It is one thing to travel to the moon, quite another to travel to one of the other planets in the solar system, even the closest and least hostile, Mars. The difficulties start when lifting off from the earths surface, a massive rocket like SpaceX Starship, with an all-up weight of the order of five thousand tones, on a good day can only lift two hundred tonnes into low earth orbit. Two hundred tonnes is a very small spaceship, even if you fit several units together in space that is still a lot of effort for a small ship. You can engineer a spaceship to be reliable, some of our oldest satellites are still drifting into inter stellar space and on occasions respond to us when challenged. The problem is the human factor, it is the frailties of man which prevented the early attempts to go to and return from Mars, not even getting halfway which drove Daniel Winstanley to look to another way.
Discarding the rocket as an area of technology that had topped out and was not going to meet his needs, he pursued building a space elevator based on using a thread of carbon nano tube forty thousand kilometres long, the thinnest of threads was used to make the connection between earth and the counter weight far above geostationary orbit, other threads were pulled up that first connection, and as each tether was strung the structure became stronger and more capable, finally, strong enough to support stations and the construction of a space ship which was to the early Martian vehicles as the Queen Mary was to the Ryde ferry.
Man went to Masr, not in numbers you could count on the fingers of one hand, but in the hundreds. Still the human factor was a threat to the success of the mission, for there were those religious fundamentalists who deemed it wrong to leave the surface of the earth determined that the PEGASUS would fail. And while the scientists and crew of the interplanetary ship worked to explore the Red Planet, a search started on earth to find who amongst them was planning their failure.