For a couple of weeks, SpaceX engineers and technicians have been conducting a series of tests on its Starship prototype vehicle in South Texas. For example, they have loaded liquid oxygen and liquid methane fuels onto the vehicle, studied the cryogenic properties of the fuel tanks, and then removed the propellant.

As expected, this was all a little dull for those eager to see Starhopper light its single Raptor engine—until Wednesday evening. Shortly after night fell over the southern Texas test facility, Starhopper roared to life for the first time, firing its Raptor engine and lifting briefly off the pad. The vehicle did not go far, because for now it remains solidly tethered to the ground.

This test firing was apparently successful. "Starhopper completed tethered hop. All systems green," SpaceX founder Elon Musk tweeted shortly after the test.

This represents the first phase of tests for the Starship vehicle. The prototype built in South Texas, near Brownsville, is not a particularly high-fidelity mock-up, but it is needed to test how a vehicle designed to land propulsively on other worlds, and take off, handles such conditions. These minute hops will progressively become larger as SpaceX adds two more Raptor engines to Starhopper in the coming months.

It is not known how high Starhopper will eventually climb during these tests. Back in 2012 and 2013, when SpaceX was testing its Grasshopper vehicle to prove out technologies for landing its Falcon 9 rocket, the vehicle climbed as high as 744 meters during its flight campaign.

The work on Starhopper continues as SpaceX prepares to test-fire another rocket—the Falcon Heavy booster. The window for a static fire test opens at 6pm ET Thursday, and closes at midnight. Provided this test firing of all of the vehicle's 27 engines is successful, the Arabsat-6A launch may occur as early as Sunday, April 7, at 6:36pm ET. This will be only the Falcon Heavy rocket's second flight.

Listing image by SpaceX