Advanced Orbiting Solar Observatory


Display Status:

This object is on display in the Space Science exhibition at the Steven F. Udvar-Hazy Center in Chantilly, VA.

Collection Item Summary:

This is the full-scale engineering flight model of the Advanced Orbiting Solar Observatory (AOSO) representing its most complete configuration. This satellite was designed as a scaled-up counterpart to the Orbiting Solar Observatory series in the early 1960s. It was conceived as a free-flying, robotic, polar-orbiting satellite system capable of continuously monitoring the sun and near solar environment using an array of detectors and electronic imaging devices covering a broad frequency band from the x-ray to the visual range. Many of the scientific instruments planned for AOSO eventually were developed for the Skylab Apollo Telescope Mount, which flew in 1973.

The AOSO program was canceled in 1965, and this object was transferred to NASM by NASA in 1969. The historical question remains: why was AOSO cancelled? One conjecture: in the mid-1960s electronic imaging and recording was still not reliable enough to handle very high resolution images of spectra and spatial objects. Film recording required either on-board scanning and telemetry, or physical return. The latter would be possible if the satellite was periodically attended by astronauts. This requjirement lent itself to plans for the post-Apollo Skylab program. Accordingly, the array of telescopes, as reconfigured for Skylab, came to be known as the Apollo Telescope Mount.

Collection Item Long Description:

Data Source

National Air and Space Museum

Restrictions & Rights

Do not reproduce without permission from the Smithsonian Institution, National Air and Space Museum

Credit Line

Transferred from the National Aeronautics and Space Administration


Aluminum sheet and bar stock


Overall: 4ft 12in. x 10ft 6in., 1075lb. (152.4 x 320cm, 487.6kg)

Country of Origin

United States of America



Inventory Number