ICESat-2

The Ice, Cloud and Land Elevation Satellite 2 (ICESat-2), being developed by the Nasa Goddard Space Flight Center (GSFC), aims to gather altimetry data of the Earth’s surface to evaluate polar ice changes and global vegetation biomass.

It is expected that ICESat-2 will be launched from Space Launch Complex-2 at Vandenberg Air Force Base, California, US, in September 2018. It will be placed in a near-circular Earth polar orbit at a 92° orbital position.

The mission is Nasa’s follow-up to the ICESat satellite, which was operational between 2003 and 2009.

Design and development

“ICESat-2 satellite will characterise the polar-sea ice and global vegetation heights, and measure changes in the elevation of polar ice sheets to understand the changes.”

Orbital Science Corporation (now called Orbital ATK) was awarded a $135m contract for the design and construction of ICESat-2 in August 2011. Construction, assembly and testing are being carried out at Orbital’s satellite manufacturing facility in Gilbert, Arizona, US.

The satellite will be based on the LEOStar-3 platform developed by Orbital ATK. It will have a launch mass of 1,387kg (3,057.8lb) and solar arrays with three-axis stabilisation and zero-momentum bias. It will have a design lifespan of three years, although this can be extended up to seven years.

Mission details



Delta IV is an advanced orbital launch vehicle designed and developed by United Launch Alliance.


ICESat-2 satellite will characterise the polar-sea ice and global vegetation heights, and measure changes in the elevation of polar ice sheets to understand the changes, as well as their contribution to current and future sea-level rises.

It will also help scientists from Nasa’s Earth science programme to develop a better scientific understanding of the Earth’s system.

ICESat 2 instruments

The LEOStar-3 platform supports payloads of up to 4,000kg. The satellite will be fitted with an Advanced Topographic Laser Altimeter System (ATLAS) instrument with a 532nm wavelength multiple-beam laser. The laser is currently being tested at the Goddard Space Flight Center in Greenbelt, Maryland, US, and will return to the Orbital ATK in 2018, where it is due to undergo additional testing.

The laser will allow scientists to calculate Earth’s elevation in inclined areas, by measuring the distance through the detection of just a few photons from each visible, green laser pulse and the timing of their round-trip flight between satellite and earth.

Launch vehicle

“The mission is Nasa’s follow-up to the ICESat satellite, which was operational between 2003 and 2009.”

United Launch Services signed a contract to provide Delta II rocket launch services in February 2013. Delta II is a two-stage rocket that can be configured with an optional spin-stabilised, third-stage motor.

The first stage of the rocket is powered by the RS-27A main engine and solid rocket graphite-epoxy motors, while the second includes an Aerojet AJ10-118K engine and redundant attitude control system. The optional third stage is powered by a Star-48B solid rocket motor.

Contractors

Fibertek and Sigma Space were awarded with a $35m contract to design, test, fabricate, deliver, operate and evaluate space laser systems for the ICESat-2 ATLAS instrument in July 2009.

RUAG Space was contracted to supply two space-hardened GPS receivers for the satellite mission in August 2012.

In September 2012, Emcore Corporation received a contract to provide solar panels and advanced ZTJ triple-junction solar cells.

EaglePicher Technologies was awarded a contract in July 2013 to provide lithium ion batteries.

 

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