The state-of-the-art NTP cycle is based on solid core Nuclear Engine for Rocket Vehicle Application (NERVA) class technology that is envisioned to provide a specific impulse (Isp) of 900 seconds doubling chemical rocket performance (450 seconds). Even with this impressive increase, the NTP NERVA designs still have issues providing adequate initial to final mass fractions for high DeltaV missions. Nuclear Electric Propulsion (NEP) can provide extremely high Isp ( over 10,000 seconds) but with only low thrust and limits on mass to power ratios. The need for an electric power source also adds the issue of heat rejection in space where thermal energy conversion is at best 30-40% under ideal conditions.