Starship launch 4: What time is the SpaceX flight tomorrow?

SpaceX is preparing Starship, the most powerful rocket ever built, for its next test launch. Here is everything you need to know.

What time is the launch expected to happen?

The launch looks likely to take place in the next week or so, with SpaceX saying it could be as soon as 5 June, pending regulatory approval – each flight must be signed off by the US Federal Aviation Administration.

Other signs point to the same date. Judge Eddie Treviño in Cameron county, Texas, which is home to SpaceX’s Starbase launch site, has issued orders for nearby roads to be closed at the start of June. This precaution is normally taken for launches, but can also be related to some types of ground-based testing.

In official documents, however, Treviño had said specifically that these closures are for “flight testing”, setting out a window of 14 hours on 5 June between midnight and 1400 local time. The documents also give alternative windows of the same duration on 6 and 7 June, should the company need them.

How do I watch the Starship launch?

SpaceX says it will begin a live webcast about half an hour before lift-off.

Where is Starship going?

The fourth flight test will focus on getting Starship back from orbit and carrying out a mock landing of both it and the Super Heavy first-stage booster. A touchdown on land is currently deemed too risky, so both vehicles will make a “soft splashdown” into the ocean. They will use their engines to slow their descent, line up as if they were landing back at base, and gently plop into the water. The first-stage booster is due to land around 7 minutes after lift-off in the Gulf of Mexico, not far from the launch site, while Starship will aim for splashdown in the Indian Ocean around an hour later.

What happened during previous Starship launches?

There have been three Starship launches, all ending in explosions, although that is an expected part of SpaceX’s fail-fast, learn-fast strategy.

The first launch on 20 April last year saw three engines on the first stage – from a total of 33 – fail to ignite. Several more subsequently failed during the flight. The rocket then span out of control, causing a self-destruct safeguard to kick in. The whole flight lasted around 3 minutes and reached a maximum altitude of 39 kilometres.

Starship’s second launch was on 18 November. This time, all 33 engines fired and the rocket flew long enough for the first and second stages to separate. But, as the first stage rotated to begin its slowdown and landing procedure, it exploded. The second stage successfully continued to an altitude of about 149 kilometres, passing the Kármán line that marks the beginning of space. However, a safeguard feature destroyed it when it stopped sending back data, before it had a chance to complete an orbit or make its way back to Earth.

SpaceX’s third Starship test flight on 14 March was at least a partial success as it reached space, carried out fuel transfer tests and travelled further and faster than ever before. But the craft failed to make its scheduled soft landing after losing attitude control mid-flight. Despite this, it achieved a number of key milestones, such the first Starship re-entry from space, the first ever opening and closing of Starship’s payload door in space, and a successful propellant transfer demonstration that will be key to future NASA Artemis missions to the moon.

What happens if this launch goes wrong?

It probably will go wrong, in some respect, as Starship is highly unlikely to complete its mission flawlessly. But any failure will supply data and experience that can be used to improve the design and processes for the fifth launch. SpaceX has shown that it can iterate rapidly and make significant progress with every launch.