Astronaut Ed Lee conducts the first spacewalk on June 3, 1965 (Photo Credit: NASA)

Science fiction thrillers frequently feature accidents that cause astronauts to float away into space. Though this has yet to happen in the real world, it is a risk every astronaut is well-aware of when embarking on a spacewalk or Extra Vehicular Activity (EVA). To prevent the nightmare scenario, space explorers are not only tethered to the spacecraft but also fitted with a backup safety kit.