SpaceX’s Red Dragon mission to Mars could mark a lot of firsts when it comes to space exploration, but one of the coolest new things about the whole project is a fancy, incredibly cool-sounding way to land on the planet’s surface: Supersonic retropropulsion.
“This has never been done before,” said Phil McAlister, NASA’s director of commercial spaceflight development in a Wednesday teleconference about the agency’s collaboration with SpaceX. “Putting a large mass into the mars atmosphere using supersonic retropropulsion.”
Typically, when a spacecraft approaches a planet, it’s going incredibly fast, and it needs to have the ability to slow down before touching down, otherwise — kablooey! — it’ll crash into the surface in an and be nothing more than a smoldering mass of wreckage. NASA’s Curiosity mission to Mars slowed down for an easier landing by firing its rockets towards the surface. This technique is called subsonic retropropulsion.
Supersonic retropropulsion, as you may have guessed, is similar except for one crucial difference: The spacecraft will fire its rockets while moving faster than the speed of sound. This allows the craft to ditch the parachute that its subsonic brethren use to slow down, making for a lighter and faster trip.
To read more, click here.