NASA astronaut Randy Bresnik tweeted this amazing picture aboard the International Space Station of cosmonauts Fyodor Yurchikhin and Sergey Ryazanskiy writing, "As the sun rose on our Russian crew’s 7.5 hr spacewalk, their helmets lights gave off a glow that made it look like they were underwater…" Did you know our NASA astronauts actually train for long space walks like this one underwater at the Neutral Buoyancy Laboratory near NASA's Johnson Space Center? Credit: NASA/astrokomrade #NASA #spacewalk #iss #cosmonauts #nbl #explore