NASA Astronauts Whitson and Fischer Conduct 200th Spacewalk at the ISS

NASA Astronauts Whitson and Fischer Conduct 200th Spacewalk at the ISS

Whitson and Fischer's walk in space marks the 200th spacewalk on the International Space Station. App users can tune in here.

Expedition 51 Flight Engineer Jack Fischer of NASA is seen inside the International Space Station (ISS) in his spacesuit during a fit check, in preparation for a spacewalk on Friday, May 12.

When compared with the relative safety of living and working inside the Space Station, floating around in space with only a tether to keep you firmly attached to your home above Earth isn't exactly a super safe position.

The pair will move through the Quest airlock to replace an avionics box used for science experiments, while also installing a connector to route data through the alpha magnetic spectrometer.

Spacewalks usually last about six and a half hours, but Friday's would be "abbreviated" due to the late start and would last about four hours, Navias said.

Playing it safe, flight controllers at the Johnson Space Center made a decision to shorten the spacewalk to four hours and to eliminate all tasks other than the highest priority item, replacement of a 200-pound avionics box on an external logistics platform.

"It has been exhibiting some thermal issues of late, so it is being replaced", he said. The 57-year-old Whitson has also spent more days off the planet than any other woman (more than 500 days in total) and will be recognizable by the red stripes on her space suit.

Today's spacewalk builds on a historic career for Peggy Whitson.

After the first three minutes the fuel ran out and White maneuvered by twisting his body and pulling on the tether. NASA TV coverage begins at 5:30 AM CDT.

The umbilical is not part of the spacesuit, NASA said, but is a piece of support equipment inside the space station.

"Only because of legends like Peggy, and Jerry Ross and [Jim] Newman [who took that first station spacewalk] and the guys who started this, that made this possible", Fischer replied.