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Catalog Data

Boeing Aerospace Company  Search this
aluminum, steel, Stainless Steel, Magnesium, glass, Paint, plastic, Acrylic (Plexiglas), Adhesive, Rubber (Silicone), Copper, brass, Phenolic Resin ,Composite, Epoxy, Synthetic Fabric
Shell - aluminum alloy
Solar cells - silicon
Overall: 16 3/4 × 16 1/2 in., 104.8cm (42.5 × 41.9cm, 41 1/4 in.)
Storage (Aluminum pallet and frame with fabric dust cover): 121.9 × 121.9 × 73.7cm, 57.2kg (48 × 48 × 29 in., 126lb.)
Country of Origin:
United States of America
Explorer XI, launched on April 27, 1961, by a Juno II rocket, was NASA's first fully dedicated gamma-ray satellite. The satellite was built under a contract overseen by the Marshall Space Flight Center who also supplied the supporting electronic equipment. It carried a gamma-ray telescope built at MIT by W. Kraushaar and G. Clark, and was designed to detect gamma radiation above 50 MeV. During a period of just over 23 days in orbit it detected 22 true gamma-ray events as well as 22,000 events due to charged cosmic rays. The artifact in the collection is one of two backup-up satellites.
NASA transferred the object to the Museum in 1975.
Credit Line:
Transferred from the National Aeronautics and Space Administration
Inventory Number:
Restrictions & Rights:
Usage conditions apply
See more items in:
National Air and Space Museum Collection
Data Source:
National Air and Space Museum