Encyclopedia Astronautica

American solar satellite. One launch, 1980.02.14. The Solar Maximum Mission (SMM) was intended primarily to study solar flares and related phenomena.

Launched during a period of maximum solar activity, SMM observed more than 12,000 flares and over 1,200 coronal mass ejections during its 10 year lifetime.

SMM provided measurements of total solar radiative output, transition region magnetic field strengths, storage and release of flare energy, particle accelerations, the formation of hot plasma, and coronal mass ejection. The payload also observed the short-wavelength and coronal manifestations of flares.

Observations from SMM were coordinated with in situ measurements of flare particle emissions made by the ISEE 3 satellite. SMM was the first satellite to be retrieved, repaired and redeployed in orbit. In 1984, the STS-41C Shuttle crew restored the spacecraft's malfunctioning attitude control system and replaced a failed electronics box for the coronagraph/polarimeter. SMM collected data until 24 November 1989, and re-entered on 2 December 1989.

The solar payload instruments and the sun-sensor system were contained in the instrument module occupying the top 2.3 meters of the craft. The Multimission Modular Spacecraft (MMS), below the instrument module, contained the systems for attitude control, power, communication, and data handling. Two fixed solar panels, located between the instrument module and the MMS supplied 1500-3000 W. The fine-pointing Sun-sensor system had a precision of 1 arcsec along all 3 axes. The payload included:

  • Active Cavity Radiometer Irradiance Monitor (ACRIM) - measured total solar irradiance.
  • Gamma Ray Spectrometer (GRS) - studied the composition of solar and interstellar gamma ray emissions.
  • Hard X-ray Burst Spectrometer (HXRBS) - studied hard X-ray spectra of solar flares in 15 energy channels between 20-260 keV.
  • soft X-ray Polychromator (XRP) - monitored soft X-ray emissions.
  • Hard X-ray Imaging Spectrometer (HXIS)
  • Ultraviolet Spectrometer and Polarimeter (UVSP) - a raster imager providing 0.04 A sp. res.
  • Coronograph/Polarimeter - studied the faint solar corona between 2 and 5 solar radii with a 6.4 arcsec resolution.

AKA: Solar Maximum Mission.
Gross mass: 2,315 kg (5,103 lb).
Height: 4.00 m (13.10 ft).
First Launch: 1980.02.14.
Number: 1 .

More... - Chronology...

Associated Countries
See also
  • Delta The Delta launch vehicle was America's longest-lived, most reliable, and lowest-cost space launch vehicle. Development began in 1955 and it continued in service in the 21st Century despite numerous candidate replacements. More...

Associated Launch Vehicles
  • Delta American orbital launch vehicle. The Delta launch vehicle was America's longest-lived, most reliable, and lowest-cost space launch vehicle. Delta began as Thor, a crash December 1955 program to produce an intermediate range ballistic missile using existing components, which flew thirteen months after go-ahead. Fifteen months after that, a space launch version flew, using an existing upper stage. The addition of solid rocket boosters allowed the Thor core and Able/Delta upper stages to be stretched. Costs were kept down by using first and second-stage rocket engines surplus to the Apollo program in the 1970's. Continuous introduction of new 'existing' technology over the years resulted in an incredible evolution - the payload into a geosynchronous transfer orbit increasing from 68 kg in 1962 to 3810 kg by 2002. Delta survived innumerable attempts to kill the program and replace it with 'more rationale' alternatives. By 2008 nearly 1,000 boosters had flown over a fifty-year career, and cancellation was again announced. More...
  • Delta 3910 American orbital launch vehicle. Three stage vehicle consisting of 9 x Castor 4 + 1 x ELT Thor/RS-27 + 1 x Delta P /TR-201 More...
  • Delta 3000 American orbital launch vehicle. The Delta 3000 series upgraded the boosters to Castor 4 solid propellant strap-ons, while retaining the Extended Long Tank core with RS-27 engine. The 3910 series used the TRW Lunar Module engine in the second stage, while the 3920 series reintroduced the Aerojet AJ110 Delta engine. More...

Associated Manufacturers and Agencies
  • NASA American agency overseeing development of rockets and spacecraft. National Aeronautics and Space Administration, USA, USA. More...
  • Fairchild American manufacturer of rockets, spacecraft, and rocket engines. Fairchild, USA. More...

  • McDowell, Jonathan, Jonathan's Space Home Page (launch records), Harvard University, 1997-present. Web Address when accessed: here.
  • JPL Mission and Spacecraft Library, Jet Propulsion Laboratory, 1997. Web Address when accessed: here.
  • McDowell, Jonathan, Launch Log, October 1998. Web Address when accessed: here.

Associated Launch Sites
  • Cape Canaveral America's largest launch center, used for all manned launches. Today only six of the 40 launch complexes built here remain in use. Located at or near Cape Canaveral are the Kennedy Space Center on Merritt Island, used by NASA for Saturn V and Space Shuttle launches; Patrick AFB on Cape Canaveral itself, operated the US Department of Defense and handling most other launches; the commercial Spaceport Florida; the air-launched launch vehicle and missile Drop Zone off Mayport, Florida, located at 29.00 N 79.00 W, and an offshore submarine-launched ballistic missile launch area. All of these take advantage of the extensive down-range tracking facilities that once extended from the Cape, through the Caribbean, South Atlantic, and to South Africa and the Indian Ocean. More...
  • Cape Canaveral LC17A Delta launch complex. Part of a dual launch pad complex built for the Thor ballistic missile program in 1956. Pad 17A supported Thor, Delta, and Delta II launches into the 21st Century. More...

SMM Chronology

1980 February 14 - . 15:57 GMT - . Launch Site: Cape Canaveral. Launch Complex: Cape Canaveral LC17A. LV Family: Delta. Launch Vehicle: Delta 3910. LV Configuration: Delta 3910 635/D151.
  • SMM - . Payload: Solar Maximum Mission. Mass: 2,315 kg (5,103 lb). Nation: USA. Agency: NASA Greenbelt. Class: Astronomy. Type: Solar astronomy satellite. Spacecraft: SMM. Decay Date: 1989-12-02 . USAF Sat Cat: 11703 . COSPAR: 1980-014A. Apogee: 408 km (253 mi). Perigee: 405 km (251 mi). Inclination: 28.5000 deg. Period: 92.70 min. Summary: Solar Maximum Mission; solar observatory; repaired 4/9/84 by STS-41C in orbit. Spacecraft engaged in practical applications and uses of space technology such as weather or communication (US Cat C). .

1989 November 23 - .
  • Solar Maximum ends operating life. - . Nation: USA. Spacecraft: SMM. Summary: SMM finished collected data . It re-entered on December 2, 1989..

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