Ed White was the first American to perform a space walk. Photo courtesy of NASA

How do Astronauts Walk in Space?
The term "space walk" is somewhat misleading because astronauts float in space. Note that the formal name for a space walk is Extravehicular Activity (EVA).
Imagine a spacecraft orbiting the Earth at 200 miles altitude. The speed of the spacecraft would be about 18,000 miles per hour. The astronauts inside the spacecraft are in a state of "apparent weightlessness." Basically, the astronauts float, whether they are inside or outside the spacecraft. Sometimes the astronauts use seat belts, foot restraints, and other devices to keep their bodies still so that they can perform work tasks when they are inside the spacecraft.
An astronaut who is preparing for a "space walk" must wear a pressure suit because there is virtually no air pressure at 200 miles altitude. The astronaut must also have an oxygen supply for breathing.
One method is for the astronaut to remain connected to the spacecraft through an "umbilical hose." This hose supplies the astronaut with oxygen. This is the method which Ed White used when he became the first American astronaut to make a space walk in 1965. Ed White's umbilical hose also had radio wires so that he could communicate with astronaut Jim McDivitt, who remained inside the Gemini spacecraft.
Astronauts also need some means of propulsion when they make an EVA. Ed White used a handheld maneuvering unit to propel himself. This unit shot out short bursts of nitrogen gas.
Space shuttle astronauts can use a Manned Maneuvering Unit (MMU) for EVAs. This system allows the astronaut to move about without being tethered to the spacecraft. This system use compressed nitrogen gas to propel the astronaut. The astronauts controls the gas burst using a joystick. This system also has an oxygen supply for the astronaut.
Who was the first person to perform a space walk?
Soviet cosmonaut Aleksei Leonov made the first space walk during the Voskhod II mission on March 18, 1965. He performed this above Siberia.

Leonov was also one of the cosmonauts in the Apollo-Soyuz mission in 1975.
Who was the first American to perform a space walk?
The first American to perform a space walk was Ed White in June 1965. He flew in the Gemini IV mission along with James McDivitt. White began his space walk while the spacecraft was over the Indian Ocean. He continued his walk over the Pacific Ocean.

Astronaut White died in the Apollo 1 fire in 1967. This fire occurred during a training session at the launch pad.
Who was the first woman to perform a space walk?
The first woman to perform a space walk was Soviet cosmonaut Svetlana Savitskaya during the Soyuz T-12 mission in July 1984.

Cosmonaut Savitskaya was also the second woman in space, achieving this distinction on the Soyuz T-7 mission in 1982.
Who was the first American woman to perform a space walk?
Dr. Kathyrn Sullivan became the first American woman to perform a space walk. She did this on the STS-41G Space Shuttle Challenger mission in October 1984.

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