttle Payload of Opportunity Carrier system, part of the Hitchhiker shuttle series.

The experiment was designed primarily to detect the diffuse X-ray background. During the 80 orbit nights of DXS data collection time during the shuttle mission, the orbiter was oriented such that the DXS detectors repeatedly scanned the same arc on the sky - within 10° of the galactic plane from longitudes 150°-300°.

Science Highlights

  • Obtained the first-ever high resolution spectra of the diffuse soft X-ray background in the energy band from 0.15 to 0.28 keV (4.3-8.4 nm).

Last updated: May 28, 2015

Related Links
  • STS-54 info -
  • More about DXS -