Getting to Mars and back to the moon could be much easier if, instead of doing it as a single mission, we create "supply lines" between Earth and our destination. These supply lines could be composed of mostly floating biospheres which, harness the sun's energy to create many floating Eco-systems arranged in a long line reaching the moon and then Mars. All along these supply lines people live and work. Once a supply line was established between Earth and the moon, for instance, getting to the moon would simply be a process of sending people from Earth to the closest point of the supply line and having them follow the line, (skip from biosphere to biosphere) all the way to the moon. If something happened along the way, there would be no need to panic since the supply line would be composed of thousands of redundant and always nearby biospheres which always available space transports can dock and ferry people to and from along the line. And, of course, the same thing could be done in the example of Mars, with perhaps some alteration to account for the distance from the sun. Since the supply lines themselves would essentially function as planets, in a sense, themselves, there would also be no rush while transiting to the moon or Mars. You could take your time as you transited the supply line since life sustaining resources and safe harbor would always be available at any point along the supply line. Moreover, this plan would require many people in space to keep in working operation and so spur a space economy as well as ring in serious colonization of space. Sending one mission here or there is not going to change much because the next mission would be just as risky without a supply line. But the construction of supply lines actually gives us a real project in space with an eventual real payoff. And it would payoff in multiple areas. 1.) it would firmly establish permanent human colonies in space. 2.) The influx of humans in space would create a space economy. 3.) it would make transiting to the moon and Mars infinitely safer. 4.) once in place, the biosphere supply lines can get resources from two sources, the resources they generate themselves and any resources we care to send up from Earth to them. 5.) if resources are being created in space, that means an economy would develop going from space to Earth because people would want to buy things that said Made in Space on them. And the great thing about it is, it's a safe way to get to Mars. As the construction of such a line would begin at the closest point to Earth in space, we could simply build our way to Mars without ever leaving behind a direct tether to Earth and its life sustaining resources. In other words, we kill two birds with one stone: on the way to Mars, we get a supply line with a permanent human colony in space and all that entails. That means going to and coming back from Mars or the moon is as easy as jumping from one river stone to another, instead of trying to make it all in one great and risky leap. So the first step in building these supply lines is to get serious about farming in space. We need to build floating mega farms in space that can supply food to space colonists. Plants, of course, can generate oxygen that can be used to sustain the biosphere Eco-system, as well. We will need to create whole Eco-systems and habitats in space.