During long missions in space, one of the coolest changes to the human body is that it gets taller! This is because in the low-gravity environment in space, our spines relax and expand.
However, there are other changes that are not so cool. These include a slow loss of muscle, space sickness, lower blood pressure, and changes to the heart and lungs.
The difference in gravity between space and Earth also puts pressure on our eyes, and can cause vision problems.
All of these changes can affect an astronaut's health, both in space and after returning to Earth.
This is why it is important for scientists to study these effects on the human body - so that astronauts can continue to safely explore space.
