Emily Atkinson
Live reporter

Image source, SpaceX

Today was nothing short of extraordinary.

As per the plan, the Starship rocket has successfully returned to Earth on its fourth test flight, landing in the Indian Ocean.

It's a major step forwards for SpaceX, following three previous failed attempts. (But this is all part of the trial-and-error of the programme, the company says).

Now, the wait begins for whatever comes next.

This page was edited by me, with contributions from our science correspondent Jonathan Amos and science editor Rebecca Morelle. Thanks for joining us.

Watch the moment Starship landed in the Indian Ocean, leading to wild celebrations in the SpaceX ground control centre.

(Be aware, the rocket's external camera seemed to crack on its return to Earth.)

• 150 metric tonnes: The amount of payload Starship could put in Low-Earth Orbit (LEO), a few hundred kilometres up
• $2bn (£1.56bn): How much Elon Musk said he planned to spend in the year 2023 to develop Starship vehicles in Texas
• 74 meganewtons (16.6 million lbs): Starship's maximum thrust - the force produced by 33 engines at the rocket's base
• 4,600 tonnes (10 million lb): The mass of liquid methane and liquid oxygen that is pumped into the rocket on the pad
• 100 people: The number of passengers SpaceX says could one day be carried on a single Starship launch

It's not every day you get to watch a rocket launch - let alone a successful one.

On the periphery of Space X's Boca Chica launchpad, in Texas, crowds gathered - seriously impressive kit in tow - as they waited for Starship to blast off into the sky.

Here are a few snaps from the ground:

Image source, Reuters

Image source, Reuters

Jonathan Amos
Science correspondent

Image source, Getty Images

Among these test flights’ keenest observers is the US space agency, Nasa.

Starship is critical to Nasa's Artemis programme to put astronauts back on the Moon this decade.

A version of Starship would act as the landing craft, taking the crew from lunar orbit down to the surface - and then lifting them back off again.

SpaceX will first have to show it can produce a safe and reliable vehicle, before astronauts are permitted to climb aboard.

Nasa has scheduled late 2026 for when it would like to see boots back on the moon.

Will SpaceX be ready by then? The timeline is challenging, for sure.

• As a reminder, you can watch repeats of the flight, landing, and celebrations by pressing play at the top of the page

Now SpaceX founder Elon Musk says: "Despite loss of many tiles and a damaged flap, Starship made it all the way to a soft landing in the ocean!"

Image source, Reuters

SpaceX has just posted, external on (where else) X: "Splashdown confirmed! Congratulations to the entire SpaceX team on an exciting fourth flight test of Starship!"

Jonathan Amos
Science correspondent

We’re done. The Ship is down.

We could see on the imagery that parts of the Ship were coming apart in the extreme forces imposed on it during re-entry.

But even after the lens on a camera cracked, it was evident the vehicle was able to descend broadly intact all the way to the sea surface.

Telemetry was still being sent back right at the very end. Was it able to fully perform its flip manoeuvre and hover, it’s difficult to say. It may have been quite ungainly.

But all told, this was a very, very impressive outing for Starship.

It got much further through its flight profile than on the first three test missions.

SpaceX and boss Elon Musk will be thrilled with how things have gone.

• Watch recaps and repeats of the descent by pressing play above

The Starship rocket has seemingly successfully splashed down in the Indian Ocean.

We'll bring you more on this remarkable news shortly.

Image source, SpaceX

Jonathan Amos
Science correspondent

We’ve gone through peak heating - and the Ship still looks stable.

This is really encouraging.

The Ship is going to have a go at doing a controlled hover above the Indian Ocean waters – just as the booster did over the Gulf’s waters.

The Ship is coming in with a broadly horizontal orientation, which means it will have to perform flip to do the hover.

Jonathan Amos
Science correspondent

Fabulous imagery as the the Ship plunges to Earth.

A plasma – a super-heated, ionised gas – is building up around the vehicle.

The Ship still looks stable.

Remember: you can watch this all happening live by clicking the Play button at the top of this page.

Jonathan Amos
Science correspondent

The Ship is preparing to come back into the atmosphere.

Controllers have picked up signal again, so we have pictures from space.

