Owl - Credit: USAF. 24,662 bytes. 280 x 315 pixels.

Originally to be part of the Explorer series, but instead orbited under the auspices of the US Army, Owl was designed to investigate a variety of low and high latitude phenomena and to make particularly powerful studies of auroral phenomena. Rice University built 2 spacecraft, scheduled for late 1968 launch by Scout boosters. The satellites were put into similar but not identical orbits at a high inclination with nominal altitudes of 930 and 1100 km and with coincident but antiparallel lines of nodes. The two flight units (Rice also built a flight-worthy spare and prototypes of selected subsystems) were identical except that a large permanent magnet was in opposite directions. Each satellite had a flight mass of about 70 kg; cylindrical, it had a height of 0.84 m and a diameter of about 0.76 m. Power was obtained by 8.000 solar cells distributed on all sides.

Total Mass: 60 kg.

Named as part of Transit satellite series. Actually different spacecraft for auroral and ionospheric research and not part of the navigation system.

Named as part of Transit satellite series. Actually different spacecraft for auroral and ionospheric research and not part of the navigation system.

• 405 - Aerospace Yearbook, 1966, .