From Wikipedia.com:

Ares I-X was the first test flight in the Ares I program, a launch system for human spaceflight currently under development by the United States space agency NASA. Ares I-X was successfully launched on October 28, 2009. The Ares I-X vehicle used in the test flight was similar in shape, weight, and size to the planned configuration of later Ares I vehicles, but had largely dissimilar internal hardware. Ares I vehicles are intended to launch Orion crew exploration vehicles. Along with the Ares V launch system and the Altair lunar lander, Ares I and Orion are part of NASA's Constellation Program, which is developing spacecraft for U.S. human spaceflight after the Space Shuttle fleet is expected to retire from service in 2010.