Spacewalkers fix robotic arm in time to grab next cargo ship

Miami:  Two American astronauts on October 20 wrapped up crucial repairs to the International Space Station's robotic arm, with just weeks to spare before the next cargo ship arrives in early November, NASA said.

During a six hour, 49 minute spacewalk, NASA's Joe Acaba and Randy Bresnik put the finishing touches on repairs to the Canadian-made 57-foot (17-metre) long arm, called Canadarm 2.

The arm has been a key piece of equipment at the orbiting outpost for 16 years, but in August it lost its ability to grip effectively.

Astronauts inside the station maneuver the external arm to latch on to incoming spaceships that are packed with food and supplies for the rotating crew of six living in low-Earth orbit. It is also used to move equipment and people around outside the space station.

The next US supply shipment, delivered on an unmanned Cygnus cargo ship launched by Orbital ATK, is expected to arrive November 13.

In a rush to get the repairs done before then, NASA organized a rapid-fire succession of three spacewalks in three weeks — October 5, October 10 and October 20.

During Friday's outing, astronauts replaced a poorly focusing camera system at the end of the robotic arm -- necessary to get a good view of the approaching cargo ships -- and fixed a fuse on the robotic arm's extension, called Dextre.

They also installed another new high definition video camera outside the ISS.

The robotic arm's hand, officially called the latching end effector, was replaced during the October 5 spacewalk.

Astronauts lubricated the arm on the October 10 spacewalk, and a new high definition video camera was also installed outside the research lab.

Friday's spacewalk was the 205th in the history of the space station, an international collaboration involving more than a dozen countries.

There have been 10 spacewalks so far this year to repair and maintain the ISS, with nine outings by NASA and one by Russian cosmonauts.

Bresnik, 50, a former Marine Corps aviator who goes by the nickname "Komrade," has led all three of the October spacewalks, and made his fifth career excursion outside the space station Friday.

His colleague Acaba, 50, is the first person of Puerto Rican heritage to become an astronaut, according to his NASA biography.

The former hydro-geologist and educator became an astronaut in 2004 and spacewalked twice in 2009 during the space shuttle era.