111–120 of 124 posts
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Many see this as the answer to the Fermi paradox. Any society on the path to being advanced enough to potentially leave their system probably gains the ability to destroy themselves before getting to that point. Short terms issues preventing long term gains.
One (terrifying) option is we are alone. There is no real reason to believe life is abundant in the universe. Even on Earth (the one place we know for sure can support life), life has only occurred once. Life may just be so much more rare than we think is possible.
We don't actually know that at all. It could have happened many times and one line won out, it could have been more of a diffuse process than a single event (picture how microbes share genetic material ~freely but even less structured), or there could be a ton of life out there on Earth that's from a completely different tree. We really have very little idea what's living around us.
Humanity’s greatest journey so far has only reached the closest world to us: the Moon ... in a universe that stretches endlessly in every direction and is seemingly infinite. It's kind of wild to think about: we might end up collapsing our own civilization before we ever make it beyond our solar system. At this point, I suspect the next real explorers won't be us, but probes carrying intelligent machines..our robotic…
Many see this as the answer to the Fermi paradox. Any society on the path to being advanced enough to potentially leave their system probably gains the ability to destroy themselves before getting to that point. Short terms issues preventing long term gains.
Earlier quoted context omitted.
One (terrifying) option is we are alone. There is no real reason to believe life is abundant in the universe. Even on Earth (the one place we know for sure can support life), life has only occurred once. Life may just be so much more rare than we think is possible.
> Even on Earth (the one place we know for sure can support life), life has only occurred once. We don't actually know that at all. It could have happened many times and one line won out, it could have been more of a diffuse process than a single event (picture how microbes share genetic material ~freely but even less structured), or there could be a ton of life out there on Earth that's from a completely different t…
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Like 10^200 years In 10^40 years it will barely have scratched the surface. Unless protons decay.
I'm imagining the sun going nova and the Voyagers surfing on that wave...
That’s really fast on cosmic scales. If it left when the dinosaurs were wiped out it would be 3,000 light years away by now. Even if it left as late as when humans arrived in North America it would be a light year away.
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Based on the interstellar density it will take a billion years to ablate just a millimetre off its outer layer. The chance of impacting anything larger than that is internal, same as an encounter with another star. In 40,000 years it will get to within 1.6 light years from a star, that’s such an unimaginable distance it’s irrelevant. In 100 million to 1 billion years you may not be able to recover audio from the gold…
“In 40,000 years it will get to within 1.6 light years from a star, that’s such an unimaginable distance it’s irrelevant.” On most human timescales that’s a long time, but here it’s only 0.004% of a billion years and in general stars are ~5 light years between closest stars in our neighborhood. If you assume zero significant impacts means it’s around in 100+ billion years there will be many vastly closer passes than…
Voyager may end up in a solar system briefly as a high speed extra solar object like Oumuamua, but the chance of it being close enough to suffer any physical affect would be small - think how small a target that would be and how rare stars are. To get within 1 light day would mean passing 100,000 stars within one light year. To get down to earth distance is something like 4 billion passes within a 1 light year distance.
Now sure predicting the future beyond say 100 billion years is tricky, and not something you could simulate, but for all intents and purposes the voyagers will continue long after Earth has died. It (and other craft on escape trajectories like new horizons and pioneers) will be the last remnants of human civilisation
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> Even on Earth (the one place we know for sure can support life), life has only occurred once. We don't actually know that at all. It could have happened many times and one line won out, it could have been more of a diffuse process than a single event (picture how microbes share genetic material ~freely but even less structured), or there could be a ton of life out there on Earth that's from a completely different t…
If there is a different tree of life right here on Earth and we don't know about it, that would cast doubt on our ability to detect life in worlds light years away. Also, if life had multiple false starts here on Earth, that does also suggest that it is very difficult to take hold even on the original Goldilocks planet. The idea that multiple versions of "life" co-developed and became a single strain is quite interes…
Hm, I don't think it does. The problem is vastly different. Here, on Earth the problem is: sift through all of life for some that's different than the rest. A _hard_ problem with how little of microscopic life we've cataloged completely and with how much of the volume of Earth we can't see.
The problem looking for life in the stars is more: find evidence of _any_ life, so radio signals or chemicals that can't reasonably come from anything else but biology. Those are hard as hell, but fundamentally different.
> Also, if life had multiple false starts here on Earth, that does also suggest that it is very difficult to take hold even on the original Goldilocks planet.
That would be interesting. I kind of guess it's less likely than some kind of winner-take-all outcompeting thing, but who knows. Life that we see is just very good at spreading, escaping and holding on tight.
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“In 40,000 years it will get to within 1.6 light years from a star, that’s such an unimaginable distance it’s irrelevant.” On most human timescales that’s a long time, but here it’s only 0.004% of a billion years and in general stars are ~5 light years between closest stars in our neighborhood. If you assume zero significant impacts means it’s around in 100+ billion years there will be many vastly closer passes than…
Not at light years. How many non-binary stars do we see colliding with other stars. They don’t. Even when andromeda runs into the Milky Way it won’t result in stars colliding. The chance of the sun colliding with another sun is somewhere in the 10^30 range. Voyager may end up in a solar system briefly as a high speed extra solar object like Oumuamua, but the chance of it being close enough to suffer any physical affe…
Ignoring gravity may be fine at 1.6 light years but a closer approach to even just say 2 light months means spending thousands of years much closer to the star which would matter here. So simple extrapolation based on random distribution of nearest approaches like you just proposed with that 100,000 star calculation is heavily biased in the wrong direction.
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That is one answer. Another possibility (the one I prefer, since this is mere speculation anyway) is that we are early.
Early as in we may have developed before any other civilizations? That's interesting. We're speculating of course, but what would explain us being the first after so much time – 13.8 billion years?
https://en.wikipedia.org/wiki/Firstborn_hypothesis https://en.wikipedia.org/wiki/Formation_and_evolution_of_the... https://en.wikipedia.org/wiki/Nebular_hypothesis https://en.wikipedia.org/wiki/Protoplanetary_disk
Now you could still say that surely there have been enough time for some advanced civilizations to form. And I would argue that we don't know that. At least we have not detected them, either due our instruments or unwillingness of the intelligent life to communicate to us.
There are of course many other explanations of the Fermi Paradox. But since its all unknown, its basically pick and choose. I choose to pick the nice option. There are however other nice options :) https://en.wikipedia.org/wiki/Fermi_paradox#Hypothetical_exp...
Humanity’s greatest journey so far has only reached the closest world to us: the Moon ... in a universe that stretches endlessly in every direction and is seemingly infinite. It's kind of wild to think about: we might end up collapsing our own civilization before we ever make it beyond our solar system. At this point, I suspect the next real explorers won't be us, but probes carrying intelligent machines..our robotic…