This is the original flown 12-inch infrared telescope that was mounted in the cabin of a Learjet aircraft. It was built by Dr. Frank Low and his students at Rice University using a range of bolometric detectors at its compound focus. The telescope flew several times in the late 1960s and early 1970s aboard a modified Learjet managed by NASA's Ames Research Center. Scientists used it to detect and measure thermal radiation from Jupiter and to study protostars and the centers of active galaxies. The telescope served as the prototype for infrared telescopes used on the much larger Kuiper Airborne Observatory, also based at Ames. It was transferred to a member of the Kuiper team, Dr. D. A. Harper of the University of Chicago's Yerkes Observatory, who donated it to the Smithsonian in 1983. The National Air and Space Museum displayed the telescope, mounted in a mockup section of a Learjet cabin, in its Stars gallery.