Spacewalks

A spacesuit is much more than a set of clothes astronauts wear on spacewalks. A fully equipped spacesuit is really a one-person spacecraft.

NASA's first spacewalks took place during the Gemini program.

The world record for the most spacewalks is held by Russian astronaut Anatoly Solovyev with a total of 16 EVAs and more than 82 hours outside in space.

Spacesuits protect astronauts from extreme hot and cold temperatures, harmful space dust and radiation. They also give astronauts oxygen to breathe and water to drink during spacewalks.

Astronauts prepare for spacewalks by practicing their tasks underwater in a giant pool called NASA's Neutral Buoyancy Laboratory.

Spacewalks usually last between five and eight hours, depending on the job.

Sometimes a large robotic arm is used to move astronauts on spacewalks. Astronauts are attached to the robotic arm using a foot restraint.

Cassidy and fellow astronaut Bob Behnken have conducted the first of at least four spacewalks to replace the last in series of old nickel-hydrogen batteries with new, more efficient lithium-ion batteries.

Astronauts from the U.S. space shuttle Atlantis are now halfway through the four spacewalks needed to mount the truss and string cables through it.

The seven-member crew made unprecedented upgrades and repairs to the telescope during five ambitious spacewalks in what was an especially dangerous mission because of debris cluttering the orbit.