A 1.67 pound chunk of foam shed from Columbias external tank hit the shuttles left wing and caused a hole that allowed the searing gases of re-entry to melt the wing from the inside out. The shuttle disintegrated over Texas as it returned to Florida. All seven astronauts died.
NASA spent hundreds of millions of dollars over 2{ years redesigning the external tank, but said last week it did not solve the problem and more work is needed.
Bill Gerstenmaier, the stations program manager, said Discovery will leave the station in much better shape than when it arrived. Water will be left behind, as well as laptops, wash cloths, a printer, dry wipes, floppy disks, food and nitrogen.
We are going to be in very good shape through the end of the year, Gerstenmaier said.
Shuttles are needed for the supplying and continued construction of the station.
When NASAs shuttles were grounded in 2003, the agency began relying on Russian vehicles to deliver supplies to the station. However, the Russian cargo ship Progress cannot haul the weighty items the shuttle can. The next delivery by Progress is scheduled for September.
Gerstenmaier said station managers prepared for a scenario in which there would be no shuttle flights this year. Despite that, he said the grounding of future shuttle missions opens the station to risk.
We are still susceptible to some large failure of some component that can only be delivered by the shuttle that we dont have a like spare on station, he said.
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