I see some skepticism about in regards to establishing anything outside of Earth.

Can i put to those people: The long stretch between the wheel and the engine, the engine and the aeroplane, and the aeroplane and the Moon landing.

It seems to me all we need is time to solve thsee problems (obviously, that ignores what happens within that time - but using hte above as a reference, surely we can be relatively confident humans, over time, will solve problems we are set to solve).

Can i put to those people: The long stretch between the wheel and the engine, the engine and the aeroplane, and the aeroplane and the Moon landing. — AmadeusD

Yeah, I'm one. The analogy doesn't hold, though. Mars is a possibility, as it is within some kind of striking distance. But even so, the problems involved in travelling there, let alone setting up habitable environments, are enormous.

But anything outside the solar system is another matter altogether. The times and distances involved are unthinkably huge. The nearest star system, Proxima Centauri, is 4.25 light years away and any kind of travel that covers those distances would take millions of years. That is 40 trillion kilometres, give or take. To give a sense of scale: even at 100,000 km/h (far faster than any crewed spacecraft has ever flown), the trip would take roughly 45 million years.

And even if propulsion and life-support challenges could somehow be overcome, human interstellar travel faces a fundamental biological barrier in the form of radiation exposure. Beyond Earth’s magnetosphere and the Sun’s heliosphere — crews would be continuously bombarded by high-energy galactic cosmic rays and episodic solar particle events. These particles penetrate most conventional shielding, generate secondary radiation within spacecraft materials, and accumulate irreversible damage to DNA, nervous tissue, and immune systems over time. Measured radiation doses on a Mars trajectory already approach the upper limits considered acceptable for astronaut careers; over interstellar timescales of decades or centuries the cumulative exposure would almost certainly exceed survivable thresholds. In this sense, radiation is not merely an engineering inconvenience but a hard biological constraint on human deep-space travel.

There was an ambitious idea to send ultra-light computer-powered systems to Proxima Centauri using laser-guided sails, Breakhrough Starshot. It sounds at least feasible, if not actually possible. But even that is effectively on hold.

Thanks mate - good stuff. I understand the points of resistance - but they would have been present prior to those other leaps forward, as I understand. People refused to believe the Wright brothers succeeded for a long time (relatively).

But even so, the problems involved in travelling there, let alone setting up habitable environments, are enormous. — Wayfarer

They appears to be shrinking. Which is my point. As time goes on, these sorts of things will crop up, and eventually viable methods will be to hand. Its speculative, but based on prior patterns of human invention/progress.

But anything outside the solar system is another matter altogether. — Wayfarer

Definitely. The timeline I imagine here is more like 1000 years. Not say, 150 as I tend toward that range for Mars or even visiting Pluto tbh.

However, there are, as I understand, some theoretically reasonable attempts at an equivalent of a warp drive/wormhole/gravity drive type of thing. Clearly, not open to engineering currently so its fair to reject the concept. But again, with the passage of time I see them becoming so, given their consistency with theory. To be clear again, this is speculative and I think we have reason for hope.

human interstellar travel faces a fundamental biological barrier in the form of radiation exposure — Wayfarer

As above, yes, currently. I am speculating into the far future and don't see a reason to assume we will never overcome these challenges - particularly as it'll be incremental. If we've figured out how to populate Mars, this may not seem so far fetched by lets say 2300. Ultimately, this is just for fun really.

In this sense, radiation is not merely an engineering inconvenience but a hard biological constraint on human deep-space travel. — Wayfarer

Sure, among the present available options. But we could certainly come upon a technique for deep-sleep which overcomes the radiation issue. Other things have to work for that to be anything but ridiculous. Granted. Speculative...

It sounds at least feasible — Wayfarer

I think that is all we will ever see in our lifetimes. Something feasible but out of reach.

warp drive/wormhole/gravity drive type of thin — AmadeusD

I respectifully think a lot of these ideas are science fiction. Which has, after all, seeped into the culture through nearly a century of cinematic memes. But if the Earth can't even get it together to agree to a treaty to prevent climate catastrophe, what are the odds of pulling together the kind of massive global effort required for planetary expansion. All the people spruking it - Bezos and Musk, mainly - are the top 1% of the top 1%, and they stand also to be the chief finacial beneficiaries of the whole endeavour, such as it is.

At risk of inviting vitriol, I don't think we're at risk of a catastrophe so its hard to use that analogy :P

But yeah, fair enough. These theoretics are so intensely out of reach that's a reasonable take.

I don't think we're at risk of a catastrophe — AmadeusD

Well, I admire your optimism. The Doomsday Clock was last set 28th Jan 2025, at 89 seconds before midnight.

Personally, taking that seriously is a bit of a orange flag.

C'est la vie :P

They're not cranks. It's published by the Union of Atomic Scientists.

Founded in 1945 by Albert Einstein, J. Robert Oppenheimer, and University of Chicago scientists who helped develop the first atomic weapons in the Manhattan Project, the Bulletin of the Atomic Scientists created the Doomsday Clock two years later, using the imagery of apocalypse (midnight) and the contemporary idiom of nuclear explosion (countdown to zero) to convey threats to humanity and the planet. The Doomsday Clock is set every year by the Bulletin’s Science and Security Board in consultation with its Board of Sponsors, which includes nine Nobel laureates. The Clock has become a universally recognized indicator of the world’s vulnerability to global catastrophe caused by man-made technologies.

Last week, Putin fired a nuclear-capable missile into Ukraine.

Oh, no I'm aware they aren't cranks. They aren't required to be cranks for it to be bollocks.

If it ever gets to Zero, you can eat my hat :)

There'll be no hats. :yikes:

Anyway - my basic point is still, there's an awful lot of basic stuff that needs doing here on Earth, before 'fixing our gaze on distant worlds'.

Yep, definitely! :pray: