NASA’s chief, Charles Bolden, says these projects ensure the United States will be the world leader in exploring Mars. He wants the space agency to take major steps in preparation for sending astronauts to the planet in 20 years.

Curiosity has been studying the atmosphere, making maps of wind and radiation patterns, and measuring changes in air pressure on Mars.

Ashwin Vasavada is the deputy project scientist for the Curiosity mission. He says the mission is mainly concerned about ancient Mars. But he says researchers also want to learn about the planet’s current environment.

“And it’s a pretty dynamic environment. If you were standing next to Curiosity, you’d realize you’re on a planet with an atmosphere -- an atmosphere that is thick enough that when the sun heats the ground every day, gusty winds rush up and down the slopes of Gale Crater and Mount Sharp and spawn whirlwinds that sweep across the landscape. But the atmosphere isn’t thick enough to shield you from the harsh ultraviolet light and the natural high-energy radiation coming in from space.”

Learning about that radiation is important. So scientists placed a Radiation Assessment Detector, or RAD, on Curiosity. Don Hassler is watching the radiation levels.

“The radiation is a life-limiting factor to habitability, so we need to understand what the radiation is doing if we want to understand the prospects for both current, present, and past habitability, but we also need to understand the radiation environment. When we send astronauts to Mars in the future, we need to be able to fully-understand what the radiation is doing so that we can help plan a safe mission for those astronauts.”