Physics of the Future: How Science Will Shape Human Destiny and Our Daily Lives by the Year 2100

comes close to earth.
    LANDING ON A MOON OF MARS
    Although the Augustine report did not support a manned mission to Mars, one intriguing possibility is to send astronauts to visit the moons of Mars, Phobos and Deimos. These moons are much smaller than earth’s moon and hence have a very low gravitational field. There are several advantages to landing on the moons of Mars, in addition to saving on cost.
     
    1. First, these moons could be used as space stations. They would provide a cheap way of analyzing the planet from space without visiting it.
    2. Second, they could eventually provide an easy way to access Mars. Phobos is less than 6,000 miles from the center of Mars, so a quick journey to the Red Planet can be made within a matter of hours.
    3. These moons would probably have caves that could be used for a permanent manned base to protect against meteors and radiation. Phobos, in particular, has the huge Stickney crater on its side, indicating that the moon was probably hit by a huge meteor and almost blown apart. However, gravity slowly brought back the pieces and reassembled the moon. There are probably plenty of caves and gaps left over from this ancient collision.
    BACK TO THE MOON
    The Augustine report also mentioned a Moon First program, where we would go back to the moon, but only if more funding were available—at least $30 billion over ten years. Since that is unlikely, the moon program, in effect, is canceled, at least for the coming years.
    The canceled moon mission was called the Constellation Program, which consisted of several major components. First was the booster rocket, the Ares, the first major U.S. booster rocket since the old Saturn rocket was mothballed back in the 1970s. On top of the Ares sat the Orion module, which could carry six astronauts to the space station or four astronauts to the moon. Then there was the Altair lander, which was supposed to actually land on the moon.
    The old space shuttle, where the shuttle rocket was placed on the side of the booster rocket, had a number of design flaws, including the tendencyof the rocket to shed pieces of foam. This had disastrous consequences for the Space Shuttle
Columbia,
which broke up on reentry in 2003, killing seven brave astronauts, because a piece of foam from the booster rocket hit the shuttle and made a hole in its wing during takeoff. Upon reentry, hot gases penetrated the hull of the
Columbia,
killing everyone inside and causing the ship to break up. In the Constellation, with the crew module placed directly on top of the booster rocket, this would no longer be a problem.
    The Constellation program had been called “an Apollo program on steroids” by the press, since it looked very much like the moon rocket program of the 1970s. The Ares I booster was to be 325 feet tall, comparable to the 363-foot Saturn V rocket. It was supposed to carry the Orion module into space, replacing the old space shuttle. But for very heavy lifting, NASA was to use the Ares V rocket, which was 381 feet tall and capable of taking 207 tons of payload into space. The Ares V rocket would have been the backbone of any mission to the moon or Mars. (Although the Ares has been canceled, there is talk of perhaps salvaging some of these components for future missions.)
    PERMANENT MOON BASE
    Although the Constellation Program was canceled by President Obama, he left open several options. The Orion module, which was to have taken our astronauts back to the moon, is now being considered as an escape pod for the International Space Station. At some point in the future, when the economy recovers, another administration may want to set its sights on the moon again, including a moon base.
    The task of establishing a permanent presence on the moon faces many obstacles. The first is micrometeorites. Because the moon is airless, rocks from space frequently hit it. We can see this by viewing its surface, pock-marked by meteorite collisions, some dating back billions of years.
    I got a personal look at this danger when I was a graduate student at the University of California at Berkeley. Moon rocks brought back from space in the early 1970s were creating a sensation in the scientific community. I was invited into a laboratory that was analyzing moon rock under a microscope. The rock I saw looked ordinary, since moon rock very closely resembles earth rock, but under the microscope I got quite a shock. I sawtiny meteor craters in the rock, and inside them I saw even