The Japan Aerospace Exploration Agency (JAXA) found that communication with the X-ray Astronomy Satellite "Hitomi" (ASTRO-H), launched on February 17, 2016 (JST), failed from the start of its operation originally scheduled at 16:40, Saturday March 26 (JST). Up to now, JAXA has not been able to figure out the state of health of the satellite.
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JAXA | Communication anomaly of X-ray Astronomy Satellite "Hitomi" (ASTRO-H)