The Ice, Cloud and land Elevation Satellite-2, or ICESat-2, will measure the height of a changing Earth – one laser pulse at a time, 10,000 laser pulses a second. Launched in 2018, ICESat-2 will carry a laser altimeter that detects individual photons, allowing scientists to measure the elevation of ice sheets, sea ice, forests and more in unprecedented detail.

Our planet's frozen and icy areas, called the cryosphere, are a key focus of NASA's Earth science research. ICESat-2 will help scientists investigate why, and how much, our cryosphere is changing in a warming climate. The satellite will also measure heights across Earth's temperate and tropical regions, and take stock of the vegetation in forests worldwide.