Space Station Astronauts Set for Spacewalk

Two astronauts will step outside the International Space Station tonight to add new experiments to the orbiting laboratory?s hull, including one to aid an ongoing investigation into recent Russian Soyuz spacecraft glitches.

Space station commander Michael Fincke of NASA and Russian cosmonaut Yury Lonchakov are due to float outside the station in Russian-built Orlan spacesuits at about 7:10 p.m. EDT (0010 GMT) and spend just over six hours working outside.

?I will go out the door first,? Fincke said in a video message last week. ?It?s going to be very exciting.?

Their first task is the installation of a Langmuir probe, an instrument that will monitor the plasma environment near a Soyuz docking port on the station?s Russian-built Pirs docking compartment.

The tool is designed to give engineers in Russia more information on the plasma environment near the docking port, which is suspected to be responsible for explosive bolt malfunctions on two of the last three Soyuz spacecraft to return astronauts from the space station. Russian engineers believe electrical arcs near one of the bolt locations caused it to fail during module separation on those landings, which sent the Soyuz vehicles to land off-target and subjected their crews to higher gravitational loads.

?This actual task was added as a direct consequence to the commission to understand exactly what happened with the Soyuz,? said Kirk Shireman, NASA?s deputy space station program manager.

In addition to the plasma probe, Lonchakov and Fincke will attach two experiments, EXPOSE-R and Impuls to the exterior to of the station?s Russian Zvezda module.

The EXPOSE-R experiment is a joint project between the European Space Agency and Russia?s Federal Space Agency to understand how organic materials behave in the vacuum of space. The Impuls experiment is a tool aimed at studying the plasma environment of Earth?s ionosphere.

?This [spacewalk] is going to expand our science capability,? said space station flight director David Korth.

Lonchakov and Fincke also plan to retrieve a canister-like Biorisk container filled bacteria and fungi as part of a study on how changes in solar activity affect their growth.

Flight controllers also want the astronauts to close a loose insulation flap and reposition a misaligned space exposure experiment. If extra time is available, the astronauts may also conduct a photo survey of the space station?s Russian segment with a focus on a navigation antenna that failed to work properly during a recent cargo ship?s arrival.

Today?s work outside the space station will be led by Lonchakov, who will make his first spacewalk. It will be the fifth spacewalk for Fincke, who is commanding the space station?s Expedition 18 mission. Their third crewmate, NASA astronaut Sandra Magnus, will remain inside the space station during the spacewalk.

Fincke said he was looking forward to trying out the new helmet lights for his Russian-built Orlan spacesuit, which he emblazoned with an American flag shoulder patch.

?I?m proud to be an American working on station and it?s really cool working with the Russian partners,? Fincke said last week. ?I?m glad they trust me with one of their suits to help out with the plan.?

NASA will broadcast tonight?s spacewalk live on NASA TV beginning at 6:30 p.m. EDT (2330 GMT). Click here for a link to SPACE.com?s NASA TV feed and International Space Station mission updates.

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