SME
Solar Mesosphere Explorer

SME was developed to investigate the processes that create and destroy ozone in the Earth's upper atmosphere. The mission's specific goals were to examine (1) the effects of changes in the solar ultraviolet flux on mesospheric ozone densities, (2) the relationship between solar flux, ozone, and the temperature of the upper stratosphere and mesosphere, (3) the relationship between ozone and water vapor, and (4) the relationship between nitrogen dioxide and ozone. Contact was lost on April 14, 1989 after a battery failure, and the vehicle reentered on March 5, 1991. The mission was managed for NASA by JPL, and was operated by the Laboratory for Atmospheric and Space Physics of the University of Colorado.

Spacecraft
Spin stabilized (~5 rpm). Fixed solar array. Tape recorder. NiCd batteries. The spacecraft was controlled from University of Colorado's Laboratory for Atmospheric and Space Physics (LASP) in Boulder via NASA, GSFC.

Payload
Ultraviolet ozone spectrometer. 1.27 micron spectrometer. Nitrogen dioxide spectrometer. Four-channel infrared radiometer. Solar ultraviolet monitor. Solar proton alarm detector. All instruments were turned off in December, 1988 due to power constraints.

Country of Origin	United States
Customer/User	NASA, NOAA, NCAR, LASP (Univ. of Colo.)
Manufacturer(s)	JPL, Ball Space Systems
Size	1.25 m diameter x 1.7 m high cylinder
Orbit	538 x 542 km, incl. = 97 deg, 3 a.m. - 3 p.m. sun-synchronous
Design Life	1 year

Launch Facts

Name	Int'l Desig.	Date	Site	Vehicle	Orbit	Mass(kg)
Notes
SME	1981-100A	10/6/81	WSMC	Delta 2310	LEO	437
Solar Mesosphere Explorer