CRISTAL tests its systems on Earth before measuring polar ice
· BehindLines newsroom
Before measuring ice from space, CRISTAL must pass its tests on Earth. In an October 26 progress report, the European Space Agency describes a first solar-panel deployment test following the satellite's assembly at Airbus in Friedrichshafen, Germany.
Power also depends on a mechanism
SpaceTech, the panel manufacturer, announced delivery to Airbus on August 21. The company says the arrays will power the instruments, onboard systems and communications.
Delivering panels and checking their deployment on the satellite are separate steps. The test described by ESA checks mechanisms and software sequences working together. The agency also reports checking the adapter connecting the satellite to its launcher and the separation mechanism.
These operations prepare for flight; they do not yet provide measurements of sea ice.
Two frequencies for the radar instrument
CRISTAL stands for Copernicus Polar Ice and Snow Topography Altimeter, the name of an altimeter intended to measure polar ice and snow topography. The World Meteorological Organization's OSCAR technical record describes its IRIS instrument as a radar altimeter using two bands: Ku, around 13.5 gigahertz, and Ka, around 35.75 gigahertz.
That record also describes interferometry using two antennas. It distinguishes measurements of ice height from estimates of thickness that can be inferred from them. Calling an instrument a radar therefore does not mean that a single observation directly provides every characteristic being sought.
SpaceTech outlines the mission's aims: tracking sea-ice thickness, the snow covering it, and changes in the elevation of ice sheets and glaciers.
The timetable is still about preparation
ESA targets a launch between late 2027 and early 2028. Before that, it plans environmental testing in the Netherlands to check whether the satellite can withstand launch and its future space environment.
This is a scheduling target, with further checks still to come. Successful deployment on the ground marks a technical advance; regular measurement of the polar regions remains the mission ahead.