Chart of the Milky Way Includes More Than 1B Stars
scientificamerican.com
scientificamerican.com
There's an estimated 100 billion planets in the Milky Way alone, and who knows how many in the Andromeda galaxy.
There could be another satellite somewhere in this galaxy charting space just like this and we'd just be a bright dot to them among billions of other bright dots.
The Universe is teeming with galaxies, which are teeming with planets. Given what we know now it is likely that they are teeming with life (organisms in a process of self-sustaining and self-generated action) as well.
https://www.theatlantic.com/science/archive/2018/03/human-ex...
About how we may expect life to be more prevalent than it is because our own existence is so miraculous. Though the other side is - if the universe is so large, with so many planets, then there may be a chance that there's life out there that's just as incredibly lucky as us.
Ponder this: how early did life appear on Earth? what later cataclysmic events did it survive through the next several billions of years? how many living organisms are there on Earth at the moment?
Finally, how you imagine life can exist or can appear is not equivalent to the facts of life on Earth, let alone in the entire Universe.
And what if a lot of intelligent species run into this problem? Where the level of knowledge and power they amass far outstrips what they've evolved to responsibly handle. And the result is intelligent species often manage to destroy themselves before they become wise enough to avoid that.
I often think downvoting is overdone, though.
Really? I haven't seen that at all. If you're talking about Christianity and the whole "end times" stuff, that's a little different: that isn't humanity "driving itself to extinction", that's some deity deciding that humans are bad and proactively eliminating them. I don't see that as the same thing at all.
In fact, why I said this seemed to be offending peoples' religious ideals is that I think the idea of humans making themselves extinct directly counters this religious idea that a deity is the one in charge of humans' fate. To them, if humans are all eliminated, it can't possibly be because humans did it to themselves (as this is what they'd call a "humanistic" or "secular" idea), but could only happen because their deity made it so. And conversely, as long as humans are "good" enough (meaning they worship the deity enough, nothing about them wrecking their environment or obliterating themselves with nuclear weapons) then the deity will protect them from their own mistakes.
It's an abstract concept that is analogous to a single human, that is supposed to exist without a specific location in space and time, and has free will, causes things to happen and/or is blamed for them. And I see the same lack of empirical evidence for the concept.
So, yes, you may not see it as the same thing, but I quite definitely do.
We're the most adaptable species ever to live on this planet . There are 8 billion of us on every continent except Antarctica, and we've found ways to codify and share our collective knowledge.
Climate disasters, widespread thermonuclear wars, etc would be horrifying and would likely kill a great many or even a majority of humans. But even that wouldn't do much more than slow us down a few hundred years.
Even an a massive impact from space on the scale of the Chicxulub impact would kill off most people, and collapse civilization - but we'd rise again in less than a thousand years.
It's very hard to think of a scenario that would actually end us. One thing I've speculated about is maybe we unlock some awful power that we can't control. For example, if it were easy for anybody to distill antimatter in their garage in large quantities. Because there are always going to be those among us who want to burn it all down and who would destroy everything if they could. In a hypothetical world where terrorists and rampagers attacked with kilograms of antimatter, that might make it difficult to maintain a level of civilization for long periods of time.
Would we though? I am not so sure starting from scratch is going to possible. For example, all the easy oil is gone. All the easy mining, is gone. We can get at it because we have the technology.
If 99% of the human species was wiped out, yes we would continue to exist, but I would not expect many great civilisations to flourish again
> All the easy mining, is gone.
This bit is wrong, though. You can literally walk through a demolition site and pick up rebar and aluminum by the ton. Access to a single ancient reactor would give you the equivalent of decades of mining from any single uranium site. All our city building has had the effect of concentrating easily exploitable "ore" resources, not depleting them.
>Access to a single ancient reactor would give you the equivalent of decades of mining from any single uranium site
What could is uranium to destroyed civilisation where all previous knowledge has been lost? I don't think future post civilisation peoples are going to be reconstructing a nuclear reactor from wood.
>You can literally walk through a demolition site and pick up rebar and aluminum by the ton
Post civilisation people are not going to have much use for demolished materials. Yes with modern technology we could reuse it. But how will they use it? I've seen a build demolished in the third world. People came and got the pieces of rebar true, hammered the concrete off it, but only to sell, not to use. I don't really think in a post civ world it would be of much use
> It's not impossible to imagine a future society skipping liquid fuels (and most of aviation) and still making its way to the renewable revolution.
Impossible? Perhaps not, but still very very unlikely. For decades after the event, survival will be all encompassing. Knowledge will pretty much have disappeared. You talk about skipping liquid fuels and aviation and going straight to renewables. First people will need to invent electricity again - everything will need to be "invented" again from a much weaker starting point. I just don't see it happening. Much more probable it is the end of human civilisations / humans as the dominant species on this planet
Again, you have completely lost me. Can you explain again why you think it's easier to dig up and smelt natural iron ores (or copper, or whatever) than it is to find an old rusty engine block or electric motor and just use that? Civilization needs metal to develop, in this example, not "mining". And ours has already done the mining!
The oil is gone, but coal is still easy to access. We can bootstrap off a second coal industrial revolution. And every person who've been through high school knows the principles involved in generating power from coal, though might be lacking in the actual techniques.
> but only to sell, not to use
You've proved there's buyers who would find a use for it.
