The first Ice, Cloud, and land Elevation Satellite (ICESat)

The first Ice, Cloud, and land Elevation Satellite (ICESat) mission, part of NASA's Earth Observing System (EOS), was launched on January 12, 2003 from Vandenberg Air Force Base in California in a near-polar orbit. The Geoscience Laser Altimeter System (GLAS) on ICESat measured ice sheet elevations and changes in elevation through time, height profiles of clouds and aerosols, land and water elevations, vegetation cover, and also enabled estimates of sea ice thickness in Earth’s polar regions until late 2009.

Utilizing detailed engineering diagrams of the Delta II rocket including its second stage, this animation shows the launch of ICESat and a secondary payload, the Cosmic Hot Interstellar Plasma Spectrometer Satellite (CHIPSat) in the module below it. After separating from the top of the second stage, ICESat’s operational phase began with the deployment of its solar arrays. The three lasers within GLAS then emitted both infrared and green laser pulses using its 1064 nm detectors for altimetry and its 532 nm detectors for assessing the atmosphere. The lasers and the ancillary equipment needed during instrument operations are shown in cutaway views in the first animation. After ICESat’s three lasers were consumed on orbit, the satellite was deorbited into the Arctic Ocean on August 30, 2010.

Future ICESat missions will extend and improve assessments from the first mission, as well as monitor ongoing changes around the globe. ICESat-2 is scheduled to launch in September 2018, again from Vandenburg. Together with other elements of NASA Earth science research as well as current and planned EOS satellites, ICESat data will enable scientists to study the Earth's climate system and especially help predict how ice sheets and sea level will respond to future climate change.