NASA’s Europa Clipper will start its journey to Jupiter’s icy moon aboard a Falcon Heavy rocket built by SpaceX. NASA will pay SpaceX $178 million to launch the vehicle in October 2024.

The Europa Clipper got the green light from NASA in 2015. It will fly by the moon 45 times, providing researchers with a tantalizing look at the icy world, believed to have an ocean lurking under its icy crust. The Clipper is equipped with instruments that will help scientists figure out if the moon could support life.

For years, the Clipper was legally obligated to launch on NASA’s long-delayed Space Launch System (SLS). But with the SLS perpetually delayed and over budget, NASA has urged Congress to consider allowing the Europa Clipper to fly commercial. Switching to another vehicle could save up to $1 billion, NASA’s inspector general said in 2019.

NASA got permission to consider commercial alternatives to the SLS in the 2021 budget, and started officially looking for a commercial alternative soon after.

The SLS has powerful allies in Congress, who have kept the costly program alive for years, even as it blew past budgets and deadlines. The first flight of the SLS was originally supposed to happen in 2017. That mission — launching an uncrewed trip around the Moon — has since been pushed to November 2021, and keeping to that new schedule remains “highly unlikely” according to NASA’s Office of Inspector General, a watchdog agency.

SpaceX first launched its Falcon Heavy rocket in 2018, and started flying satellites in 2019. Earlier this year, NASA selected the rocket as the ride to space for two parts of a planned space station orbiting the Moon.