NASA is all set with its next mission to understand the cause of melting ice sheets. NASA will be launching a laser-armed satellite in September, that will measure the heights of Earth’s polar ice with unparalleled details. In recent years, the global sea level of Greenland and Antarctica alone has been raised by more than a millimetre a year, owing to the melting of ice sheets. This means that approximately one-third of the sea level has risen so far, and the rate is escalating.
NASA said in a statement on Thursday that the mission is scheduled to be launched from Vandenberg Air Force Base in California on September 15. The mission will be known as the Ice, Cloud and Land Elevation Satellite-2 (ICSESat-2). The average annual elevation change of land ice covering Greenland and Antarctica to within the width of a pencil will be measured by the satellite. ICESat-2 will capture 60,000 such measurements every second. As stated in The Hans India, Michael Freilich, Director of the Earth Science Division of the Earth Science Division in NASA’s Science Mission Directorate said, "The new observational technologies of ICESat-2 will advance our knowledge of how the ice sheets of Greenland and Antarctica contribute to sea level rise."
ICESat-2 asserts that this will revolutionise NASA’s 15-year record of monitoring the change in polar ice heights. The monitoring began with the first ICESat mission in 2003 and NASA’s Operation IceBridge continued it in 2009. IceBridge was a flying research campaign that kept track of the increasing rate of change. ICESat-2 will measure height by timing the duration it takes for individual light photons to travel from the spacecraft to Earth and back with the help of its Advanced Topographic Laser Altimeter System (ATLAS).
"ATLAS required us to develop new technologies to get the measurements needed by scientists to advance the research," said Doug McLennan, ICESat-2 Project Manager. "That meant we had to engineer a satellite instrument that not only will collect incredibly precise data, but also will collect more than 250 times as many height measurements as its predecessor," he added.
ATLAS will fire 10,000 times each second and by doing so it will send hundreds of trillions of photons to the ground in six beams of green light. With the help of so many photons returning from multiple beams, ICESat-2 will be able to receive a better and classified view of the ice surface as compared to its predecessor.
As it circles Earth from pole to pole, ICESat-2 will measure ice heights along the same path in the polar regions four times a year, providing seasonal and annual monitoring of ice elevation changes. Apart from poles, the measurement of the height of ocean and land surfaces, including forests, will be done by ICESat-2