Related topics: international space station

'New port of call' installed at space station

With more private spaceship traffic expected at the International Space Station in the coming years, two spacewalking US astronauts installed a special parking spot for them on Friday.

NASA releases new imagery of asteroid mission

( —NASA released Thursday new photos and video animations depicting the agency's planned mission to find, capture, redirect, and study a near-Earth asteroid. The images depict crew operations including the Orion ...

Space station gets room, huge window to see Earth

(AP) -- Astronauts put the last big addition on the International Space Station early Friday, attaching a new room with an enormous bay window that promises to provide unprecedented panoramic views of Earth.

China's space program shoots for moon, Mars, Venus

This year, a rocket will carry a boxcar-sized module into orbit, the first building block for a Chinese space station. Around 2013, China plans to launch a lunar probe that will set a rover loose on the moon. It wants to ...

Robot assembles truss structures autonomously

( -- Like something straight out of "Star Wars," armies of robots could nimbly be crawling up towers and skyscrapers to make repairs in the not-so-distant future, so humans don't have to.

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Extra-vehicular activity

Extra-vehicular activity (EVA) is work done by an astronaut away from the Earth, and outside of a spacecraft. The term most commonly applies to an EVA made outside a craft orbiting Earth (a spacewalk), but also applies to an EVA made on the surface of the Moon (a moonwalk). In the later lunar landing missions (Apollo 15, 16, and 17) the command module pilot (CMP) did an EVA to retrieve film canisters on the return trip; he was assisted by the lunar module pilot (LMP) who remained at the open CM hatch. These trans-Earth EVAs were the only spacewalks ever conducted in deep space.

Due to the different designs of the early spacecraft, the American and Soviet space programs also define an EVA differently. Russians define an EVA as occurring when a cosmonaut is in a vacuum. An American EVA begins when the astronaut switches the Extravehicular Mobility Unit (EMU) to battery power. A "Stand-up" EVA (SEVA) is where the astronaut does not fully exit a spacecraft, but is completely reliant on the spacesuit for environmental support. Its name derives from the astronaut "standing up" in the open hatch, usually to film or assist a spacewalking astronaut.

EVAs may be either tethered (the astronaut is connected to the spacecraft, oxygen can be supplied through a tube, no propulsion is needed to return to the spacecraft) or untethered. When the tether performs life support functions such as providing oxygen, it is called an umbilical. Untethered spacewalks were only performed on three missions in 1984 using the Manned Maneuvering Unit (MMU), and on a flight test in 1994 of the Simplified Aid for EVA Rescue (SAFER). A SAFER is a safety device worn on tethered U.S. EVAs, since the capability of returning to the spacecraft is essential.

As of 2009[update], Russia, the United States, and China are the only countries with a demonstrated capability to conduct an EVA.

This text uses material from Wikipedia, licensed under CC BY-SA