The space agency announced that two American astronauts will perform a six-and-a-half-hour spacewalk on Saturday instead of today to begin assembly of two new docking stations on the orbiter. The spacewalk is scheduled to begin at 7:10 a.m. ET.
The delay is so "added analysis" can be done on the spacesuits that NASA astronauts Commander Barry "Butch" Wilmore and Flight Engineer Terry Virts will wear during their spacewalk.
This isn't the first time that spacesuits have delayed the beginning of work on the space docks.
Dan Huot, a NASA spokesman, said the spacewalk initially had been set for early last month but was pushed back so ground teams could analyze two fan pump separators, which control the temperature in the suits, that exhibited start-up issues.
The spacewalk, which had been scheduled for today, was pushed back 24 hours for final testing.
"The suits currently on board and their fan pumps have been thoroughly tested and teams are confident in their performance," Huot said. "The 24-hour delay this week was just to give teams the time to close out final paper work and make sure everything was ready to go."
The space agency, working with other international partners, is trying to add two new space docks to the orbiting station to handle what is expected to be an increasing number of commercial space taxis bringing supplies and astronauts to the station.
NASA is expected to stop paying Russia to ferry its astronauts to the space station in 2017. The agency contracted with SpaceX, which already conducts resupply missions, and Boeing to launch astronauts from U.S. soil for the first time since NASA retired its fleet of space shuttles in 2011.
Two other spacewalks -- one on Wednesday and another on March 1 -- have been set up to continue work on the new space docks.
NASA TV is scheduled to begin coverage of Saturday's spacewalk at 6 a.m.
The delay for additional scrutiny of the spacesuit comes about a year and a half after an astronaut from the European Space Agency nearly drowned because of a leak in his suit.
Water began leaking into the suit that Luca Parmitano, an Italian astronaut with the European Space Agency, was wearing during a spacewalk in July 2013.
NASA reported at the time that the leak didn't pose an immediate danger to Parmitano, but the astronaut noted the harrowing experience in a blog post .