Japanese satellite Hitomi suffers permanent failure

Nature : On 28 April the Japan Aerospace Exploration Agency announced that it had lost control over its flagship astronomical satellite Hitomi. Despite a successful launch on 17 February, the satellite began experiencing problems within the first few weeks. The source of the difficulty has been traced to its star tracker system, one of several systems on board designed to orient the satellite in space. The star tracker was found to malfunction every time the satellite passed through a certain area over Earth called the South Atlantic Anomaly , where the belts of radiation encircling the planet dip closest to its surface and thus expose satellites to higher-than-normal radiation levels. On 26 March, while Hitomi was passing through that area, a glitch with the star tracker initiated a series of failures with the satellite’s gyroscopes. Hitomi spun out of control, and its solar panels and other components broke off. Although the loss of Hitomi represents a significant blow for x-ray astronomy, before it failed scientists were able to make one important astronomical observation, which could yield enough data for a series of papers.