Discoverer 29, also known as Corona 9023, was an American optical reconnaissance satellite which was launched in 1961.

A Thor DM-21 Agena-B rocket was used, flying from Launch Complex 75-3-4 at the Vandenberg Air Force Base.

[2] Upon successfully reaching orbit, it was assigned the Harvard designation 1961 Psi 1.

[3] The satellite 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).

[2] Once its images had been returned, Discoverer 29 remained in orbit until it decayed on 9 September 1961.