[CedarDave]

...hitting the wing...

Edge or bottom? NASA spokesman keeps refering to bottom of orbiter and how just the process of inspecting by spacewalk could cause more damage than any that might be present already. Seems like its the bottom of the wing they are concerned about. (Can't look at video while listening to briefing -- will crash my dial up connection).

[Budge]

It hit the leading edge, went under left wing, and came out sideways...sortta.

[MangyDingo]

It hit the bottom on the wing. The concern about sending the astronauts to look at it is due to several factors:

1) no handholds to the underside of the orbiter
2) no EVA thruster packs or MMU on board
3) the fragility of the tiles.

Sending an astronaut out to look at the underside of the orbiter would entail having him or her grip the hull of the orbiter in gloves that are bulky and aren't very good at gripping in that way.

The risk is that the astronaut will damage the surface of the orbiter, particularly the tiles on the leading edge of the wing, while dragging him or herself across the hull. There is the added danger that they could lose their grip along the way, tangle their umbilical, damage their spacesuit, etc. All this for a problem they can do nothing about, if it is critical. A bad suituation, but that's what they had.

Baron von Smash