Whistle While You Work? Not in Space Pressurized spacesuits make it impossible for astronauts to whistle.

Feb. 22, 2007  -- Snow White's seven dwarfs could do it. So could Andy Griffith. Lauren Bacall told Humphrey Bogart, "You just put your lips together and blow."

They could all whistle, but astronauts on spacewalks will never, ever be able to whistle while they work.

When you're on a spacewalk, says astronaut Jim Reilly, your voice changes. "You can't whistle, so you'll never hear anyone whistling on their way to work on a spacewalk. You'll hear them humming, but you won't hear them whistling."

Reilly will be one of four astronauts performing EVAs -- short for Extra Vehicular Activity -- on STS-117, next month's scheduled shuttle mission to the International Space Station.

Former astronaut Dan Barry has seven hours of spacewalking time to his credit. He tried whistling during his spacewalk on STS-96 in May 1999.

"It wasn't something I hadn't planned -- I thought of it on the fly. It turned out that it didn't work.," he said.

Barry called down to Mission Control and said, "Houston, EV2. The science types might like to know that it is not possible to whistle during an EVA."

Story Musgrave, a veteran of six flights, was the capsule communicator that day, and his droll response to Barry -- "We know, Dan" -- cracked Barry up, allowing Barry to discover that while he couldn't whistle, he could certainly laugh.

A Simple Matter of Air Pressure

So why can't people whistle while spacewalking? Barry said there is a simple explanation.

"You can't whistle because the air pressure in the suit is only 4.3 [pounds per square inch], and normal atmospheric pressure is 14.7 psi, so there are not enough air molecules blowing by your lips to make a sound," he said.

What would Barry have whistled if he could have? "'Whistle While You Work,'" he said.

Former astronaut Tom Jones says he wasn't much of a whistler, but he found that while he was out on his spacewalks there were some songs he just couldn't get out of his head: the theme to the TV show "Leave It to Beaver" and Carly Simon's "Let the River Run."

Veteran spacewalker Robert Curbeam didn't know he couldn't whistle and says he never tried.

He was busy during the last mission installing trusses and watching the world whip by at 5 miles a second while getting a sticky solar array to retract. He says that if he had tried whistling, it would likely have been "The Girl From Ipanema," because he catches himself whistling it on Earth.

Jeff Hoffman, a retired astronaut with three spacewalks (including a mission to repair the Hubble telescope) has traveled 21.5 million miles in space. He said the technicians who trained him on spacewalks had told him that he wouldn't be able to whistle, but he says he tried anyway.

"I couldn't get one note out," he said.