Discoverer 13 was an American optical reconnaissance satellite. The lastof five test flights of the Corona KH-1 spy satellite series. It was the first fully successfuly flight of the Discoverer series. It successfuly jetissoned its payload which was recovered in the Ocean by the Navy.
Thor-Agena was a series of orbital launch vehicles. The rockets used Thor first stages and Agena second stages. They are thus cousins of the more-famous Thor-Deltas, which founded the Delta rocket family.