A Prototype Starship Hops a Little Closer to the Moon

Tuesday’s test in south Texas capped a very good week for SpaceX.

starship hop.jpg
The SN5 prototype goes airborne over Boca Chica, August 4, 2020.

Elon Musk created SpaceX almost two decades ago with one ambitious goal in mind: to make humanity a multi-planet species. On Tuesday night, he took one sideways leap toward making it happen.

It’s been a great summer for SpaceX. Two months ago, the company launched a pair of NASA astronauts, Doug Hurley and Bob Behnken, into space, and last weekend the same Dragon vehicle in which they arrived returned them safely to Earth. The mission was a major milestone, the first time any privately owned spacecraft has delivered astronauts to orbit. But Musk sees it as a steppingstone to something even bigger.

“This day heralds a new age of space exploration,” he said after watching Hurley and Behnken arrive in Houston following their landing. “We are going to the moon, we’re going to have a base on the moon, and we’re going to send people to Mars and make life multiplanetary,” he exulted.

To that end, Musk has challenged engineers at SpaceX to build a massive, deep-space rocket out of rolls of stainless steel. On Tuesday evening, the fruits of their labor took flight from the company’s Boca Chica launch site on the U.S./Mexico border.

Just before the sun went down in south Texas, a single Raptor engine roared to life, propelling a large-scale prototype of SpaceX’s interplanetary spaceship, called Starship, into the air. The test vehicle, designated SN5, looked like a giant, silver spray can as it climbed 150 meters (500 ft) above the ground, sliding sideways as it flew. Then, right on cue, a set of stubby-looking landing legs deployed, allowing the craft to touch back down on terra firma less than a minute later.

At first spectators couldn’t tell if the prototype survived its hop. But once the dust cleared, the silvery tube was standing in triumph.

Starship SN5 150m Hop

“Mars is looking real,” Musk tweeted shortly after the hop.

Just shy of a year ago, he had stood in front of his vision: a gleaming, full-scale mockup of the Starship, which looks like something from a 1950s science fiction movie. “It’s going to be pretty epic to see that thing take off and come back,” he told a rapt audience, teasing out a few engineering details along with his grand plan for humanity.

At the time, Musk predicted that a full-scale version would fly within months. Since then the company has lost four prototypes to over-pressurization events; they either exploded, imploded or caught fire before they could begin to fly.

Those losses were not in vain, according to SpaceX, which learned from the tests how to build a better model.

“SpaceX learns more from its failures than it does its successes,” company President and COO Gwynne Shotwell said during a news conference ahead of the May 30 astronaut crew launch. The company has continuously tweaked the design, including experimenting with different steel alloys to ensure the vehicle could withstand the amount of thrust the Raptor engine puts out and still remain structurally sound.

All that tweaking led to the 30-meter-tall prototype used in Tuesday’s test. It’s a bit smaller than the actual rocket will be, but is the largest mockup to leave the ground so far. (Last summer, a shorter, stubbier version, resembling a water tower, was the first to hop.)

When it does fly, the completed Starship will stand 50 meters high and be launched into orbit atop a Super Heavy rocket booster, which currently exists only on paper. The operational Starship will sport additional structural elements the SN5 lacks, including a large nose cone, flaps, and an interstage.

Tuesday’s prototype featured the Starship’s most crucial element—its engine. The test had a couple of key objectives: to test that the stainless-steel structure could withstand launch and landing, and to demonstrate that SpaceX had a handle on its new Raptor engine. While the SN5 has only one of these, the final Starship vehicle will need six Raptors to carry up to 100 people, says Musk.

Starship’s ultimate purpose is to land on other worlds, including the moon. NASA has picked SpaceX as one of the contenders to deliver astronauts to the lunar surface as early as 2024.

Will this same prototype SN5 fly again? SpaceX is as stingy as ever with information, but Musk Tweeted after Tuesday’s test that several short hops are needed to smooth out the launch process, and that higher-altitude flights, with flaps added, will follow after that. The company continues to work on other prototypes inside the tents and high-bay facilities at Boca Chica.

Before a Starship can attempt orbital flight, SpaceX needs to build the “Super Heavy” that will act as the craft’s first-stage booster. Mars is still many steps away. But Tuesday’s hop makes it seem just a bit closer.

Get the latest stories in your inbox every weekday.