Icicles! On an engine that burns at 5000 degress!

A technology development engine that may help NASA safely return astronauts to the lunar surface has successfully completed its third round of testing. The goal of these tests is to reduce risk and advance technology for a reliable and robust rocket engine that could enable America’s next moon landing.

The tests by Pratt & Whitney Rocketdyne in West Palm Beach, Fla., helped to gather data on this concept engine that might play a role in the next stage of human exploration of the moon. Most rockets make spacecraft travel faster. The goal of a lunar lander descent engine is to slow the vehicle so astronauts can land safely.