The Thor-Delta also known as Delta DM-19 or just Delta was an early American expendable launch system used for 12 orbital launches in the early 1960s. A derivative of the Thor-Able it was a member of the Thor family of rockets and the first member of the Delta family.The first stage was a Thor missile in the DM-19 configuration. The second stage was the Delta which had been derived from the earlier Able stage. Given a list of categories: company, educational institution, artist, athlete, office holder, mean of transportation, building, natural place, village, animal, plant, album, film or written work, what category does the paragraph belong to?
A:
Mean Of Transportation