SAN'A, Yemen: Call it the Trespasser mission. Three Yemeni men are suing NASA, claiming that the plucky Sojourner robot has been doing wheelies all over their front lawn. "We inherited the planet from our ancestors 3,000 years ago," explained planetary landlords Adam Ismail, Mustafa Khalil and Abdullah al-Umari in court documents. "Sojourner and Pathfinder. . . began exploring it without informing us or seeking our approval." Oh.