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.