BBC NEWS | Science/Nature | Nasa: 'Ice impact risk acceptable'

"Ice striking the shuttle's heat shield remains a possibility, but the risk is low enough to safely resume flights, top officials with the US space agency have decided.

'At the end of the day, the recommendation... was that we're in an acceptable risk posture and that we proceed on with the launch,' shuttle programme manager Bill Parsons said." (more ice ice baby at link, yo)
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