April 12th marked the 49th anniversary of human spaceflight, when Yuri Gagarin became the first person to orbit the Earth in 1961. At this moment, 13 humans are currently in low-Earth orbit, aboard the International Space Station. Several were already aboard the ISS when a Soyuz TMA-18 brought a fresh crew up from the Baikonur Cosmodrome on April 2nd - they were later joined by the crew of the Spa