In the 1960s, fusion propulsion concepts emerged from nuclear propulsion research, offering the potential for interstellar journeys within a human lifetime. These systems fell into two categories: Magnetic Confinement Fusion (MCF), which heats propellant to over 100 million °C, and Inertial Confinement Fusion (ICF), which uses lasers to compress fuel pellets. Theoretical specific impulse ranged from 10,000 to 1,000,000 seconds, enabling exhaust velocities up to 9,806,650 m/s. At such speeds, a fusion-powered spacecraft could reach Proxima Centauri in about 130 years, though some concepts promised faster transits.