Japan Aerospace Exploration Agency ISAS SitemapJAXA Sitemap

TOP > Our Enterprises > Missions > X-ray Astronomy ASCA (ASTRO-D)


Mission Profile

Name (pre-launch in parentheses) ASCA (ASTRO-D)
International Designation Code 1993-011A
Objectives Precise X-ray observation of various bodies in the universe and X-ray exploration of the deepest region of the universe such as galaxy clusters
Launch Date February 20, 1993
Location Kagoshima Space Center (Uchinoura)
Launch Vehicle
Configuration Weight 420 kg
Shape 4.7m high cylinder
Two folding-type (three-fold) solar paddles

[Click image for enlargement]
Orbit Altitude Perigee 525 km, Apogee 615 km
Inclination 31°
Type of Orbit Near circular
Period 96 min.
Scientific Instruments
  1. X-ray Telescope (XRT)
  2. X-ray CCD camera (SIS, Solid-State Imaging Spectrometer)
  3. Gas-Imaging Spectrometer (GIS)
End of Operation March 2, 2001
Reentered Date March 2, 2001
Operation After launch, the Extendable Optical Bench (EOB), equivalent to the telescope's lens tube, was successfully extended. Observation then began and continued smoothly. In July 2000, however, the earth atmosphere expanded due to solar activity at that time. The satellite experienced friction caused by the thin atmosphere and started spinning. Finally, ASCA was unable to continue observation. Satellite operation continued with minimal functions, until, at around 14:20 on March 2, 2001, it entered the atmosphere and vanished.
Results The successful results included the first imaging of X-ray objects by the scintillation proportional counter on March 17, 1993, and observation of X-rays from the supernova SN1993J recently discovered in the M81 galaxy.