The Kuiper Airborne Observatory

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The Kuiper Airborne Observatory (KAO) is a C-141 Starlifter aircraft that has been modified to carry a 1 meter diameter infrared telescope into the stratosphere. Far infrared is extremely useful in seeing through many of our galaxy's dust clouds but it is almost totally absorbed by water vapor in our atmosphere. Flying at 41,000 ft (12.5 km) is above the troposphere and 98% of all water vapor. The electronics and especially the charge-coupled devices (CCD) that make up the detector for the IR telescope are strongly affected by cosmic rays. This created a strong interest among the KAO researchers in our auxiliary CCRT experiment. Steve Kliewer and Jean Roberts (center and right) are high school teachers in Fresno, CA. Steve Cox is observing for the Rotary Club, which funded our trip.

07 CCRT installed aboard the KAO

An out of the way, safe and secure location was found for the equipment. Because of safety issues, power is shut down and no measurements were allowed as we rapidly ascended and later descended

08 KAO Mission Operations

During the mission we flew all night long from Honolulu due west for 4 hours and then returned. The researchers aboard, spent the night acquiring each planned object and then painstakingly and repetitively measuring the IR intensity at several wavelengths compared to the background. The liquid helium-cooled, CCD detectors were pushed to their detection limits. A complex protocol of "chopping the signal" and "nodding the telescope" was used in order to get the maximum accuracy possible. However, cosmic rays randomly cause saturation of these CCD detectors. This requires a much greater number of measurements so that the effects of cosmic rays may be statistically eliminated.