If humans one day settle Mars, they will need tools and parts to build structures on the planet. Carrying heavy, bulky supplies 34 million miles from Earth would be impractical. A better plan, says Zane Mebruer, a recent graduate of the University of Arkansas (U of A), would be 3D printing items on the Red Planet. His new research, completed while he was an honors undergraduate in mechanical engineering at the U of A, suggests it may be possible.