Ground control to Major Tim

By now, at the time of writing, Major Tim Peake is on day 105 of his mission on the International Space Station (ISS). The main reason for his expedition is to perform a number of scientific experiments under the effect of weightlessness, as well as collecting samples from his own body for studies here on earth. He's blown into lung–function kits, collected blood, stool and urine samples, measured properties of his skin, given himself ultrasounds, conducted eye examinations and completed numerous health questionnaires, just to name a few!