If We’re Going to Get to Mars, These Rockets Need to Work


If humans are going to get to Mars, they’re going to need rockets with some serious liftoff power. NASA’s Space Launch System is the most powerful rocket in the world–it has twin five-segment solid rocket boosters, four liquid propellant engines, and a minimum of 70 metric tons of lifting power–but engineers won’t know until June 28th if it’s really going to work.

At 8:05 am MDT on Tuesday, SLS will undergo a qualification ground test at Orbital ATK’s facilities in Utah that will see if its systems are up to snuff. And scientists are setting a high bar. The qualification testing has over 80 objectives–basically, everything but launching skyward–to determine whether SLS is ready to send the Orion spacecraft on the first leg of Exploration Mission-1, an unmanned mission planned for 2018. EM-1 will take Orion 40,000 miles beyond the moon, which is further than any spacecraft built for humans has ever gone. But EM-1, and the manned missions planned for the 2020s, can’t happen unless SLS can get them off the ground.

Granted, everyone’s pretty sure that it will be able to. This test is the fifth of five. And it’s the second of two qualification tests, which are more about how the boosters will perform than if. Tuesday’s burn is mostly a test of the engines to see how much power they provide when the propellant is at a low temperature of about 40 degrees Fahrenheit (so that’s Florida cold, not space cold). The last qualification test back in March tested hot motor performance, with propellant at 90 degrees.