New Sun, Moon and X-Ray Missions // Mars Colony Size Limit // Starship's Ready

I could live on Mars alone with no other help from humanity. After all, I hear one can grow Hella potatoes!

I don't "deeply disagree" But I would bet you're wrong. We humans can make amazing things happen

This is a conversation we need to keep having now. However I believe the ultimate way forward for humanity in space is by crating a hybrid human/robot. We need to figure out a way to upload the human experience as best we can into the closet thing we can come up with to a synthetic human brain recreation. At least until we can get to another habitable star system which will take longer than any humans can live. These hybrids would not require food and oxygen which would take a lot of space and resources to create, nor perfect temperature conditions planet. Once they arrived on a world they could create humans with DNA, or unfreeze through kryogenics. Did I watch way to much Sci Fi ? Maybe!

II think there are two different minimum viable systems problems here. The minimum viable industrial stack that can sustain itself. And the minimum ecological and social system that can sustain itself. I’ve thought much more about the industrial side rather than the biological side, so I will stick to that aspect. Looking at the vast array of items we produce on Earth and the range of processes we use today is misleading. Our industrial system is optimized for commercial profit, not minimum viability. For minimum viable reproduction, processes \can be ugly and inefficient, so long as they produce a viable component in minimum steps. An example would be the proposal to produce solar cells on the Moon simply by electrical heating of moon dust. The resulting solar panels might be below state of the art, but if they can produce enough energy to replicate, that is enough. A colony that can produce all the structures, energy and computing it needs to replicate is viable, even if not economically efficient by earth standards. It could make fancier product later. I think we would learn a lot from the challenge that we wouldn’t likely learn staying on Earth. Its that change in perspective that for me justifies space exploration.

I don't see skill as a limiting factor as Martians will have access to most of humanity's collective knowledge. Instead, the main challenge will be to create a sustaible biosphere with all the necessary life forms.

Automation of manufacturing would reduce the human population need as long as sufficient skill sets existed to maintain the machinery. However, to create a self sustaining colony would likely need tens of thousands as a bare minimum, but as any population grows that create significant issues. There is no decay on Mars, so waste is an issue, as would be dead humans, these are fundamental issues that must be addressed. Realistically, I would suggest the bare minimum is around 5,000, but would suggest there is also a practical maximum per settlement due to energy production, food production, space and waste disposal. People are chucking numbers around without considering impacts.

Mars allows humanity to stretch. It may not be a destination, but the journey there and back will inspire a billion people. That is why we need you to continue to inspire us.

To create a self-sufficient Mars colony I think human reproduction would be an important consideration. Unless you have artificial wombs on the colony, you're going to have to replace people the old-fashioned way. How many fertile women would you need to have babies at what rate to balance the death rate? What would be the life expectancy of children born on a Mars colony? Would young women want to go live on a Mars colony if there was a possibility they would have to become baby-makers to keep the colony going? And all these children are not going to have skills to support the colony economy for many years. This all seems very problematic.