PACKING FOR MARS

The Curious Science of Life in the Void

By Mary Roach

Norton. 334 pp. $25.95

Between the belly laughs, you learn a lot of surprising stuff in Mary Roach's "Packing for Mars" -- the kind of delightfully useless facts that will amaze your friends at parties. Facts like these:

-- During a week in space, with no gravity tugging at their spines, astronauts grow two inches taller.

-- Researchers requiring a vomit-like substance for scientific studies use Progresso vegetable soup.

-- A V-2 rocket launched in New Mexico in 1947 zoomed wildly off course and crashed three miles from downtown Juarez, Mexico.

-- In 1965, astronaut John Young smuggled a corned-beef sandwich aboard the Gemini III capsule and into space.

-- During the 1969 Apollo 10 mission, astronaut Thomas Stafford noticed an unpleasantly post-digestive object floating through the weightless cabin, and the official mission transcript recorded this conversation:

"Who did it?" Stafford asked.

"I didn't do it," Young said. "It ain't one of mine."