TO MARS ORBIT

Yes, I think so - to orbit anyway - maybe not to the surface. I think the thing that would really spur interest in Mars would be if ExoMars or one of our landers finds life on Mars and if that life is interestingly different from Earth life.

That would be of huge interest - not just to colonization enthusiasts - but also for medicine, nanotech - and think how much of our lives depends on products created by life processes. The payback from studying a fundamentally different form of life could be immense - easily offset cost of a human mission to Mars orbit.

You wouldn't land because landing would contaminate Mars and destroy much of the interest of it for life studies, biology etc. But if you are in a close up orbit around Mars then you can drive telerobots on the surface and it is in many ways better than being there in person - no need to wear spacesuits - automatically enhanced vision - and everything you see and do on Mars automatically streamed, HD stereo surely - back to Earth for us to enjoy as well - as that is how you see Mars yourself.

Would be like using the Oculus rift, and the virtuix omni - but on a real planet, Mars, instead of a virtual world.

And - the evidence so far is quite in favour of finding life on Mars - past life especially - and if there was life on the planet in the past, hard to see it becoming extinct if it got anywhere as far as evolution on the Earth - so should still be there today and are habitats on the surface where it could be living, mostly in low concentrations of just a few microbes probably mainly hidden beneath the surface, possibly some more complex lichen like plants - may not seem that exciting - but it could be

• fundamentaly different XNA instead of DNA
• or, still DNA based but different "engine" turning that into proteins, metabolizing etc
• or, an early form of life, telling us something about the missing pages in the book of evolution, earliest forms of life probably 40 nm or less, present day machinery for life can't fit into less than 200 nm
• or, pretty much like modern life - but with different metabolic pathways, or things like - different pigments for photosynthesis, different ways to adapt and protect against ionizing radiation or UV etc.
• or - fundamentally identical to Earth life in all respects

Of all those last is the least interesting - but is also, most would say, least likely because there has been little contact between the planets for billions of years, some possibility of very occasional (perhaps every few tens of millions of years) transfer of some remarkable species on meteorites but not even that known for sure.

If it was any of the others - the effect for understanding of biology and potential new applications also - would be vast, pretty much unlimited. Even based on hard nosed economics, it would be well worth the punt to find out.

TO THE MARS SURFACE

Depends what happens I think in some scenarios, it might never happen.

One thing we might discover on Mars is life that is based on a fundamentally different biochemistry. Could be XNA - not based on DNA. Could be earlier forms of life, smaller than any known microbe on the Earth. Could be different in more subtle ways - unusual biochemistry, different pigments for photosynthesis - more resistant to cosmic radiation, ultraviolet and vacuum conditions than the equivalent forms on Earth.

Also we might find there is no life on Mars - habitats - but no life in them. That's also valuable to study - because of similarity to Earth - so you can see what the effect is of life - by studying a planet without life. Also makes it far easier to study traces of past life on Mars - without interference of the biproducts of present day life.

Those things might all make Mars more valuable to us uninhabited than as a colony - especially since it's not actually that good a place for humans to live - and since - we also have options to build habitats in free space which have many advantages.

It's a decision we'll make at some point in the future. But at present I'd say we don't know enough about Mars to make that decision - especially since it is also an irreversible one. Problem is - if you introduce lifeforms to a planet - even microbial life - that's never been on that planet before - and it starts to reproduce - and if there is some way of spreading it globally (on Mars you have the atmosphere and the dust storms) - then you can never reverse that with present day technology at least.

If that happens - then we might still colonize the Moon or space. But personally - I think no great hurry to colonize .Explore yes. Humans can be valuable explorers of the solar system. But it's like Antarctica - it's not a desirable place for humans to live without a huge amount of work - I think for a long time we'll go to space for other reasons, not to colonize.

Certainly no "little house in the Prairie" type colonization - nowhere in space that humans could live without technology - if anything happens to your habitat, you are dead - no future in trying to escape from it into the vacuum of space that surrounds you in all directions. And in most locations in space you need hugely expensive massively constructed houses that can withstand tons of pressure per square meter and are covered with several meters of cosmic radiation shielding.

