HOUSTON--Astronauts aboard the International Space Station and shuttle Discovery slept in protected areas of their respective spacecraft overnight to avoid the effects of a radiation storm kicked up by a massive solar flare, NASA officials said Wednesday.

NASA commentator John Ira Petty said that at no time were Discovery's STS-116 shuttle astronauts and the station's Expedition 14 crew at risk, and that the decision to sleep in sheltered areas of their spacecraft was just a precaution should solar storm activity increase overnight.

"That move was made to avoid having to wake the crew during their sleep period," Petty said. "It was never a danger to the crew."

Petty added that the effects of the crew hampered some communications during a Tuesday spacewalk, but the solar storm causing it appeared to be on the decline.

"Shortly after the crew went to bed, solar activity appeared to be subsiding," Petty said.

Protected areas of NASA shuttle's and the ISS include the orbiter's middeck and the aft ends of the space station's U.S. Destiny laboratory and Russian-built Zvezda service module.

Concern surrounded a massive X-3 solar flare that erupted late Tuesday from a large sunspot moving across the Sun. The event prevented some Sun-watching satellites from performing their duties and is rather rare, considering the Sun is currently at a low point in its 11-year cycle of solar activity.

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