Elon Musk promises toilet upgrades after Inspiration4 crew faced 'challenges'

Inspiration4, the first space mission to send an all-civilian crew into Earth's orbit, landed safely on Sunday after a successful three day mission - but things on board didn't always go to plan.

SpaceX CEO Elon Musk revealed on Twitter the four astronauts had some "challenges" with the toilet system on board the crew's Dragon spacecraft.

He didn't go into details - probably a good idea when it comes to toilets in zero gravity - instead promising it would be "upgraded" for the next flight.

That response came after tweeting he had met with the Inspiration4 astronauts to congratulate them in person, calling them "great people".

He had previously admonished US President Joe Biden after being asked by a Twitter user why Biden hadn't acknowledged the astronauts.

Musk replied: "He’s still sleeping", echoing former President Trump's "sleepy Joe" nickname for the man who beat him in the 2020 US election.

The billionaire also promised WiFi from his StarLink satellites for future astronauts, along with a little oven for heating food.

The latter was a reference to Sian Proctor, a geoscientist and science communicator on board Inspiration4, who took cold pizza to space. 

"[It] better be packed, because that was my order," she told a media event prior to take-off.

"You know, food and mood is so important. I think for us, it was really important working with SpaceX to get food that made us feel comfortable and that we could eat."

The toilet system on board the Dragon spaceship remains a secret, with Business Insider reporting previous questions about it have been ignored due to its proprietary nature.

But one thing that is known is its location. It's on the ceiling in an area that also features a large glass dome, meaning the astronauts are able to look out the window while using the facilities.

Billionaire entrepreneur Jared Isaacman, the commander of the mission, previously said there wasn't a lot of privacy involved in using the toilet.

"But you do have this kind of privacy curtain that cuts across the top of the spacecraft, so you can kind of separate yourself from everyone else," he told Business Insider.

"And that also happens to be where the glass cupola is. So, you know, when people do inevitably have to use the bathroom, they’re going to have one hell of a view."