- NASA did not attempt to examine Columbia's left wing with high-powered telescopes on the ground, 180 miles below, or with spy satellites. The last time NASA tried that, to check Discovery's drag-chute compartment during John Glenn's shuttle flight in 1998, the pictures were of little use, Dittemore said. Besides, he said, "there was zero we could have done about it."
- Similarly, NASA did not ask the crew of international space station to use its cameras to examine the wing when the two ships passed within a few hundred miles of each other several times over the past two weeks.
- NASA did not consider a spacewalk by the crew to inspect the left wing. The astronauts are not trained or equipped to repair tile damage anywhere on the shuttle, least of all on a relatively inaccessible area like the underside of a wing, Dittemore said.
Could NASA have sent another shuttle to rescue Columbia's five men and two women?
In theory, yes.
http://ap.tbo.com/ap/breaking/MGAV4BIIPBD.html
Actually, Rainmaker, NASA couldn't have sent another shuttle to rescue Columbia. Prep time to launch is at least 6 weeks. In an emergency, they could perhaps cut that in half, but still well short of any envelope needed to rescue the crew.