National Aeronautics and Space Administration

Wallops Flight Facility


GLAS at Wallops Flight Facility

Welcome to the Geoscience Laser Altimeter System (GLAS) Software Development Team (SDT) Ground Data System Home Page. The SDT supports the GLAS Science Team to develop the GLAS software to produce the Level 1 and Level 2 data products. The GLAS instrument is on the Ice, Cloud, and land Elevation Satellite (ICESat). The GLAS SDT is managed by the NASA Goddard Space Flight Center, Greenbelt, MD, USA.

Icesat Launch : January 13, 2003

icesat_launchIcesat was launch successfully from Vandenberg Air Force Base on January 12,2003 16:45 PST. The launch vehicle was a Boeing Delta II. Separation of the ICESat spacecraft occurred 64 minutes after launch at 5:49 p.m. PST. Initial contact with ICESat was made 75 minutes after launch at 6 p.m. PST as the spacecraft passed over the Svalbard Ground Station in Norway.

ICESat is the latest in a series of Earth Observing System spacecraft, following the Terra satellite launched in December 1999, and the Aqua satellite launched earlier in May of this year. The primary role of ICESat is to quantify ice sheet growth or retreat and to thereby answer questions concerning many related aspects of the Earth climate system, including global climate change and changes in sea level.

End of Mission : August 17, 2010

The Ice, Cloud, and Land Elevation Satellite (ICESat) was successfully decommissioned from operations Saturday August 14, 2010, at approximately 17:37:00 Greenwich Meridian Time (GMT). As part of the final stage of mission decommissioning, the flight operations team passivated the spacecraft in compliance with NASA policy and regulations that seek to “minimize the creation of orbital debris by government and non-government operations in space in order to preserve the space environment for future generations.“ To passivate ICESat, the team sent and activated a series of commands previously stored in the on-board computer to remove all forms of stored energy from the spacecraft. The team verified successful passivation after confirming negative acquisition of signal by ground network tracking stations. Re-entry information will be issued by the NASA Orbital Debris Program Office from data provided by the United States Space Surveillance Network.

ICESat decommissioning and passivation activities started on June 23, 2010, with a series of sixteen controlled burns to lower the orbit and deplete all of the spacecraft’s residual propellant. On July 15, the propellant was fully depleted after the 15th burn. After completion of the orbit -lowering burns, NASA Headquarters approved a special study to collect data from the Global Positioning System (GPS) on board the spacecraft, as it started its natural orbit decay. Since July 15, the ICESat operations team has been retrieving, collecting and processing GPS data. Congratulations to the ICESat team for a successful seven years of operations.