Solar Maximum Mission

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This article is about the spacecraft. For the solar phenomenon, see Solar maximum, for other uses, see SMM (disambiguation)

SMM satellite

Capturing the Solar Maximum Mission satellite from STS-41-C

The Solar Maximum Mission satellite (or SolarMax) was designed to investigate solar phenomenon, particularly solar flares. It was launched on February 14, 1980.

Although not unique in this endeavor, the SMM was notable in that its useful life compared with similar spacecraft was significantly increased by the direct intervention of a manned space mission. In 1984 the Space Shuttle Challenger intercepted it, maneuvering the SMM into the shuttle's payload bay for maintenance and repairs. SMM had been fitted with a shuttle "grapple fixture" so that the shuttle's robot arm could grab it in anticipation of possible repairs. The mission is depicted in the 1985 IMAX movie The Dream Is Alive.

Significantly, the SMM's ACRIM instrument package showed that, contrary to expectations, the Sun is actually brighter during the sunspot cycle maximum (when the greatest number of dark 'sunspots' appear). This is because sunspots are surrounded by bright features called faculae, which more than cancel the darkening effect of the sunspot.

The Solar Maximum Mission ended on December 2, 1989, when the spacecraft re-entered the atmosphere and burned up.

The major scientific findings from SMM are presented in several review articles in the Monograph edited by Strong et al. (1999).

The Solar Maximum Mission satellite during 1987-1989 discovered 10 sungrazing comets.^[1]

[edit] References

^ JPL comet catalogue

Strong, Keith T.; Saba, Julia L. R.; Haisch, Bernhard M.; Schmelz, Joan T. (1999) The many faces of the sun : a summary of the results from NASA's Solar Maximum Mission. Springer