You seem to be falling into the romantic view of post apocalyptic event. The world doesn't stay the same as it is now, just with the people gone. There is no one to buy your scrap metal. There is no more organisation, there is no more nothing.
> And every person who've been through high school knows the principles involved in generating power from coal
No they don't. They may know coal can be involved, but they have no idea how to take coal and make electricity. I assume you are a technical person working in a technical role. Go to your local supermarket and ask the person at the till for the basic principles involved.
There is plenty of information available today that allows one to rebuild some level of technology very quickly.
> I have a friend who has for decades run his own little metal furnaces. By comparison to the modern industrial refining processes, his are primitive. But they are easily built and work well for the individual.
Sure, but how many people have this knowledge now? How many people will be left with this knowledge after:
a) the event itself b) after years of struggling to survive and finally being able to more than subsist
First priority food and shelter. Food, you can scavenge supermarkets, but eventually it will run out. You will need to grow your food by hand. You will need to find seed and be successful otherwise it is hunter gatherer lifestyle, with assumed hunting is minimal as whatever wiped out 99% of humanity did the same to other animal species.
But lets say you found a good piece of land where you could survive, it would take years. Lets suppose you were one of the few people who knew how to build a furnace. Are you going to leave your patch of land to go wondering in the remnants of what was left of the city to get some scrap metal to carry back? I don't see it happening. Then in a generation of what was was is forgotton
I'm not sure we've been around long enough for such a bold claim. Afaik there's plenty of life on Earth that outdates our existence by magnitudes.
If you are talking about species to "ever live on this planet", then how long a species has been around being a pretty big factor in determining how adaptable a species is.
And in that regard, homo sapiens is rather a newcomer. Even our ancestors have only been around for a meager six million years.
While other species, many of them oceanic, have been around for hundreds of millions of years like sponges (580 million years) Jelly Fish (550 million years). Cyanobacterias are actually the oldest known living system in the world, originating 2.8 billion years ago, technically the oldest life on earth.
Compared to those, humanities existence is literally just a second on the clock of Earths history.
I would agree that an interplanetary/interstellar civilization is something that may never come to pass, but I don't see it as a judgement on the capacity of particular life on earth to adapt, but rather a result of the physical laws that constrain all life, particularly delta-V and the speed of light.
For that matter, the typical planet with life could be too large and have too thick an atmosphere for space travel or astronomy and thus never have any idea the rest of the universe exists. That wouldn't necessarily mean life was limited to single cells.
[1] I once counted the grains in 1 cm³, there were pretty much exactly 8000 of them ignoring the very fine powder from crushed grains. 1 m³ of table salt gives you pretty much one grain of salt for every human on earth.
So your 500 sq ft apartment is filled to a height of 3 feet with salt. That is 400 billion grains of salt.
It's also downloadable in full res [2]. Maybe use the torrent option to save their poor servers.
[1] https://www.spacetelescope.org/images/heic1502a/zoomable
This video is a really good example of how to sort of wrap your head around just that: https://www.youtube.com/watch?v=Kj4524AAZdE
https://www.astro.princeton.edu/universe/
I finally got round to printing a two metre tall version of this to hang in my hall a couple of weeks ago!
gravitational lensing by Sun, just need to put the telescope at least 550 AU from the Sun.
https://www.airspacemag.com/daily-planet/ultimate-space-tele...
"And using the Sun as a lens would result in much greater magnification. Instead of a single pixel or two, astronomers would get images of 1,000 x 1,000 pixels from exoplanets 30 parsecs, or about 100 light years, away. That translates to a resolution of about 10 kilometers on the planet’s surface, better than what the Hubble Space Telescope can see on Mars, which would allow us to make out continents and other surface features."
To the GGP point of light speed limit - that is only true for static fixed spacetime. The spacetime expansion/contraction doesn't seem to have that limit (this is how we have far-far galaxies receding from us at the speeds higher than c). Just an issue of engineering that into a practical drive ...
Similarly, we are not aware of any physics-based reason that prevent the design, construction and maintenance of computing substrates that renew themselves over billions of years. There are certainly political, cultural, social, even energy limitations, but nothing quite as hard as the c limit.
So theoretically, we can hope to even in this reality to eventually create versions of our selves that reside in computing substrates and "wake up" for "interesting" events along a multi-million year journey. Perhaps they run in a low-power mode, where 1 day in real universe == 1 second in the substrate. In that context, even if we never go faster in that future than our current technology's Juno space probe, a trip to Alpha Centauri is "only" 17,785.27 years, or 12.35 years subjective substrate time, enough to get excited about and study the torrent of increasingly-fine-grained data pouring in from the real world about the destination.
If the galaxy is relatively teeming with these compute substrate hibernation ships, then that presents interesting possible resolutions to the Fermi Paradox: what we are doing today on Earth is not "interesting" enough to the automation on these alien ships, or we are deemed interesting, but even the nearest ship within our light/EM cone is still thousands to tens of thousands of years away.
It gets even more interesting if we figure out how to "decant" substrate consciousnesses into physical bodies.
Even at that glacially-slow crawl of the Juno space probe, it would still take "only" 383,551,218 years to traverse the Milky Way's 100,000 light years. Put up against the ~13 billion years of the Milky Way's existence, that means spreading across the Milky Way is still within the realm of not-ruled-out-by-physics.
https://www.eveonline.com/article/introducing-time-dilation-...
Google says 250 +/- 150 bn. I think low...