article_snippet.sent: D.C. Various forms of propulsion have been touted for a mission to Mars, including chemical, ion (electric) and nuclear.
article_snippet.sent: Shown is an illustration of a concept Mars Transfer Vehicle .
article_snippet.sent: Shown is a graph of the different types of propulsion for a mission to Mars
article_snippet.sent: CECE is a type of chemical propulsion, Nerva is nuclear propulsion, RIT-XT is ion (electric) propulsion and PEMT is Pure Electro-Magnetic Thrust .