As rovers and orbiters continue to scour Mars for more signs of water and the potential for extraterrestrial life, space scientists and enthusiasts are champing at the bit to put humans on the red planet. “There’s no question we’ll ultimately go there. It’s a matter of when, not if,” said Lynn Rothschild, an astrobiologist at the NASA Ames Research Center in Moffett Field, California. Robert Zubrin is the president of the Mars Society, a Colorado-based organization that promotes human exploration and settlement of the red planet. He said the technology exists to put humans on Mars within a decade. “We are much closer to being able to send humans to Mars today than we were to being able to send men to the moon in 1961, when [United States President John F. Kennedy] started the Apollo program,” Zubrin said.