Only about 600 people have ever traveled to space. The vast majority of astronauts over the past six decades have been middle-aged men on short-duration missions of fewer than 20 days. Only about 600 people have ever traveled to space. The vast majority of astronauts over the past six decades have been middle-aged men on short-duration missions of fewer than 20 days. Space Exploration Phys.org – latest science and technology news stories
A new set of studies offers the most comprehensive look at spaceflight health since NASA’s Twins Study
