Coldest ever space instrument set to fly

The coldest instrument ever to fly in space is set to launch aboard a Japanese X-ray observatory called Astro-E2 on Wednesday. The instrument, which has suffered several previous setbacks, will study some of the most energetic phenomena in the universe.
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This sensitive task requires Astro-E2’s main instrument, the X-Ray Spectrometer (XRS), to be cooled to just 0.06 degrees above absolute zero. This will allow it to detect extremely small changes in photon energies - representing a 10-fold improvement in sensitivity compared to existing detectors.