On Tuesday night, in South Texas, SpaceX launched its Starhopper test car for the second time. During this test it flew much higher than last month, almost straight up to 150 meters. Under the power of a single Raptor engine, the vehicle moved smoothly sideways for about 100 meters before a controlled descent and descent in the middle of a landing pad.
From a technical point of view, the test was impressive, demonstrating the thrust and vector control of the new Raptor engine. This was the first time a large rocket engine that fired liquid methane propellant made a significant flight, and it seemed to be most, if not quite, successful. SpaceX engineers can take confidence from this test as they complete the construction of Starship orbital prototypes in Texas and Florida later this year.
However, the test may have had more political significance. SpaceX seeks to demonstrate that Starship is a viable vehicle for NASA to consider flying astronauts to and from the Moon and other destinations. Visually arresting the escape of the stubby Starhopper: it took off in a cloud of smoke and landed in the reddish – almost marsh red – dust it kicked up at the landing site.
Some politicians may begin to notice. Earlier this month, a spokesman for Ted Cruz, a Republican senator from Texas, told Ars, "With respect to SpaceX's Starship, the senator and his staff have been watching closely and are excited about the vehicle's outlook and the economic activity and innovation that is happening as a result of Texas. "
The timing may have been accidental – but about an hour after SpaceX tested the Starhopper vehicle, NASA's Marshall Space Flight Center tweeted three photos of a copy of its Space Launch System rocket loaded into a test stand at Mississippi's Stennis Space Center.
"Technicians lift and install a copy of @NASA_SLS core steps in preparation for the SLS Green Run test," Alabama-based NASA Center tweeted. Marshall manages the development of the SLS rocket.
NASA has spent around $ 230 million refurbishing and modifying the B-2 test stand for this Green Run test firing of the SLS rocket. The rocket itself has been under development since 2011, at a cost of around $ 14 billion and counting. The first test firing of the rocket can happen next year at Stennis.
However, the SpaceX Starship program has progressed rapidly. Construction of the Starhopper test vehicle – the affectionately nicknamed "Flying Water Tower" because of its appearance – began only in mid-December 2018. The engine tests began a few months later, with the first 20m flight test in July, followed by Tuesday night's 150 meter hop.
SpaceX has now learned what it could from Starhopper, and it will continue with full-size suborbital prototypes for Starship that can do test flights later this year. The Starship vehicle, which will be shot from Earth as the second phase of the Super Heavy missile development, may take some time in 2020 or later, depending on prototype testing.
A step towards Mars
It's easy to dismiss Starhopper for its slamming construction or the fact that it only flew 150 meters. After all, what does such a test achieve?
Perhaps an analogy can be found in SpaceX's Grasshopper test program. For the lawn mower test, a Falcon 9 first stage fuel tank used for qualification testing was modified with landing legs. From September 2012 through October 2013, the company flew the vehicle several times to an altitude of up to 744 feet above the site in McGregor, Tex. This may have seemed similarly flashy and shambolic – just less than three years later, the company had landed Falcon 9 rockets launching the first stage on land and sea after trips to space.
From this point of view, Starhopper's two flights were to be seen as steps towards a vehicle of potentially revolutionary capabilities, including landing and taking propulsion from distant worlds including the Moon and Mars. SpaceX might not get there. This project may be too difficult or may require too much funding. But betting on a company that works just as hard, fast and with as much urgency as this is unwise.
Listing image by Trevor Mahlmann for Ars