What is a launch vehicle?
A launch vehicle provides the velocity needed by a spacecraft to escape Earth's gravity and set it on its course for Mars.
Launch vehicle for this mission
Designed to launch in 2020, the Mars 2020 mission would take advantage of a favorable launch opportunity when Earth and Mars are in advantageous positions in their orbits for a Mars landing. That means that it would take less power to get to Mars relative to other times when Earth and Mars are in different positions in their orbits around the sun.
When mission planners are considering different launch vehicles, what they take into consideration is how much mass each launch vehicle can lift into space. The Mars 2020 rover mission would use heritage technologies based on the Mars Science Laboratory mission, which was designed to allow large-mass payloads to reach the surface of Mars safely.
Launch vehicle selection criteria would encompass the final architecture for this mission, including total mass. For a sense of overall potential mass, the Mars Science Laboratory mission had a total launch mass, including the intermediate class rocket that lifted it away from Earth, of about 531,000 kilograms (1.17 million pounds).
The integrated 2020 flight system would also likely be launched on an Intermediate-class launch vehicle.