NASA is ready to use an Air Force-developed rocket propellant that can allow spacecraft to fly faster, further and carry a heavier payload than current space propellants.
The agency will test out AF-M315, a new class of propellant, in 2015. AF-M315 is about twice as powerful as existing spacecraft propellants and doesn't damage the environment, according to Tom Hawkins, of the Air Force Research Laboratory's Aerospace Systems Directorate. The propellant has been under development for more than 10 years by scientists at the Air Force's Office of Scientific Research and the AFRL.
Hawkins says the propellant might usher in a new era of space travel.
"In terms of performance, it gives [spacecraft] a longer lifetime in orbit, a longer service life; it's something that can give you higher velocity to move from point A to point B," he says. "It's being looked at for interplanetary types of missions and it's got the potential for deeper space types of applications."
That means NASA or a commercial space operator – Hawkins says several are interested – would be able to keep their spacecraft in use for much longer. The propellant would mainly be used once a spacecraft is already in space, but the team is currently looking into terrestrial uses, such as in emergency power generators.
Since the early 1970s, most space missions have been flown with a hydrazine-based propellant. Hydrazine, which is made out of hydrogen and nitrogen, is extremely flammable, dangerous for the environment, and extremely toxic if inhaled, making it tricky to use on manned missions.
Michael Berman, Hawkins' colleague on the project, says missions run with hydrazine were dangerous.
"To handle it, you have to wear personal protective equipment and monitor the hydrogen content of the air," to make sure it didn't ignite," Berman says.
AF-M315, on the other hand, is known as an "energetic ionic liquid" – it's essentially a type of salt in a liquid state. If swallowed, AF-M315 is about as dangerous as coffee and has a "negligible" toxicity if inhaled. It has very little, if any, environmental impact.
Hawkins says its costs will be similar to that of hydrazine-based propellants after the 2015 launch, and the propellant will be ready for widespread use.
"The 2015 launch will put into orbit a spacecraft that will demonstrate the propulsion system for the first time in actual use," Hawkins says. "From then, it'll be on the shelf for other launch opportunities."