CAPE CANAVERAL, Florida (Reuters) – NASA has some advice for the elite Navy diver-turned-astronaut whose first spacewalk was cut short because of an air issue: Breathe easily. Endeavour astronaut Chris Cassidy and partner David Wolf were nearing the end of a spacewalk on Wednesday when carbon dioxide, a byproduct of breathing, started to build up in Cassidy's suit. The poisonous gas is chemically removed from the sealed spacesuit by a canister of lithium hydroxide.
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No heavy breathing, NASA tells spacewalkers
