Yohkoh
Sign in to saveYohkoh (, 'Sunbeam'), known before launch as Solar-A, was a Solar observatory spacecraft of the Institute of Space and Astronautical Science (Japan), in collaboration with space agencies in the United States and the United Kingdom. It was launched into Earth orbit on August 30, 1991 by the M-3SII rocket from Kagoshima Space Center. It took its first soft X-ray image on 13 September 1991, 21:53:40, and movie representations of the X-ray corona over 1991-2001 are available at the Yohkoh Legacy site.
Key facts
- Spaceflight.name
- Yohkoh
- Spaceflight.names_list
- Solar-A (before launch
- Spaceflight.image
- 220px
- Spaceflight.image_caption
- Artist concept of the Japanese Yohkoh spacecraft
- Spaceflight.mission_type
- Heliophysics
- Spaceflight.operator
- ISAS / NASA / PPARC
- Spaceflight.COSPAR_ID
- 1991-062A
- Spaceflight.SATCAT
- 21694
- Spaceflight.website
- Yohkoh home page
- Spaceflight.mission_duration
- (achieved)
- Spaceflight.dimensions
- x x
- Spaceflight.launch_rocket
- Mu-3S-II
- Spaceflight.launch_site
- Kagoshima M1
- Spaceflight.disposal_type
- Spacecraft lost accidentally
- Spaceflight.last_contact
- 14 December 2001
- Spaceflight.decay_date
- 12 September 2005
- Spaceflight.orbit_reference
- Geocentric
- Spaceflight.orbit_inclination
- 31.3°
via Wikipedia infobox
Article
4 sectionsContents
- Description
- Instruments
- References
- External links
Yohkoh (, 'Sunbeam'), known before launch as Solar-A, was a Solar observatory spacecraft of the Institute of Space and Astronautical Science (Japan), in collaboration with space agencies in the United States and the United Kingdom. It was launched into Earth orbit on August 30, 1991 by the M-3SII rocket from Kagoshima Space Center. It took its first soft X-ray image on 13 September 1991, 21:53:40, and movie representations of the X-ray corona over 1991-2001 are available at the Yohkoh Legacy site.
==Description== thumb|Scale model of the Yohkoh at Noshiro, Akita|Noshiro City Children's Center The satellite was three-axis stabilized and in a near-circular orbit. It carried four instruments: a Soft X-ray Telescope (SXT), a Hard X-ray Telescope (HXT), a Bragg Crystal Spectrometer (BCS), and a Wide Band Spectrometer (WBS). About 50 MB were generated each day and stored on board by a 10.5 MB bubble memory recorder. thumb|Sun as viewed by the Soft X-Ray Telescope (SXT) onboard the orbiting Yohkoh satellite (8 May 1992). Because SXT utilized a charge-coupled device (CCD) as its readout device, perhaps being the first X-ray astronomical telescope to do so, its "data cube" of images was both extensive and convenient, and it revealed much interesting detail about the behavior of the solar corona. Previous solar soft X-ray observations, such as those of Skylab, had been restricted to film as a readout device. Yohkoh therefore returned many novel scientific results, especially regarding solar flares and other forms of magnetic activity. thumb|Sun as viewed by the Soft X-Ray Telescope (SXT) with the thin Al filter onboard the Yohkoh spacecraft (7 July 1999). The mission ended after more than ten years of successful observation when it went into its "safehold" mode during an annular eclipse on 14 December 2001, 20:58:33 and the spacecraft lost lock on the Sun. Operational mistakes and other flaws combined in such a way that its solar panels could no longer charge the batteries, which drained irreversibly; several other solar eclipses had successfully been observed.