Going to space is a dangerous endeavour. The deeper you go, the riskier it becomes.
As you might expect, putting a human designed for Earth's environment into an atmosphere devoid of his or her necessities can have many consequences.
NASA identified five risks for longer spaceflight: radiation, isolation, distance from Earth, gravity, and hostile environments.
Astronauts are subjected to rigorous training regimens and team-building exercises in order to deal with these risks.
Astronauts are subjected to significant amounts of space radiation, also known as ionising radiation.
According to NASA, the exact amount they are exposed to ranges from 50 to 2,000 mSv, or Milli-Sievert.
NASA has worked in a variety of ways to combat this. NASA's Human Research Program created the acronym CONNECT to assist astronauts in remembering it during their mission.