Discoverer 33, also known as Corona 9026, was an American optical reconnaissance satellite which was lost in a launch failure in 1961.

A Thor DM-21 Agena-B rocket was used, flying from Launch Complex 75-3-5 at the Vandenberg Air Force Base.

[2] The launch ended in failure after the Agena suffered a hydraulics system malfunction that led to premature main engine shutdown.

It had a mass of 1,150 kilograms (2,540 lb),[4] and was equipped with a panoramic camera with a focal length of 61 centimetres (24 in), which had a maximum resolution of 7.6 metres (25 ft).

[5] It would have recorded images onto 70-millimeter (2.8 in) film, and returned this in a Satellite Recovery Vehicle at the end of its mission.