For those Europeans, there was still the option of turning it into a round trip. Granted, it was probably an expensive and arduous option, and required a ship i

For those Europeans, there was still the option of turning it into a round trip. Granted, it was probably an expensive and arduous option, and required a ship in port ready and willing to take you, but it was there. Right now, a one-way trip to Mars really is a one-way trip. That is, until we can put enough provisions up there to get a ship back out of that gravity well. And keep the occupants alive long enough to get back here.