Rocket scientists leave multi-billion dollar space shuttle with its fragile foam tank out in a hail storm.

Hailstones as big as golf balls put more than 7,000 dings into space shuttle Atlantis’ fuel tank Monday night and may delay the ship’s launch from March until June, NASA officials said Tuesday.

Wayne Hale, the shuttle’s program manager, said the storm did “the worst damage we’ve ever seen from hail” on the tank, which is covered in foam insulation with roughly the texture of a picnic cooler.

Not all of the thousands of dings in the foam will need to be fixed, said John Chapman, the tank manager. The deeper holes will be filled, and abrasions to the shuttle’s heat-shielding tiles will be repaired.

The damage will hurt NASA’s ability to work on the costly ($100 billion), useless space station that has a nearly one in five chance of being damaged so badly by space debris that the crew would have to evacuate.

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