NASA astronaut Sunita Williams, Expedition 32 flight engineer, appears to touch the bright sun during the mission’s third session of extravehicular activity (EVA) on Sept. 5, 2012.
Astronaut Ed White performed the first American spacewalk during the Gemini 4 mission on June 3, 1965. It lasted 23 minutes.
Ed White during his historic spacewalk.
Bruce McCandless II ventured farther away from the confines and safety of his ship than any previous astronaut ever has. This space first was made possible by the Manned Manuevering Unit or MMU, a nitrogen jet propelled backpack. After a series of test maneuvers inside and above Challenger's payload bay, McCandless went "free-flying" to a distance of 320 feet away from the orbiter (1984).
Astronaut Bruce McCandless conducts a spacewalk using a jet pack called the Manned Maneuvering Unit (MMU) in 1984. He is 320 feet from the orbiter.
Astronaut Stephen K. Robinson, STS-114 mission specialist, anchored to a foot restraint on the International Space Station’s Canadarm2, participates in the mission’s third session of extravehicular activity (2005).
Astronaut Jack Lousma helped install a solar shield on the Skylab space station in 1973. The shield protected part of Skylab from the sun's heat. Look closely in Lousma's helmet to see a reflection of Earth.
Astronauts Richard Hieb, Thomas Akers and Pierre Thuot (left to right) pull a satellite into the space shuttle's cargo bay for repairs in 1992. The STS-49 mission was the first time three astronauts went on a spacewalk together.
Astronauts Bernard Harris Jr. (right), and Michael Foale (left) get ready to go on a spacewalk in the airlock of space shuttle Discovery in 1994. Harris was the first African-American to walk in space.
Astronaut Carl Meade (left) wears the backpack called SAFER, which could be used to move an astronaut back to the spacecraft after becoming untethered. Astronaut Mark Lee stands connected to the space shuttle robotic arm in 1994.
Astronaut James Newman waves at the camera in 1998. He is holding on to a handrail of the Unity connecting module of the space station. His spacewalk lasted 7 hours and 21 minutes.
Astronauts prepare for spacewalks in the Neutral Buoyancy Lab. Here, a crew member prepares to work inside of a Hubble telescope mock-up.
Astronaut Scott Parazynski smiles as he peeks into the Destiny Laboratory window on the ISS in 2001.
Astronaut John Herrington is suited up and ready to leave the airlock to begin a spacewalk on the ISS in 2002. Herrington was the first Native American to walk in space.
Astronaut Chris Hadfield "dangles upside down" in the shadow of the International Space Station in 2003.
Astronaut Joseph Tanner's Kevlar tether line is pulled tightly as he moves outside the ISS in 2006.
Astronaut Scott Parazynski moves toward a tear in one of the space station's solar array blankets in 2007. He is attached to the end of the Orbiter Boom Sensor System, or OBSS.
Astronaut Michael Lopez-Alegria holds the American record for the amount of time spent walking in space. He has performed 10 spacewalks totaling 67 hours and 40 minutes. He was also named the first Hispanic astronaut to perform a spacewalk in 2007.
Astronaut Peggy Whitson holds the world record for the woman with the most spacewalks, with a total of five. This record was set while Whitson was the commander of Expedition 16 in 2007.
Expedition 16 flight engineer Daniel Tani smiles while participating in an extravehicular activity outside the ISS in 2008.
Astronaut Rick Linnehan can be seen through a window on space shuttle Endeavour's flight deck in 2008.
STS-123 mission specialist Rick Linnehan takes a picture during the mission's third spacewalk in 2008.
Astronaut Dave Wolf prepares to enter the airlock on the ISS in 2009. Astronaut Christopher Cassidy's feet and backpack are also visible.