Successful ISS Spacewalk
July 9, 2013

Astronauts Successfully Complete 6-Hour ISS Spacewalk

[ Watch the Video: Grab Bag of Tasks Performed During ISS Spacewalk ]

Lee Rannals for - Your Universe Online

Astronauts aboard the International Space Station (ISS) completed a spacewalk on Tuesday, during which they performed routine maintenance on the orbiting laboratory.

The two astronauts completing the zero-gravity tune-up began their venture into space at 8:02 a.m. EDT as they switched their spacesuits to battery power.

Flight Engineers Chris Cassidy of NASA and Luca Parmitano of the European Space Agency (ESA) completed the successful 6-hour, 7-minute spacewalk at 2:09 p.m. on Tuesday. This spacewalk was the first of two July excursions aimed at preparing the ISS for a new Russian module and performing additional installations on the station's backbone.

Cassidy now has a total of 29 hours, 42 minutes of spacewalking time to his credit, while Parmitano completed his first-ever spacewalk. NASA said that Tuesday's spacewalk was the 170th in support of station assembly and maintenance, totaling 1,073 hours and 50 minutes.

During his first space walk, Parmitano was able to perform important maintenance outside the space station. These duties included retrieving two experiments that were part of the Materials International Space Station Experiment-8 (MISSE-8); photographing the Alpha Magnetic Spectrometer-02 (AMS-02); helping Cassidy remove two Radiator Grapple Bars (RGBs). He then installed one of them on the port side truss and the other on the starboard side. Parmitano also was able to ride the Canada2 robotic arm from the starboard side to the port side in order to remove a failed camera assembly.

The RGBs which were delivered to the space station aboard the second SpaceX Dragon mission, are intended to help remove and replace failed thermal radiators.

Meanwhile, Cassidy spent his time in space routing power cables to support the upcoming addition of the new Russian Multipurpose Laboratory Module. He also removed and replaced a Space-to-Ground Transmitter Receiver Controller, which allows for two independent strings of Ku-band communication for video and data. This controller had stopped working in December of last year.

NASA said Cassidy began the installation of two Z1 truss Y-bypass jumpers to provide power redundancy and stability for critical station components. This installation will be completed during the upcoming July 16 spacewalk. These jumpers will allow the team to quickly regain critical loads without the need to commit to a spacewalk in the event of a loss of one of the external power modules.