From YahooNews: 

Bird droppings survive space launch

HOUSTON - NASA’s rocket scientists have a new appreciation for the out-of-this-world power of bird droppings. The orbiting space shuttle Discovery sported some whitish splotches on its black right wing edge that NASA officials said appeared to be bird droppings.
 
Shuttle lead flight director Tony Ceccacci said he saw the same splotches on the identical part of the shuttle about three weeks ago when Discovery was on the launch pad and laughed when pictures beamed back from space Wednesday showed they were still there.

That means these bird droppings withstood regular Florida thunderstorms, a mighty Fourth of July launch during which 300,000 gallons of water is sprayed at the shuttle’s main engines, and a burst upward through Earth’s atmosphere. During that launch Discovery went from zero to 17,500 mph in just under 9 minutes.

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