Astronauts May Take Surprise Spacewalk to Fix Space Station: NASA

NASA astronaut Scott Kelly is seen during a spacewalk outside the International Space Station on Nov. 6, 2015. He and crewmate Tim Kopra will likely perform a surprise spacewalk on Monday, Dec. 21, to repair the station's stuck Mobile Transporter.
NASA astronaut Scott Kelly is seen during a spacewalk outside the International Space Station on Nov. 6, 2015. He and crewmate Tim Kopra will likely perform a surprise spacewalk on Monday, Dec. 21, to repair the station's stuck Mobile Transporter. (Image credit: NASA)

Astronauts on the International Space Station will likely take an unplanned spacewalk next week to fix a stuck railcar used by the orbiting lab's robotic arm, NASA officials said today (Dec. 18).

The surprise spacewalk could occur as early as Monday (Dec. 21) and would send NASA astronauts Scott Kelly and Tim Kopra outside the space station to free the outpost's Mobile Transporter railcar, which stopped moving on Wednesday (Dec. 16) while under remote control by flight controllers on Earth. The problem must be fixed before the arrival of an unmanned Russian Progress cargo ship on Dec. 23.

NASA engineers suspect the stalled railcar is the result of a stuck brake handle, according to Kenny Todd, the station's Mission Integration and Operations Manager at NASA's Mission Control center in Houston. [How the International Space Station Works (Infographic)]

The space station's Mobile Transporter is a rail-based platform that runs much of the length of the space station's main truss, allowing the station's robotic arm to reach most of the orbiting lab. Right now, the railcar is just 4 inches (10 centimeters) from its intended latch point — near the center of the station's main truss — where it can be securely locked into place and powered ahead of the Progress cargo ship arrival.

The robotic cargo ship, called Progress 62, is scheduled to launch toward the space station from Baikonur Cosmodrome in Kazakhstan on Monday at 3:44 a.m. EST (0833 GMT). It is due to dock itself at the station two days later, on Dec. 23, at 5:31 a.m. EST (1031 GMT).

In a NASA TV interview, Todd said engineers will evaluate the stuck railcar and devise a plan to free it over the weekend. The space station management team will meet on Sunday (Dec. 20) to decide whether to go ahead with the spacewalk on Monday, or push it to Tuesday (Dec. 22). NASA will televise the spacewalk live.

The spacewalk repair should take up to 3.5 hours, Todd said.

The surprise spacewalk next week will be the 191st dedicated to space station assembly or repair. It will also be the third career spacewalk for Kelly and the second for Kopra.

The space station is currently home to six crewmembers: two Americans (Kelly and Kopra), three Russians and British astronaut Tim Peake, who represents the European Space Agency. Kopra, Peake and cosmonaut Yuri Malenchenko arrived at the space station on Tuesday (Dec. 15). They joined Kelly and cosmonauts Mikhail Kornienko and Sergey Volkov, who were already aboard.

Kelly and Kornienko are in the midst of a yearlong space mission that will end in March.

Email Tariq Malik at tmalik@space.com or follow him @tariqjmalik and Google+. Follow us @Spacedotcom, Facebook and Google+. Original article on Space.com.

Join our Space Forums to keep talking space on the latest missions, night sky and more! And if you have a news tip, correction or comment, let us know at: community@space.com.

Tariq Malik
Editor-in-Chief

Tariq is the Editor-in-Chief of Space.com and joined the team in 2001, first as an intern and staff writer, and later as an editor. He covers human spaceflight, exploration and space science, as well as skywatching and entertainment. He became Space.com's Managing Editor in 2009 and Editor-in-Chief in 2019. Before joining Space.com, Tariq was a staff reporter for The Los Angeles Times covering education and city beats in La Habra, Fullerton and Huntington Beach. In October 2022, Tariq received the Harry Kolcum Award for excellence in space reporting from the National Space Club Florida Committee. He is also an Eagle Scout (yes, he has the Space Exploration merit badge) and went to Space Camp four times as a kid and a fifth time as an adult. He has journalism degrees from the University of Southern California and New York University. You can find Tariq at Space.com and as the co-host to the This Week In Space podcast with space historian Rod Pyle on the TWiT network. To see his latest project, you can follow Tariq on Twitter @tariqjmalik.