The great news is that the Ship looks very stable.

Last time, as I said, it was turning around. It had lost control of its orientation, which is super important if it’s going to present its heatshield to the oncoming rush of air as it dives down to Earth.

If the Ship can’t maintain the right attitude, it will burn up.

SpaceX founder Elon Musk has commented via his other company, X, in the last few minutes following the Starship launch.

"Successful soft landing of the Starship Super Heavy rocket booster!" he says.

Rebecca Morelle
Science editor

Image source, Reuters

For SpaceX founder Elon Musk, plans for his next generation Starship are both short and long term.

In the short term, he needs its lifting potential to service his Starlink broadband internet constellation.

Already comprising more than 6,000 spacecraft, this system requires the ongoing addition and replacement of satellites, and Starship will be responsible for this.

Down the road, Musk has talked about sending people to Mars, of making humans" a multi-planetary species".

Unsurprisingly, Starship is integral to making that dream a reality. How it could be done, no one has properly sketched out yet.

But one thing is for sure - immense lifting capacity will be needed, and a vehicle like Starship would be an essential first step.

Jonathan Amos
Science correspondent

Image source, Getty Images

While we watch the Ship section of the spacecraft cruise through the sky, let's take a look at how the SpaceX test programme's been going.

A working Starship would launch, perhaps to put satellites in orbit, and then return to Earth to sit back on the pad to prepare to go again.

But we're some way away from successfully completing all the different phases of flight. On the inaugural launch in April 2023, engine problems dogged the mission from the off.

The booster and ship failed to separate as planned and the whole structure spun out of control and was destroyed.

The second launch in November 2023 fared much better. The booster's engines worked as designed off the pad and the ship separated at the planned time. But then both segments were destroyed shortly after.

The third flight got even further into the timeline: a clean lift-off and separation, with the ship then completing its ascent to space.

Both segments were subsequently lost on their way down. But we got some spectacular imagery from the Ship in space, and as it started to heat up on re-entry, creating a hot plasma of gas around itself.

Jonathan Amos
Science correspondent

The Ship completed its powered ascent, according to the pre-planned flight profile.

It’s now in space more than 150km in altitude and moving at more than 25,000km/h. We’re now in a cruise around the globe to a re-entry point over the Indian Ocean.

What to watch? Look to see that the Ship maintains its orientation.

On the previous flight it started to roll, a behaviour that ultimately resulted in it making an uncontrolled re-entry into the atmosphere.

Additional reaction control thrusters have been added to this flight to maintain a better attitude.

Jonathan Amos
Science correspondent

Just wow.

As per the plan, the booster was brought back down to the Gulf, to hover just above the water.

It’s a big step forward from previous test flights when the booster was destroyed in flight.

This hover is a prelude to future landings on land, in which the booster will hover in front of its launch tower to be caught by the tower’s big arms.

Jonathan Amos
Science correspondent

Amazing sight on launch.

Notice, though, that one of the 33 engines shut down shortly after lift-off.

It didn’t seem to affect the ascent, however.

This is the redundancy that’s designed into the system. It can cope with some engine flame-outs.

The separation of the Ship and the booster was clean and all six of the Ship’s engines ignited.

Here we go. The giant Starship rocket has just launched from SpaceX's base in Texas.

Stick with us and don't forget to click the Play button at the top of our page to follow it live.

Jonathan Amos
Science correspondent

Image source, Reuters

The phase I'm most looking forward to - assuming the test flight gets that far - is the re-entry of the Ship into the Earth's atmosphere over the Indian Ocean.

On the last flight, the Ship could not properly control its orientation, which meant it couldn't angle its heat protection tiles efficiently to cope with the blistering temperatures that build up when a high-speed object rams into the thickening layers of air on descent.

We saw the Ship enveloped in a bright plasma as it struggled - and ultimately failed - to correct its entry attitude.

The pictures and all telemetry were lost when the vehicle had come down to roughly 65km (40 miles) in height.

For this flight, SpaceX has added more reaction thrusters to the Ship to allow it to better control its orientation. If the vehicle can make it through the most extreme moments of re-entry, it should provide us with even more spectacular imagery than we got last time.