Using in-situ propellant has been a central pillar of the plan to explore much of the solar system. The logic is simple – the less mass (especially in the form of propellant) we have to take out of Earth’s gravity well, the less…

Using in-situ propellant has been a central pillar of the plan to explore much of the solar system. The logic is simple – the less mass (especially in the form of propellant) we have to take out of Earth’s gravity well, the less…