Bimodal Nuclear Thermal Rockets conduct nuclear fission reactions similar to those safely employed at nuclear power plants including submarines. The energy is used to heat the liquid hydrogen propellant. Advocates of nuclear powered spacecraft point out that at the time of launch, there is almost no radiation released from the nuclear reactors. The nuclear-powered rockets are not used to lift off the Earth. Nuclear thermal rockets can provide great performance advantages compared to chemical propulsion systems. Nuclear power sources could also be used to provide the spacecraft with electrical power for operations and scientific instrumentation.
NASA/Pat Rawlings (SAIC)
2009
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