On 2016 February 17 (Japan Standard Time 17:45), JAXA's ASTRO-H satellite, poised to be the 6th Japanese X-ray Astronomy Mission, was launched successfully by the HIIA rocket No.30. Under the leadership of Prof. Tadayuki Takahashi of the JAXA/Institute of Space and Astronautical Science, the spacecraft and its onboard instruments were developed over the last decade by a large international collaboration consisting of more than 30 domestic Universities/Institutions, many industries, and teams from 8 foreign countries. After the satellite successfully achieved the scheduled near-Earth orbit, it was named "Hitomi", or "Iris" in Japanese, as it will serve as a novel X-ray iris to watch the Hot and Violent universe.
"Hitomi" carries two types of X-ray telescopes and 4 kinds of X-ray/soft gamma-ray detectors that are coaligned and operated simultaneously to define a broad energy coverage from 0.3 keV to 600 keV. Among the detectors, the Soft X-ray Spectrometer, developed under an extensive Japan-US collaboration, deserves a particular notice; utilizing an extremely low-temperature condition realized by a cryogenic system, it affords more than an order-of-magnitude better energy resolution than has ever been achieved in orbit using non-dispersive techniques. Succeeding its predecessor "Suzaku", "Hitomi" will observe various kinds of X-ray emitting objects, including galaxy clusters, black holes with a wide range of masses, supernova remnants, neutron stars of different types, active stars, and our Galactic Center. These observations will be performed mainly through international proposals.
Kazuo Makishima, Institute of Physical and Chemical Research (RIKEN)