DAVID JANES has an interesting picture that seems to show cracks in the Columbia left wing.
UPDATE: More, including some skepticism, here.
ANOTHER UPDATE: Still more skepticism here.
Meanwhile reader Woody Emanuel writes:
The supposed photo of a shuttle wing is totally bogus. Someone had fun conning a paper to publish it.
There is no possibility of viewing either the upper or lower wing surfaces from the shuttle unless on a spacewalk, and then only the upper part of the wing. You can’t see the wings from any window in the shuttle; the cargo bay doors are always open during flight blocking any view of the wings anyway.
There would be no “crack” anyway. Tiles don’t crack – they get damaged. And NASA saw no need for for a wood stove pipe extending from the wing.
Several readers had similar comments.