Please answer the following question: Pick one category for the following text. The options are - company, educational institution, artist, athlete, office holder, mean of transportation, building, natural place, village, animal, plant, album, film or written work. Thor-Agena - 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. The first attempted launch of a Thor-Agena was in January 1959. The first successful launch was on February 28 1959 launching Discoverer-1.
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Mean Of Transportation