Despite the ever-present risks related to mechanical failures while working in open space, no spacewalking astronaut has ever been lost. There is a requirement for spacewalking astronauts to use tethers and sometimes supplementary anchors. If those fail, a spacewalking astronaut would most probably float away impelled by forces that were acting on the astronaut at the time of breaking loose. Such an astronaut would possibly be spinning, as kicking and flailing would be of no use. At the right angle and velocity, the astronaut might even re-enter the Earth's atmosphere and burn up. NASA has protocols for such situations: astronauts would be wearing an emergency jetpack that would automatically counter any tumbling. NASA's plan states that astronauts should then take manual control of the jetpack and fly back to safety.