The US military's X-37B space plane landed at NASA's Kennedy Space Center on Sunday, ending its record-breaking 718-day orbit with a sonic boom during its first landing in Florida. The US Air Force has two X-37B Orbital Test Vehicles, which it calls its newest and most advanced reentry spacecraft. At 29 feet long and with a 14-foot wingspan, the planes are about one-quarter of the size of NASA's now retired space shuttles and have a cargo bay about the size of a pick-up truck's. The first X-37 program started in 1999, and the X-37B first flew in April 2010,...