An Australian rocket scientist has built a prototype ion drive that could one day power a return trip to Mars using recycled space junk for fuel. 

Recent PhD graduate Paddy Neumann made headlines last year when his ion drive obliterated NASA's fuel efficiency record, and just last week, he signed a deal with Europe's biggest aerospace company, Airbus Defence & Space, to launch it to the International Space Station for testing.

The partnership was announced last Thursday at the International Astronautical Congress in Mexico, and marks the first time that Airbus has taken on a customer for the external research platform it plans to install on the International Space Station (ISS) by the end of 2018.

"We've been testing on Earth in a vacuum system to simulate space, but it's a small vacuum system, so this will be the first real test of a true space environment with on-board monitoring of the system," Neumann's co-inventor at the University of Sydney, Marcela Bilek, told ABC News.