The Russian spacewalk will come first. It’s currently planned for mid-August and will be performed by Expedition 32 Commander Gennady Padalka and Flight Engineer Yuri Malenchenko. Padalka has taken part in eight previous spacewalks, and already has a total of 27 hours and 15 minutes of time spent spacewalking. Malenchenko has performed four spacewalks that lasted a combined total of 24 hours and 14 minutes.
For the six-hour long spacewalk, Padalka will be wearing a Russian Orlan spacesuit with marked with a red stripe, while Malenchenko’s will sport a blue stripe. During the spacewalk, they will install additional micrometeoroid and orbital debris shields on the Zvezda service module and move the Strela 2 telescoping boom from the Pirs docking compartment to the Zarya control module. The boom is being moved in preparation for the arrival of the new Russian Multipurpose Laboratory Module (MLM), which will replace Pirs in 2013.
If time allows they will also retrieve two experiments from the airlock’s exterior and install two support struts for the ladder outside the Pirs hatch. The satellite is a little more than 20 inches (53 centimeters) in diameter and weighs about 20 pounds (9.2kilograms).
Flight engineers Suni Williams and Aki Hoshide will perform the U.S. spacewalk, which is tentatively set for late August. Williams, who already has four spacewalks and 29 hours and 17 minutes of spacewalking time under her belt, will be the lead spacewalker for the excursion. As such, she’ll wear the U.S. spacesuit (the extravehicular mobility unit) marked with a red stripes. Hoside, who will be performing his first spacewalk, will wear an all-white spacesuit.
Williams and Hoshide expect to stay outside the station for six-and-a-half-hour. They’ll use the time to replace one of the four Main Bus Switching Units (MBSU) that are the primary electrical power routing devices on the space station. MBSU 1 began showing preliminary indications of failure in October 2011. The unit has continued to provide power without interruption since then, but is expected to fail at some point and is being replaced to prevent unnecessary service interruptions. They’ll also route cables needed to integrate the Russian MLM with station systems. And, if time allows, they plan to install a debris and thermal cover on the Pressurized Mating Adapter 2, which served as the primary space shuttle docking port on the end of the Harmony module.