Northrop Grumman currently leads the development of the B-21 Raider, a long-range, stealth strategic bomber that can drop conventional and nuclear weapons; it will replace Northrop's own B-2 Spirit, the world's only known stealth bomber. Among its other current projects are development and production of the James Webb Space Telescope, an orbiting observatory slated for launch in 2021; and production of the solid rocket boosters for NASA's Space Launch System program. It was the sole bidder on the Air Force's Ground Based Strategic Deterrent program, which aims to develop and build a new intercontinental ballistic missile.