Astronaut's Lost Tool Bag Worth About $100,000

A tool bag that floated away from a spacewalking astronaut this week was one of the largest items ever lost in space, and NASA guessed it cost about $100,000.

Astronauts vowed to double-check, even triple-check, to make sure a second bag of tools is properly tied down during a spacewalk today.

"We're definitely not going to do it again. You're not going to see us lose another bag," lead spacewalker Heidemarie Stefanyshyn-Piper said in an interview from the international space station with The Associated Press.

During the two-week mission's first spacewalk Tuesday, the tool tote floated out of a larger bag as Stefanyshyn-Piper cleaned grease from a leaking grease gun. Tethered to the lost briefcase-sized bag were a pair of grease guns used to lubricate a jammed joint that controls the space station's rotating solar wing.

The mishap left Stefanyshyn-Piper and her fellow spacewalkers, Stephen Bowen and Robert "Shane" Kimbrough, with only a single pair of grease guns for three more spacewalks.

"We're going to double- and triple-check everything from here on out," Stefanyshyn-Piper said.

Today's spacewalk is almost identical to the earlier one, except Stefanyshyn-Piper will have Kimbrough as a partner instead of Bowen. The spacewalkers, some 220 miles above Earth, plan to clean and lubricate the troublesome joint. They also plan to relocate a railcar used on the space station's exterior rail track and lubricate the end of the station's robotic arm.

Some changes were made to the spacewalk plans because of the missing grease guns.

The remaining pair of grease guns will be tethered to a larger bag so they won't leak on other equipment. A dry wipe will be wrapped around the grease guns to catch any leaks. Finally, Stefanyshyn-Piper will use a prelubricated wipe to clean the metal shavings instead of a grease gun, so she and Kimbrough don't have to share as much.

"You've got to remember, we are working with humans here and we are prone to human error," said flight director Ginger Kerrick. "So we do the best we can and we learn from our mistakes."

Once safely back inside the space station, the spacewalkers were to celebrate the 10th anniversary of the space station along with the five other Endeavour astronauts and the station's three crew mates.

The astronauts also wanted to run the first test on a newly delivered contraption that converts urine and sweat into drinkable water. Astronauts spent a good part of the day Wednesday hooking it up. The urine converter was delivered by Endeavour, along with other equipment, and will help turn the space station into a home for six crew members next year instead of the current three residents.