New and Improved Antimatter Spaceship for Mars Missions and the x-43A & x-43B

A little dose of reality today...

Most self-respecting starships in science fiction stories use antimatter as fuel for a good reason – it’s the most potent fuel known. While tons of chemical fuel are needed to propel a human mission to Mars, just tens of milligrams of antimatter will do (a milligram is about one-thousandth the weight of a piece of the original M&M candy).

However, in reality this power comes with a price. Some antimatter reactions produce blasts of high energy gamma rays. Gamma rays are like X-rays on steroids. They penetrate matter and break apart molecules in cells, so they are not healthy to be around. High-energy gamma rays can also make the engines radioactive by fragmenting atoms of the engine material. Read the rest of the article :
http://www.nasa.gov/centers/goddard/news/topstory/2006/antimatter_spaceship.html

Source : http://conceptships.blogspot.com/2007/12/new-and-improved-antimatter-spaceship.html