[1] It was an early electro-optical reconnaissance spacecraft, meaning that it transmitted images to receiving stations on Earth rather than returning them in a film capsule, and was to have been operated as part of the Samos programme.
Samos-E2 satellites were based on an Agena-B, and carried a camera with a focal length of 91 centimetres (36 in), and a resolution of 6 metres (20 ft).
An Atlas LV-3A Agena-B rocket was used, flying from Launch Complex 1-1 at the Point Arguello Naval Air Station.
[4] Samos 3 was to have operated in a Sun-synchronous low Earth orbit, at an altitude of 480 kilometres (300 mi) and with 83 degrees of inclination.
[2] Damage to SLC3 mainly affected electrical and plumbing components and repair work began almost immediately.