There are many people, companies, and organizations working on many different routes for manned spaceflight right now (including me). SpaceX is farthest ahead right now, with the first test of their heavy launch vehicle (flying from the old Shuttle pad) scheduled for next year.

With luck, SpaceX and Boeing will both be flying astronauts to the Space Station in their respective space capsules sometime in 2017.

Next Orion flight will be in 2018, and the first manned flight will be around 2021. They still haven’t quite figured out the propulsion system for their launch vehicle.

I would prefer to see various components being developed simultaneously, such as heavy and light lift capability, emergency escape-from-orbit vehicle, a quick-prep resupply ship, space assembly and port orbit facilities, (as opposed to easily accessible orbital work stations), a deep space manned probe for long-term planetary exploration and a carbine version of the same for shorter near-earth missions (this is what Orion looks like to me). Other components might include a space tug (generic deep space propulsion module)or an expendable habitat module. Regardless of the final mission requirements, we’ll have a tool box filled with solutions.

In this way, we would have a variety of vehicles and support facilities (as well as communications networks)in place which could be quickly assembled for an unexpected mission of opportunity. And if for any reason, if any one component failed, or would be replaced with something better, the rest of the modules would still be usable. We would have a smorgasbord set of options in place, instead of an a la carte solution to just one problem.

I would think this sort of arrangement would be more flexible. Individual components could be farmed out to different companies (or countries) for development, and if there were delays or problems with some there would still be some alternate missions possible with existing hardware until that particular component was on line. Likewise, an unexpected technological breakthrough in any one area (such as a quantum leap forward in propulsion technology) would not make the whole system suddenly obsolete.

This approach would have the additional advantage of distributing the space effort to many separate companies and countries, and it would be less vulnerable to an economic or political failure in any one authority. Some catastrophe like a war or depression might make the space infrastructure less capable overall, but it would also make it less likely to seize up altogether. This would make its long turn survival more secure.

Granted, it might make better sense for one massive super-agency to plan this all out and manage it carefully, but massive super agencies, as we have seen, have a tendency to be unstable and prone to ossification–or to just lose their funding and public support.

There will be other modules, including one or more for habitation. And NASA, sadly, is soliciting other countries for assistance with this project. Much like ISS.

(Given the size of the US budget, the priorities of the US budget, it’s a crying shame NASA doesn’t get more.)

And it’s not surprising that the re-entry module looks like Apollo. Given the mission and the parameters there may only one good solution. Soyuz looks to be about the same, too. Until newer materials come along we may be lucky we have even one way to get it done.

There are as many ideas for getting people to Mars as there are ways of getting people across an ocean, from Kon-Tiki concepts up to supersonic airplane concepts.

The mission will have to be wrapped around the technology available, and a mission around many low-cost small launches will look completely different from a mission depending on one or two huge expensive launches.

It’s educational to look back at how most scientists and engineers thought we would reach the Moon back in the 1950s. Based on hundreds of low-cost reusable orbital launches, a large orbiting space station, and a robust space construction capability, it bore no relation to the eventual Apollo program. But unlike Apollo, it would have resulted in a permanent space infrastructure.

Then you have to decide what the mission actually is. Land people on Mars right away and bring them back? Land them and set up permanent colonies? Build orbital stations around Mars (maybe on one of the Martian moons) and work up to a landing later (my personal favorite)? There are many possibilities, all with different requirements and different timelines. Again, the available technology is a major driver. For example, it may be possible for current robotic technology to have a safe working habitat waiting for astronauts when we get there.

Key to any mission in space is lowering the cost of space transportation. You don’t need large cargoes if you can ship a lot of them, and you don’t need fancy life support for a colony if you have a reliable, redundant supply flow. The entire city of Honolulu was built by stuff that would fit on boats. But it was a LOT of boats.

Remember there’s a lot going on outside of NASA. When the Orion capsule landed this week, SpaceX had already launched and recovered their Dragon capsule six times, and it too is designed for high-speed re-entries from lunar or planetary trajectories.