Question: What does it look like in a human body when its been in space?

Kirsty Lindsay answered on 13 Jun 2016:

What a great question- I really had to think how to answer!

What a body looks like on the inside really depends on how you look at it, and where you look. If we could look inside someone using our eyes they would look pretty much the same after a space mission than before- kind of red and squishy!

If we looked using a special machine to measure bone density- called a DEXA machine, the astronauts bones in their legs would look much thinner and would have more holes in the middle like a sponge- they would look less dense. This is because in space we loose more of the minerals that build bones, and we aren’t as good at repairing our bones in space.

If we looked inside an astronaut with an MRI machine- which is a great big magnet connected to a computer so we can see pictures- the astronaut would have less muscles, and the muscles would be more fatty. In space, because they don’t have to work as hard, muscles become weak, and they get smaller. This is really obvious in the astronauts legs. Astronauts do exercise every day to try and stop their muscles getting weaker- it’s like having a PE class for 2 hours every day.