Why SpaceX's Starships Keep Blowing up As SN10 Becomes Third to Explode

SpaceX made its first successful Starship landing on Wednesday after a high altitude test, but the rocket ended up exploding into a fireball soon after.

The test, which took place at around 6:15 p.m. EST, was SpaceX's third attempt at launching a Starship rocket to a high altitude before shutting all the engines off, allowing it to plummet towards the Earth, and then restarting all the engines for a vertical landing.

The rocket, called SN10, appeared to successfully touch down 6 minutes and 20 seconds after taking off. It reached an altitude of about 6.2 miles.

The Starship model then stood still on the landing pad for just over eight minutes, before exploding.

SpaceX has not publicly confirmed why the rocket exploded. Kenneth Chang, a science reporter for the New York Times, claimed a leak in SN10's propellant tank may have caused the blast. Other reports specified a possible methane leak. Newsweek has contacted SpaceX for comment.

Despite the fireball, SpaceX hailed the mission as a success. The company said: "As if the flight test was not exciting enough, SN10 experienced a rapid unscheduled disassembly shortly after landing. All in all a great day for the Starship teams."

SpaceX CEO Elon Musk tweeted afterwards: "RIP SN10, honorable discharge."

RIP SN10, honorable discharge

— Elon Musk (@elonmusk) March 4, 2021

The SN10 test marked the third time in a row that a test of a Starship rocket ended in an explosion. The previous two prototypes, SN9 and SN8, both blew up after coming down too hard and failing to land correctly.

SN8 launched on December 9 2020. Again, the test took the rocket to a high altitude, that time of around 7.8 miles. As in the SN10 mission, the rocket flipped onto its side before plummeting to Earth and attempting to right itself with its engines for a slow and steady landing.

SN8 hit the landing pad vertically, but came in too fast and exploded on touchdown. Musk tweeted afterwards: "Fuel header tank pressure was low during landing burn, causing touchdown velocity to be high & RUD, but we got all the data we needed!" In this case "RUD" stands for "rapid unscheduled disassembly," another way of saying the rocket blew up.

Then there was SN9, which lifted off on February 2 2021. It reached an altitude of 6.2 miles, performed the flip maneuver, and attempted to land.

But the rocket came in both too fast and at an angle, causing another explosion. BBC science correspondent Jonathan Amos said at the time it appeared as though only one of its three engines had ignited properly for landing.

On that occasion neither SpaceX nor Musk revealed what exactly had caused the landing failure.

Once it gets past this explosive development stage, SpaceX plans to use the Starship rockets for future manned missions to the Moon and Mars.

People look at Starship rocket
People look at an early prototype of Starship at SpaceX's Texas launch facility on September 28, 2019 in Boca Chica near Brownsville, Texas. SpaceX made its first successful Starship landing on Wednesday. Loren Elliott/Getty