Fusion Rockets.

Our current space program uses Liquid Rocket fuel to propel us into outer space. When dealing with interstellar travel, this form of transportation is impossible and hugely inefficient. one of the options i have talked about before was space sails using lasers and the sun to propel it. Another option is Fusion. We all know of the devastating effects of the Hydrogen bomb and the atom bomb, but recently scientist's are researching a way to turn this into a feasible way of transportation. Hydrogen is the preferred method of transportation since a ship could refuel in space since hydrogen is plentiful. this could reduce the amount of time to reach mars by 50%! fusion generated propulsion could generate up to 300 times the impulse of that of a current chemical rocket. The VASIMAR engine currently gives us a look at how the fusion engine creating plasma could work.
Forward cell - The propellant gas, typically hydrogen, is injected into this cell and ionized to create plasma.

Central cell - This cell acts as an amplifier to further heat the plasma with electromagnetic energy. Radio waves are used to add energy to the plasma, similar to how a microwave oven works.

Aft cell - A magnetic nozzle converts the energy of the plasma into velocity of the jet exhaust. The magnetic field that is used to expel the plasma also protects the spacecraft because it keeps the plasma from touching the shell of the spacecraft. Plasma would likely destroy any material it came in contact with. The temperature of the plasma exiting the nozzle is as hot as 180 million degrees Fahrenheit (100 million degrees Celsius). That's 25,000 times hotter than gases expelled from the space shuttle ( Article from Kevin Bosnor).
Going to mars would be great a great challenge for the earth to undertake, but a challenge i'm afraid that would take take great co-operation on all nations. An undertaking like this could do more then get to us to mars and advance our science, it could unite the nations under one common goal.