Not since Newton's apple has there been a physics phenomenon as deliciously appealing to the masses as Frank Close's Cosmic Onion. Widely embraced by scientists and laypersons alike, the book quickly became an international bestseller, has been translated into seven languages, and propelled the author to become a recognized popular science celebrity around the world. Much has changed since the original publication in 1983, and The New Cosmic Onion was extensively revised and updated to reflect our new view of the universe. Keeping the best contents from the previous work, this new edition includes extensive new material explaining the scientific challenges at the start of this century.