Data & Observations

Solar Maximum Mission (SMM)

The Solar Maximum Mission (SMM) observatory was launched by a Delta rocket on February 14, 1980, from Cape Canaveral, Florida. SMM's payload consisted of eight instruments that provided broad spectral coverage of radiation produced by solar flares. Among SMM's primary science objectives was the study of the dynamics of solar flares and the study of solar magnetic fields associated with the flare phenomenon.

The High Altitude Observatory (HAO) provided a white-light coronagraph/polarimeter (C/P) to study the relationship of the corona to the flare process. This instrument obtained coronal images from March through September of 1980 before suffering an electronics failure that rendered it inoperative. A few weeks later, a power failure occurred in the Attitude Control System (ACS) of the SMM spacecraft; consequently, stable pointing of the spacecraft was no longer possible, and the entire spacecraft was put into a dormant ("standby") mode. The SMM spacecraft remained in this state for more than 3 years. The Challenger Space Shuttle ( STS-41C ) was launched on 6 April 1984 to attempt an in-orbit repair of SMM. That mission was successful in replacing both the spacecraft Attitude Control System and the coronagraph's Main Electronics Box.

Atmospheric friction slowly caused the altitude of the SMM spacecraft's orbit to decline. Consequently, the SMM satellite lost attitude control on November 17, 1989, when the spacecraft re-entered the Earth's atmosphere. Re-entry occurred on 2 December 1989 over the Indian Ocean. The coronagraph generated ~240,000 images of the solar corona before its fiery demise.

Additional SMM sites

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SMM Data Use Policy

The use of SMM C/P images for public education efforts and non-commercial purposes is strongly encouraged and requires no expressed authorization. However, it is requested that any such use properly attributes the source of the images as: "Courtesy of HAO/SMM C/P project team & NASA. HAO is a division of the National Center for Atmospheric Research, which is supported by the National Science Foundation."


The Solar Maximum Mission Coronagraph/Polarimenter was designed & operated by the High Altitude Observatory, a division of the National Center for Atmospheric Research, and funded by the National Science Foundation. The SMM Coronagraph/Polarimeter instrument was built by Ball Aerospace Systems Division. The SMM Spacecraft was built by Goddard Space Flight Center, and the SMM project was funded & managed by the National Aeronautics & Space Administration.