SOFIA, NASA’s 747-mounted flying telescope, has passed a crucial test, as there “were no problems with aircraft handling, vibrations or acoustic resonance.” What purpose does this flying telescope serve? Well, it “will be a world-class observatory for research astronomy.” Videos after the break.

The plane will fly in a long arc across the sky between 41,000 and 45,000 feet, above 99 percent of infrared-blocking atmospheric water vapor. The autopilot and telescope computers will communicate so astronomers can track a single object throughout the flight.