Long-flight astronauts have atrophy of the muscles supporting the spine — and they don’t return to normal even after several weeks back on Earth, a NASA study shows. The pale blue Earth serves as a backdrop for astronaut Michael Gernhardt, who is attached to the Shuttle Endeavour’s robot arm during a spacewalk on the STS-69 mission in 1995. Unlike earlier spacewalking astronauts, Gernhardt was able to use an electronic cuff checklist, a...
