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A crewed mission would need to contend with long travel times—years rather than days—exposing astronauts to numerous dangers, including prolonged microgravity, radiation, and psychological stresses. Rockets used today require vast fuel supplies, increasing ship weight and complicating launch logistics. Alternatives such as radioisotope thermoelectric generators (RTGs) could supply power but entail radiation hazards that must be managed carefully.
Challenges of Interplanetary Human Travel
Long-duration space missions pose significant challenges beyond propulsion. Critical considerations include: