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Astronaut Andy Thomas helps place helmet on Soichi Noguchi as they prepare for Saturday's spacewalk.

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It is the two men's first walk into space.

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The walk gets under way with Steve Robinson moving along the shuttle's payload bay.

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A humble putty knife is used in the thermal protection repair test conducted.

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He spends part of his walk suspended from Discovery's robotic arm.

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There is time for snapshots, too, to record this latest step in the revival of the shuttle programme.