The average distance between Mars and Earth when it is closest to the Sun is 140 million miles. The two planets are farthest apart when they are both at their farthest from the sun, on opposite sides of the star. At this point, they can be 250 million miles apart. Now, it might be far, but it only takes around 6 or 7 months to get there. Maybe 5 if the shuttle is dependable. My point is that they will probably successfully land on Mars soon. But there will be a lot of problems during the far trip. An astronaut's body will realize when you are weightless in space, your bones are not needed, and they will become brittle, and bony. But I think they will succeed and overcome their problems with ease.