Backyard Skywatchers Find Tool Bag Lost in Space
An equipment bag drifts away from spacewalker Heide Stefanyshyn-Piper as she works on a solar array gear during a Nov.18, 2008 spacewalk outside the International Space Station.
Credit: NASA TV.

Amateur astronomers have been monitoring a shiny tool bag that has been orbiting Earth ever since it was dropped last week by an astronaut during a spacewalk outside the International Space Station.

The bag is reportedly about magnitude 6.4, which under most sky conditions is too faint to see with the naked eye.

Veteran spacewalker and Endeavor astronaut Heide Stefanyshyn-Piper lost her grip on the backpack-sized bag on Nov. 18 while cleaning up a mess from a leaking grease gun she was carrying to help mop up metal grit from inside a massive gear that turns the space station's starboard solar wings.

The tool bag cost $100,000 and its loss meant astronauts had to share the remaining tool bag for subsequent spacewalks. The tool bag weighs about 30 pounds (14 kg) and is 20 inches (51 cm) wide, about a foot (30 cm) tall and a hand's-width deep, according to John Ray, STS-126 lead spacewalk officer for the flight. The bag contained two grease guns, a scraper tool, a large trash bag and a small debris bag.

Once the tool bag floated away, some thought they'd seen the end of it. Not quite. A satellite tracker at Spaceweather.com now is monitoring both the space station and the tool bag.

After sunset on Nov. 22, Edward Light, using 10 x 50 binoculars, spotted the bag in space while he scanned the sky from his backyard in Lakewood, N.J., Spaceweather.com reported. On the same night, Keven Fetter of Brockville, Ontario, video-recorded the bag as it passed by the star Eta Pisces in the constellation Pisces.

More bag-viewing opportunities are expected.

The tool bag can be seen through binoculars, a few minutes ahead of the space station's orbit. The satellite tracker predicts that the bag will be visible through binoculars from Europe and western North America during a series of passes this week. By late next week, the tool bag should appear in the evening skies over most of North America.

Like other space debris, the tool bag's show will have a fiery end. "We currently predict that the errant tool bag will fall back to Earth in June of next year," said Nicholas Johnson, chief scientist for orbital debris at NASA's Johnson Space Center in Houston. "The date is dependent upon solar activity, so an earlier or later date is possible. As the reentry date draws nearer, a more accurate prediction can be made."

And he expects the entire tool bag will burn up upon reentry. "Although we have not yet conducted a detailed reentry survivability analysis for the tool bag and its contents, it is highly likely that no components will reach the surface of the Earth," Johnson told SPACE.com.

The tool bag is not the only piece of space trash from the station. Other junk includes an unmanned Russian cargo ship and a massive ammonia coolant tank the size of a refrigerator. The coolant tank was intentionally tossed from the space station in 2007, and it burned up in Earth's atmosphere earlier this month. The cargo ship undocked on Nov. 14, but will loiter in orbit for engineering tests before its planned disposal in Earth's atmosphere in early December.

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