NASA's Mars-Bound Rocket Booster Passes a Key Test

The heavy duty rocket is meant to one day carry humans to Mars.

"Seeing this test today, and experiencing the sound and feel of approximately 3.6 million pounds of thrust, helps us appreciate the progress we’re making to advance human exploration and open new frontiers for science and technology missions in deep space," William Gerstenmaier, associate administrator for the Human Exploration and Operations Mission Directorate at NASA said in a statement.

While the engines used for the Space Launch System will be carrying astronauts on deep space journeys NASA has dreamed about for decades, here's the kicker: The engines are actually leftover from the space shuttle program.

NASA and Aerojet Rocketdyne, the contractor for work on the RS-25, ran several tests on the rocket engines last year, focusing on testing the controller "brain" of the engines and to test out different operating conditions, according to NASA.

Aerojet Rocketdyne and NASA plan to continue working together at the Stennis Space Center to carry out further engine tests, NASA said. The first flight for the Space Launch System is expected to happen no later than November 2018.

Fired up! Miss today's booster test for @NASA_SLS, the world’s most powerful rocket? Watch it now:#JourneyToMars
https://t.co/wRVh32cTVc

— NASA (@NASA) June 28, 2016

Fired up! Miss today's booster test for @NASA_SLS, the world’s most powerful rocket? Watch it now:#JourneyToMars
https://t.co/wRVh32cTVc