The world's largest airborne observatory plane, trailed by a fighter jet, startled residents and motorists in south Palo Alto and parts of Mountain View early this afternoon as it approached Moffett Field for a landing.
The Stratospheric Observatory for Infrared Astronomy (SOFIA) airborne observatory briefly visited NASA Ames Research Center, where it will someday be based after flight tests are completed.
Ames families and media representatives were invited to tour the plane during its brief non-public visit.
One witness said the big "747-type" plane flew in extremely low over south Palo Alto with the jet behind it, and people were stopping to stare up at them.
SOFIA is currently undergoing flight tests at NASA's Dryden Flight Research Center, Edwards, Calif.
SOFIA features a 98.4-inch diameter infrared telescope mounted in a modified Boeing 747SP aircraft. Flying at 41,000 to 45,000 feet, it will enable scientific observations that Earth-based telescopes cannot accomplish.
After flight tests are completed in about two years, SOFIA's science and mission operations will be managed by Ames, according to Michael Mewhinney of Ames public affairs office.