|Mission type||Solar astronomy|
|Operator||NASA / JPL|
|Mission duration||7 years|
|Launch mass||288 kilograms (635 lb)|
|Start of mission|
|Launch date||20 December 1999, 07:13UTC|
|Launch site||Vandenberg LC-576E|
|Semi-major axis||7,067.28 km (4,391.40 mi)|
|Perigee||675 km (419 mi)|
|Apogee||717 km (446 mi)|
|Epoch||5 December 2013, 12:18:57 UTC|
The Active Cavity Radiometer Irradiance Monitor Satellite, or ACRIMSAT is a dedicated satellite and instrument that is one of the 21 primary observational components of NASA's Earth Observing System program. ACRIMSAT was launched on 20 December 1999 from Vandenberg Air Force Base as the secondary payload on a Taurus rocket along with KOMPSAT. It was placed into a high inclination, 700 km. sun-synchronous orbit from which the ACRIM3 instrument monitors total solar irradiance (TSI).
ACRIM3 has made measurements of the TSI since the start of its mission in April 2000. It extends the TSI measurement database begun by earlier ACRIM instruments on the NASA Solar Maximum Mission (ACRIM1: 1980-1989) and Upper Atmosphere Research Satellite (ACRIM2: 1991-2001).
ACRIMSAT/ACRIM3 tracked TSI during a 2004 transit of Venus and measured the 0.1% reduction in the solar intensity caused by the planet's shadow. It also recorded data for the 2012 Transit of Venus.
Richard C. Willson is the principal investigator and leads the science team. Willson designed the active cavity radiometer type of sensor used by self-calibrating satellite TSI monitoring experiments. The ACRIM3 instrument was a collaboration between Willson, original JPL/ACRIMSAT Project Manager Ronald Zenone and ACRIM3 Instrument Scientist Roger Helizon. The Mission is controlled using the ACRIMSAT tracking station at the Jet Propulsion Labs (JPL) Table Mountain Observatory in Southern California. Co-Investigators are: Nicola Scafetta (climate impact of solar variability), Hugh Hudson (solar physics)and Alexander Mordvinov (solar physics).
ACRIMSAT (international designator 1999-070B) is a spin-stabilized, single-purpose satellite constructed by Orbital Sciences Corporation. Its total cost, including the instrument, launch, ground station, operations and science team activities during its 13 1/2 year mission to date has been less than $50 million.
- "ACRIMSAT Satellite details 1999-070B NORAD 26033". N2YO. 5 December 2013. Retrieved 6 December 2013.
- Composite TSI Time Series
- Schneider, J. M.; Pasachoff; Willson, Richard C. (2006). "The Effect of the Transit of Venus on ACRIM's Total Solar Irradiance Measurements: Implications for Transit Studies of Extrasolar Planets". The Astrophysical Journal (641): 565–571. doi:10.1086/500427.
- "Catalog Page for PIA15820". nasa.gov.
- "ACRIM Staff Information". acrim.com. Retrieved 2015-07-25.
- AcrimSat Launch
- ACRIM Science Team homepage
- ACRIMSAT Project homepage
- Fact sheet on the mission
- ACRIMSAT: NASA Science Missions