What will humans do that robots can not? Mining the moon for energy is a better proposition, I think. But never say never.
The Deferred Dreams Of Mars
people communicating with a large and sophisticated piece of equipment 150 million miles away as it began to carry out experiments that should enhance our understanding of whether the planet has or has ever had life ..... six astronauts could be sent on six-month flights to Mars and what they would do there for a year and a half before their six-month flights home ...... NASA could perpetually remain 20 years away from a manned Mars mission. ..... a Mars crew would see Earth shrink into just one of billions of twinkles in space ..... the astronauts would have to survive in a freezing, windswept world with unbreathable air and 38 percent of Earth's gravity ...... systems for feeding them, sheltering them ..... the benefits are mostly intangible ..... right now Curiosity is exploring these very questions, firing lasers at rocks to determine their composition and hunting for signs of microbial life ..... Because of such robotic missions, our knowledge of Mars has improved so much in the past 15 years that it's become harder to make the case for sending humans. ...... "For the cost of sending one human to Mars, you could send an entire flotilla of robots." ....... the space shuttle would fly 135 times from 1981 through 2011 .... Going into space for more than two years would subject the astronauts to an unprecedented degree of isolation and extended weightlessness; the longest stay in space so far has been 14 months. Potentially deadly cosmic rays, which are blocked by Earth's magnetic field and atmosphere, would hit the spacecraft in flight and threaten the astronauts on Mars. ..... the sky crane used to land Curiosity wouldn't work for landing humans, whose craft could weigh 30 times more ...... something entirely new: protect and feed humans on another planet over a long stretch ...... "closed loop" life-support systems in which water and air are recycled ....... possible to extract oxygen from the carbon dioxide that makes up 95 percent of the Martian air. ..... dehydrated food that astronauts inject with water on the space station can retain adequate nutrients for five years ...... Pressure-treating the food ..... make the habitat inflatable, so it could be packed tightly en route to Mars. ...... the bone loss, blurry vision, and other problems astronauts suffer when removed from Earth's gravity ...... compared with the money and effort that get spent in the service of "greed and our ancestral urge to beat the crap out of each other." ...... colonizing the moon, stimulating space tourism, and harvesting solar energy from geosynchronous Earth orbit