Spacewalk Scrap: ISS Astronauts Toss Space Junk
This view, taken from the spacesuit helmet camera of Expedition 15 commander Fyodor Yurchikhin, shows NASA astronaut Clayton Anderson in his own red-striped spacesuit, with space station solar arrays and a thin blue arc of the Earth's horizon in the background, during a July 23, 2007 spacewalk.
Credit: NASA TV.

This story was updated at 5:11 p.m. EDT.

With a big lean back and a giant push forward, American astronaut Clayton Anderson heaved a 1,400-pound (635-kilogram) tank of ammonia from the International Space Station today (ISS).

"Jettison!" Anderson shouted shortly after tossing the unneeded refrigerator-sized container from the robotic arm of the station.

The junking of equipment was one of two today during the seven-hour-and-41-minute spacewalk that began at about 200 miles above the Earth. Cosmonaut Fyodor Yurchikhin joined Anderson outside, while cosmonaut Oleg Kotov maneuvered the station's Canadian-built robotic arm around with Anderson on the end.

"This is the first day and the first time a Russian cosmonaut has operated, in orbit, the [station's] robotic arm," Anderson said, adding his appreciation for Yurchikhin's participation. "I'm very appreciative of their work."

"Fyodor, come outside and play," Anderson told Yurchikhin once he emerged from the U.S. Unity module's airlock at 6:24 a.m. (1024) GMT, officially beginning the spacewalk.

Time to jettison

Once outside, Anderson and Yurchikhin began installing a video stanchion, or support frame, on one of the station's trusses. The equipment will be used to hold a video camera that will assist with future expansion of the ISS.

The two then separated, with Yurchikhin replacing a failed circuit breaker for the station's truss-based rail car system, and Anderson disconnecting cabling hooked up to the tank of unneeded ammonia coolant.

"Our spaceship Earth is a beautiful place," Anderson said while describing his view outside of the growing international laboratory.

Around 8:55 a.m. EDT (1255 GMT), Anderson snapped into the foothold on the space station's robotic arm, then moved out into space with 212 pounds (96 kilograms) of flight support equipment that previously held the stanchion into place.

Using a maneuver practiced back on Earth, Anderson leaned back, then forward and gave the equipment a mighty push into space.

"It looks pretty cool, like a huge star, and the brightness of it changes as it rotates," Anderson said of the careening hunk of equipment, which he threw more than 1 foot (30 cm) per second. He then joked about the success of the throw.

"I'll be sending my bill in the mail for garbage disposal," he told mission control in at Johnson Space Center in Houston, Texas following the jettison. NASA expects the object to burn up in the Earth's atmosphere within 330 days.

Yurchikhin then assisted Anderson with disconnecting the second junked equipment, this time the 1,400-pound (635-kilogram) backup reservoir of ammonia. NASA said in several briefings that the tank had reached the "end of its life," as far as its structural integrity was concerned, and was no longer needed on the ISS. Discarding the equipment also helped clear the station’s mast-like Port 6 truss for relocation later this year, mission managers have said.

After the big toss, Anderson requested that mission control call his family and tell them he "just threw a 17,500-mile-an-hour fastball."

NASA will keep a close watch on the adrift ammonia tank and video camera stanchion support frame as they spiral towards Earth to ensure they don’t post a risk to the ISS or other spacecraft. Mission managers plan to boost the space station’s orbit later tonight to provide extra clearance and ready the orbital laboratory for the arrival of an unmanned Russian cargo ship and NASA’s Endeavour shuttle crew next month.

Extra innings

After the dangerous task of tossing space junk was complete, the astronauts began work on other projects.

Yurchikhin moved to the Unity module, where he enlisted a scraping device to clean off spots of grime which had stuck to a common berthing mechanism (CBM), or fine silicon seal.

"There's a lot of debris there," Yurchikhin said as he scraped the grit away. The cosmonaut described the material as an oily substance mixed with bits of hair and possibly paper. "It just spreads everywhere."

The cleaned seal will ensure an airtight connection when the station’s Expedition 15 crew moves a pressurized mating adapter later this year.

While Yurchikhin cleaned, Anderson maneuvered himself off of the robotic arm and removed a faulty global positioning satellite (GPS) antenna outside of the space station.

"One GPS is in the bag," Anderson said after unbolting the basketball-sized device, which is one of four on the ISS. The project came as an addition to the check-list, as the both astronauts made good time in completing their tasks.

As the spacewalk neared its end, Yurchikhin began to clean up and look for stray tools and bags of equipment. Meanwhile, mission control instructed Anderson to loosen some bolts in preparation for future expansion of the space station.

Both astronauts climbed inside the airlock and closed the hatch at about 2:06 p.m. EDT (1604 GMT), making for a total spacewalk time of seven hours and 41 minutes. The spacewalk marked Anderson's first time outside the ISS and Yurchikhin's third.

"We truly thank you for your perfect execution," mission control said shortly before the hatch closed.