We can build a fuel station on Moon, which will make pellets of fuel, then shot them in direction of a spacecraft at Moon orbit. Spacecraft can collect them, th

We can build a fuel station on Moon, which will make pellets of fuel, then shot them in direction of a spacecraft at Moon orbit. Spacecraft can collect them, then fuel an ionic drive for constant acceleration for weeks. Moon has low gravity, no atmosphere, thus it makes it ideal for a railgun[0]. With a fuel station on Moon, it will be much cheaper to reach Mars, so it will be possible to build second fuel station at Fobos. With two fuel stations, it will be even cheaper to refuel a spacecraft for long-range missions. [0]: https://www.space.com/36442-could-moon-miners-use-railguns-to-launch-ore-into-space.html https://www.space.com/36442-could-moon-miners-use-railguns-t...