McArthur rides the shuttle's 50-ft robot arm during Sunday's spacewalk. Photo: NASA-JSC

Astronauts are not known for being overly emotional in space. But veteran shuttle flier William McArthur, making his first spacewalk today, clearly is a breed apart, barely able to control his excitement and enthusiasm as he marvels at the view from 240 miles up.

"Oh, sweet Jesus. Whoo whoo!" McArthur exclaimed as he floated out of the shuttle Discovery's airlock. "Outstanding."

A few moments later, he anchored his feet to a platform on the end of the shuttle's 50-foot-long robot arm and told arm operator Koichi Wakata, "OK Wakata-san. Let's go for a ride, buddy."

A few moments later, Discovery astronaut Michael Lopez-Alegria, perhaps fishing for a quote, asked McArthur "how's the ride?"

"Just, just wonderful,"McArthur said, momentarily at a loss for words.

"How do you like being a 500-pound spaceship?" Lopez-Alegria persisted.

"Ohhhh, this is too cool!" McArthur replied.

A more sedate McArthur pictured during spacewalk training. Photo: NASA-JSC

A few moments later, the West Point graudate was positioned high above Discovery's cargo bay, preparing to get to work making electrical connctions between the station and a new truss installed Saturday.

A veteran pilot, skydiver and shuttle astronaut, one might think McArthur would be hard to impress.

Apparently not, at least when it comes to walking in space.

"Being out on the end of the arm, not being able to see the shuttle, it is a strange feeling," he commented. "My toes are curling right up. Oh, good God! In a second, I might not be able to see any spaceship... ahhh... ahhh...

And then, matter of factly: "OK, this makes five years (of training) worthwhile."