S133-E-006744 (26 Feb. 2011) --- On space shuttle Discovery's middeck, astronauts Eric Boe (left), STS-133 pilot; and Alvin Drew, mission specialist, work with lithium hydroxide canisters beneath the floor, performing the same house-keeping chore accomplished by many astronauts in the 30-year history of the Space Shuttle Program. Photo credit: NASA or National Aeronautics and Space Administration