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 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. This mission uses 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 would depend on 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 rockets that lifted it away from Earth, of about 531,000 kilograms (1.17 million pounds).