ESA's Cryosat-2 ice mission is set for launch today, aiming to give scientists some hard evidence on the state of the world's ice caps.
By measuring the tiny variations in the thickness of ice floating in the polar oceans and changes in the vast ice sheets on land, it's hoped the satellite will lead to a better understanding of the role ice plays in the Earth system and climate change.
"After the loss of the original CryoSat in 2005, we are extremely happy to have reached this point after four years rebuilding the satellite, including a number of improvements on the original," said Richard Francis, ESA's Project Manager.
"We are now very much looking forward to a successful launch and then delivering the data the scientific community so badly needs to build a true picture of what is happening in the fragile polar regions."
The go-ahead to launch follows a nine-hour dress rehearsal yesterday.
CryoSat-2 will be launched on a Dnepr rocket - actually, a converted intercontinental ballistic missile - from an underground silo at the Baikonur Cosmodrome in Kazakhstan at 15:57 CEST. It will orbit at a height of 717km.
Data is expected to start coming in later this year after the initial checkout and commissioning phase ends.
"All systems and facilities that will support the mission in flight are fully ready. We are looking forward to an intensive early operations period lasting through Sunday, with 24-hour shift coverage from the teams at ESOC. The ground segment has been verified and we are are ready to go," said Flight Operations Director Pier Paolo Emanuelli.
The launch can be watched live via ESA's CryoSat website.