Five things you may not have known about Tim Peake’s spacewalk:

1. It had to be carried out in darkness

The two astronauts were fixing an electrical box that regulates voltage from one of the station’s solar arrays. It needed to be fixed to get the space station running back on full power.

For safety reasons, it has to be done during darkness when the solar panels are not generating power from the Sun.

Royce Renfrew, ISS spacewalk flight director, explains:

“We do it during the night pass – that way we’re absolutely guaranteed that there’s no power flowing through there, because there’s no Sun to generate any electricity.”

Tim had 31 minutes to complete the repairs. If they don’t finish in one go, they must wait for darkness in the second or third orbit of the Earth to finish the re-fit.

2. Tim needed a toothbrush

The astronauts worked together to replace the faulty component. One crucial step is bolting the new box into position. Past experience has shown that the threads of bolt can get blocked with debris – which can be removed with a toothbrush.

3. Like all spacewalks, it is a risky business

Working in the harsh environment of space is hazardous. Both astronauts have prepared for spacewalks in astronaut training but things can go wrong.  Tripping over a cable is one risk as is being hit by a small meteorite or getting a hole in your spacesuit. Spacesuits provide protection for the astronauts but their bulk can make it hard to carry out delicate tasks.

As Paul Dum, Nasa’s lead spacewalk officer, puts it:

“Spacewalking is challenging – you have to wear a spacesuit which is sort of your own independent space ship to protect you from the harshness of the environment.
“So there’s a trade off between having as much protection as possible but still maintaining mobility.
“So imagine going out with thick winter gloves on and trying to do anything that takes fine dexterity. That’s going to be challenging.”

Like rock climbers, the astronauts must always be tethered to space station supports to prevent them floating away.

4. Spacewalks are far from routine but not that rare either

There have been 191 spacewalks for maintenance at the space station, including a similar walk completed in 2014 by US astronaut Reid Wiseman.

5. There’s little time to enjoy the view

Tim Peake, writing on his blog, said he felt “exhilarated” by the prospect of walking in space, but had no time to dwell on these emotions.

British-born US astronaut Nicholas Patrick, a spacewalk veteran, said he should find time to enjoy the “majesty of the view” during his trip outside.

“You are used to floating – by this point Tim has been in space for a month, he will know exactly what floating is like – what he won’t be used to is being outside the space station with a fabulous view and, perhaps more importantly, with a very difficult set of time-critical tasks ahead of him.
“My bet is that, like me, when he goes out he won’t be looking down initially, he will be looking left and right, finding his way around and getting ready for the tasks ahead.
“But it’s a great thing to go out, it’s really a wonderful experience.”