Question

why do astronauts need spacesuits In The Exosphereand beyond?

Answer 1

Let me give you a detailed explanation on this :

Exosphere is a thin atmospheric layer around Earth where all the atoms/molecules/particles are bound to have a gravitational attraction.

Now to answer your question Astronauts do need spacesuits beyond the Exosphere because :

1) There is 100% vaccum above the Exosphere. So first of all this makes completely no air or oxygen to breathe.

2) No Gravitation pull so they need thrusters to move around the universe or in their space stations.

3) There is completely no pressure so their bodies would blast out of their inner blood pressure.

These were the most important points for your wonderful question.

Thank you