Standing in the way of a manned mission to Mars is the journey time and funding. The radical Vasimr engine could reduce the journey from 9months to 39days and Nasa's recent course change might have freed up the money to help pay for it.
One of the biggest obstacles facing any manned Mars mission, aside from the financial one, is the sheer length of time it takes to get there. Using conventional rockets, the best journey time we can hope to achieve is six to seven months, during which time your Martian pioneers would lose a bit of their edge. Without gravity, the cardiovascular system weakens and the vertebrae will pull apart. Unused muscles will atrophy and bones will lose so much calcium they become fragile and prone to fracture. That’s not to mention the psychological effects of months of incarceration and isolation. In short, by the time your hero touches down, he will be more Supergran than Superman.
As power sources go, nuclear fusion is the oldest and most efficient, and can boast a track record that is second to none. It has helped nurture life on Earth and neither we, the food we eat or air we breathe could exist without it. Nuclear fusion, not to be confused with nuclear fission (used in present nuclear power stations), is the process by which the Sun, and other stars, transforms hydrogen into helium to release the colossal amount of energy that keeps them burning away.
Nuclear fusion – How HiPER will use lasers to create a 'star on Earth' to power the planet