The looming threat of Hurricane Dean will force NASA's shuttle Endeavour to land Tuesday, one day earlier than planned, mission managers said Friday.

Meanwhile, spacewalkers Clayton Anderson and Dave Williams paused in their work outside the International Space Station to gaze at the monster storm.

"Hoo man, you can't miss that," Williams said from his perch outside the ISS. "Holy smokes, that's impressive."

"Scary," Anderson said of the storm. "It's only impressive when it's not coming to you."

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