Only way around that, that I can see - which we might do some day are

• Big habitats in space - so large that you can build houses inside of them (like the Stanford Torus) - if they could be reasonably low maintenance - like - you build the big habitat and then with a reasonable level of maintenance it can last indefinitely into the future for centuries, even millennia - not just for the three or four decades of a space station - then perhaps they could be worth colonizing
• Atmosphere of Venus - could build "Cloud nine" colonies. We could build cities that float in the atmosphere of Earth - but nobody bothers because it's easier to build cities on the ground. But in space, the easiest place to build cities might be floating clouds in the atmosphere of Venus given that nowhere is it anywhere like as easy as to build on the ground here on Earth.
• Subterranean dwelling in caves on the Moon or on Mars. As with the big Stanford Toruses - perhaps large enough caves could be low enough maintenance to be worth inhabiting.

Of those three - the free space habitats are relevant to Mars - you could live in big habitats that are in orbit around Mars - and long term - as artificial gravity - ideal conditions - might be low maintenance if big enough - then - might be practical to live in those long term - and then could explore the surface of Mars via telepresence.

As for terraforming Mars - that's a centuries long high technology project if possible at all, which nobody knows. Far easier to build a Stanford torus in space - you can do that in decades - not thousands of years - and would cost far less also of course.

Living underground on Mars - is a possibility - but - then you have the big issue of contamination of Mars with Earth life. I know it never gets mentioned in the Mars colonization news stories - but if the time comes that someone has to work out detailed plans and proposals and explain how they will keep Mars free of contamination (as required under international law) - I think will turn out to be a major issue that simply can't be solved to sufficient confidence with present technology within the limits of what we currently know about Mars.

Also nobody knows if humans can survive long term in Mars gravity. Life evolved in full gravity and there are many changes in the body in low g which ARE NOT EVOLVED ADAPATATIONS TO ZERO G - but are just the body not functioning right in zero g, things just going wrong because it's not adapted to zero g.

When the first humans went into space in the 1960s nobody knew if we could survive as long as an hour in zero g. Is now known we can survive months and a few Russian cosmonauts have lived for well over a year in zero g (so far no American astronaut has yet spent a year in zero g). But it's unknown whether or not a human can survive two years in zero g.

There is similar uncertainty about Mars g. When you hear Mars colonization enthusiasts saying that humans in Mars g would adapt to be healthy in Mars conditions - that is just hopeful thinking at present, with no scientific evidence to back it up. Human body is far too complex to simulate - and the experiment has never been done.

If you ask me to guess the future, project as best I can from present day knowledge - say - 50 to 100 years from now - I would see - perhaps human settlements around Mars - mainly there for study of the planet - a bit like the settlements in Antarctica - and tourist settlements on the Moon - or in orbit around it - and around Earth - and could well be similar interplanetary scientific explorations of the rest of the solar system. Just possibly might have cloud colonies in Venus.

But if there are any attempts to colonize - without any other reason to be there except just to colonize - I expect those attempts to fail simply because nobody will want to keep paying the billions of dollars a year needed.

Because any attempt at a colony - think of something like the ISS - not something like a log cabin in the woods - huge expensive thing that needs to be supplied frequently from Earth, massively engineered - and the modules need to be replaced every few decades. It's just not going to be worth it for an ordinary house dweller.

That is, except for the really big super- habitats like Stanford Torus could make it worth while if you can find a way to fund them - and they can be sufficiently low maintenance. Original Stanford Torus idea was to have 10,000 people in space there making solar power satellites and that's how they would pay for themselves, beaming energy back to Earth. Not sure that would work today - but you need something like that to pay for it.

If there was some big project to build them - could have a viable Stanford Torus or Venus "Cloud Nine" - indeed if the US had decided to build the Stanford Torus in the 1970s - which it could have - within e.g. its Defense budget though far more expensive than Apollo - we could have it there already - and might also have prevented the energy crisis and global warming by beaming solar power to Earth equal to all our power needs - if the Stanford academics who worked out the plan got the design details right.

See also my Case For Moon First