Station Astronauts Conducting Spacewalk JULY 9 2013

Two Expedition 36 astronauts are venturing outside the International Space Station Tuesday on the first of two July spacewalks to prepare the orbiting complex for a new Russian module and perform additional installations on the station’s backbone.
Flight Engineers Chris Cassidy of NASA and Luca Parmitano of the European Space Agency switched their spacesuits to battery power at 8:02 a.m. EDT, signalling the start of Tuesday's 6 1/2 hour spacewalk from the Quest airlock.  NASA Television is proving live coverage of the excursion.




                                                    After the two spacewalkers exit the hatch, Cassidy will move to the top of the Z1 truss to remove and replace a Space-to-Ground Transmitter Receiver Controller.  This unit, one of two that allows for two independent strings of Ku-band communication for video and data, failed in December 2012.
In parallel to this, Parmitano will head out to the Express Logistics Carrier-2 on the starboard truss segment and retrieve two experiments that were part of the Materials International Space Station Experiment-8, or MISSE-8.  The Optical Reflector Materials Experiment III (ORMatE-III) and the Payload Experiment Container, which assessed the impacts of the space environment on materials and processor elements, are scheduled to return to Earth aboard the SpaceX-3 commercial cargo craft later this year.


                                                                                                                                                    source:nasa