Federal scientists are looking for evidence that a bolt of electricity in the upper atmosphere might have doomed the space shuttle Columbia as it streaked over California. Investigators are combing records from a network of ultra-sensitive instruments that might have detected a faint thunderclap in the upper atmosphere at the same time a photograph taken by a San Francisco astronomer appears to show a purplish bolt of lightning striking the shuttle. Los Alamos National Laboratories physicist Mark Stanley said that we've seen very strong ionization in sprites" indicating that there were enough air molecules ionized to cause heating and an accompanying pulse -- a celestial thunderclap, as it were. NASA administrators confirmed Thursday that the photograph ... is being evaluated by Columbia crash investigators. The astronomer, who has asked that his name not be used, has declined to release the digital image to the media. [A] family of "transient" electrical effects occup[ies] this part of the sky, including sprites, which leap from the ionosphere to the tops of thunderheads. Ironically, an experiment of Israeli astronaut Ilan Ramon, aboard the doomed Columbia, was among the last fully funded work conducted on sprites. Scientists have observed interaction between a blue jet and a meteor. And in December 1999, Los Alamos National Laboratories researcher David Suszcynsky and colleagues, including Lyons, published an account of a meteor that apparently triggered a sprite.