What is the Crew Exploration Vehicle (CEV)?
The CEV is America’s new spacecraft for human space exploration. It will be able to ferry crews of three astronauts (plus additional cargo) to and from the International Space Station, but has the capability to carry as many as six crew members. It will take four crewmembers to lunar orbit, and even return up to six crewmembers to Earth on the final leg of a human Mars mission.
Why are we going back to the moon?
Returning to the moon is an important component of the President's Vision for Space Exploration.
The moon also provides opportunities to develop technologies and techniques needed for opening the space frontier. It allows us to learn how to survive long term stays on other worlds while only three days travel time from Earth. This will build confidence that we can stay on the surface of another planet for longer periods of time and ultimately venture to Mars. And of course, it provides opportunities to conduct fundamental science such as astrobiology and geology.
What are we going to do on the moon?
We will learn more about the art of exploration on the moon. Since the last Apollo mission there, robotic missions have raised intriguing new science questions, such as the character of the water ice in the permanently shadowed craters near the lunar poles. So there is new fundamental science to be performed. More so, we will be learning to live on the new frontier - we'll be learning how to "live off the land" by making oxygen and rocket propellants from the local materials, and we'll be testing new technologies and operations that will allow us to travel on to Mars and then beyond.
Why don't we fly the shuttle to the moon?
The space shuttle is not designed for use beyond low-Earth orbit. Wings are not necessary. There are several issues that prevent the use of the space shuttle for lunar exploration. To escape the Earth's gravity, any spacecraft must attain a speed of more than 17,500 mph. The shuttle is designed for re-entry from an Earth orbital speed of 17,500 mph, not the 25,000 mph speed of a moon mission. Entering the Earth's atmosphere at this high speed would destroy the shuttle because it would exceed the wing and fuselage load limits. Currently, there is no thermal protection system that would protect the wings from such a high heat load.
