Mars Reconnaissance Orbiter launched in August 12, 2005 from Space Launch Complex 41 at Cape Canaveral Air Force Station. Launch took place during Earth's northern summer and during Mars' northern winter. The spacecraft used a Lockheed-Martin Atlas V-401 launch vehicle.
The launch period -- the time period in which the orbiter could launch -- lasted approximately three weeks (Aug. 10-30, 2005). Throughout the entire launch period, the mission had daily launch opportunities, known as "windows," of at least 30 minutes, the minimum needed for launch.
Many people think of lift-off as the launch, but there were actually several steps during the launch phase.
| Step One: | Countdown and systems checks |
| Step Two: | Lift Off through Atlas Stage 1 Booster, which accelerated the spacecraft to supersonic speeds of about 4,500 meters per second (10,000 miles per hour) |
| Step Three: | Booster Engine Cut Off for the Atlas Stage I Booster |
| Step Four: | Atlas Stage I Separation from the Centaur Stage II; Atlas fell back to Earth into the Atlantic Ocean |
| Step Five: | Main Engine Start of the Centaur Stage II |
| Step Six: | Centaur First Burn Phase, which lasted nine-and-a-half minutes, boosted the spacecraft into a "parking orbit" in which the spacecraft and Centaur coasted for about 33 minutes between the first and second Centaur burns |
| Step Seven: | Jettison of the Payload Fairing, which fell back to Earth into the Atlantic Ocean |
| Step Eight: | Main engine Cut Off for the Centaur First Burn |
| Step Nine: | Centaur Second Burn Phase, which lasted about 10 minutes, accelerated the spacecraft out of Earth orbit and set it on its way to Mars |
| Step Ten: | Main Engine Separation of the Centaur Stage II |
| Step Eleven: | Centaur collision avoidance maneuver, which ensured that the Centaur did not get in the way of the spacecraft or assume a flight path that would cause it to eventually impact Mars |
At this point, the launch phase ended, and the spacecraft continued in its cruise phase.
