When the sun dies, could life survive on the Jupiter ocean moon Europa?
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A possible problem is that Jupiter itself could destabilize Earth's new orbit. Possibly putting Earth into orbit around Jupiter as an additional moon would be a solution, but if not, I think we could solve that problem by removing Jupiter. If we drop it into the Sun, we can gain all of its orbital energy in the process.
https://longnow.org/ideas/long-now-years-five-digit-dates-an...
Zager & Evans - In the Year 2525
https://www.youtube.com/watch?v=zKQfxi8V5FA
Now it's been ten thousand years, man has cried a billion tears
For what, he never knew, now man's reign is through
But through eternal night, the twinkling of starlight
So very far away, maybe it's only yesterday
Long before and after that religion became dominant, many people have used different calendar systems - and many still do. Rome was founded in 753 BCE, and the Western Roman Empire fell around 476 CE. That's over 1200 years.
It's more likely that another "year zero" event will happen in less than 8000 years. If the history survives that, we will probably just call the current era "Gregorian" or so.
But now we have a single global standard, I think there is a huge amount of inertia against changing it - it is baked into untold millions of computer systems and business processes now.
I think the most likely way it might change would be (a) if humanity collapsed back to a premodern civilisation, and later recovered; or (b) some new culture/religion became globally dominant which demanded the calendar be changed.
Personally, I’m sceptical (a) is going to happen in the next few thousand years. I think the most likely scenarios are (i) technological modernity survives, (ii) humanity goes extinct completely, (iii) a more moderate collapse in which things get very messy but don’t go all the way back to the premodern era. I think all three are more likely than the kind of complete and extended collapse then eventual recovery which would be most likely to reboot the calendar into a new and different global standard.
I don’t think odds of (b) are high-it would require not just a new dominant culture, but also one which felt very strongly about wiping out all traces of the old calendar. Suppose 1000 years from now, 99% of humans are devout Muslims-I personally think that’s rather unlikely to happen, but anything is possible-would that trigger the current year numbering to be replaced by the Islamic one? I’m sceptical-all Muslim majority countries currently heavily use the Gregorian calendar for business use, computer systems, etc, and they don’t have a theological issue with that, so I’m sceptical they’d feel the need to change even if Islam became the globally dominant culture. And this isn’t a new thing in history-many historical Islamic empires continued the use of pre-Islamic calendars in parallel with the Islamic, especially since the Islamic calendar, being purely lunar, was less than ideal for agricultural use.
We have two global standards, both from the Western Christian tradition. The Gregorian calendar, and Unix time. Order of magnitude, they're probably baked into the same number of processes.
And Thompson and Ritchie grew up and worked in a majority-Christian country: their individual faith doesn't have much to do with it.
Now, the common AD/CE year numbering is obviously Christian in motivation, but that’s technically distinct from the Gregorian calendar-the Julian calendar historically used other year numbering systems too (ab urbe condita, anno Diocletiani aka anno martyrum, anno mundi), and the Gregorian calendar itself doesn’t care what numbers you assign to years beyond modulo 400 - you could replace 2025 with 2425 or 12025 and it would still work fine. But that’s the thing, Unix time doesn’t care whether 1970 is called 1970 or 1570 or 2370 or 11970, only how distant you are from it - so it isn’t really tied to our Christianity-inspired year numbering, only to 1970-01-01T00:00:00Z as an instant
I think CE + 10,000 - called “Holocene Era” (HE), also sometimes expanded Human Era or Historical Era - is a good proposal - high compatibility with CE (you can just pretend 2025 is missing the leading digit), makes all dates from recorded human history positive. Okay, is ambiguous in that 2025 CE might get confused with 2025 HE (= -7975 CE = 7976 BCE), but in practice that’s unlikely since that’s prehistorical and essentially nothing (outside astronomy) from that long ago can be dated to a year’s accuracy anyway
https://en.wikipedia.org/wiki/BSD_Daemon
>The copyright on the official BSD Daemon images is owned by Marshall Kirk McKusick, a very early BSD developer who worked with Bill Joy. McKusick has freely licensed the mascot for individual "personal use within the bounds of good taste (an example of bad taste was a picture of the BSD Daemon blowtorching a Solaris logo)."[ Any use requires both a copyright notice and attribution.
Blowtorching a Solaris logo sounds like it's in good taste to me! Just not blowing it without a torch.
An Earth year is a year only on Earth.
I think for humans on Mars, the local day-night cycle would likely be much more important than local seasonal cycles. Plus for a long time they’d be dependent on Earth (financially, politically, etc), and Earth years are a natural unit of Earth-centric planning, plus they’d see themselves as part of Earth-centric human history. And maybe eventually they’ll wean themselves off their dependence on Earth, but that would likely take centuries, by which time such a hybrid calendar may have become deeply embedded in Martian culture, and the use of the Earth year might endure long after the original motivations for it ceased to apply
So I could see our current Earth-centric year numbering system being maintained as humans spread out through our solar system. And if eventually we spread to other star systems, we might take that with us too
The Antarctica already is an interesting case study. Different time zones are being used mostly due to territorial claims, but south of 80deg, UTC is dominant. Each base might be using their own, local equivalent of a day/night cycle. Connectivity is extremely limited; pastime Internet access makes 56k modems look like a luxury. Interesting reading: https://brr.fyi/
Near-term, we will most likely colonize the Moon long before Mars; shorter missions to lunar bases might happen in the upcoming decades. The Moon doesn't have a day/night cycle at all. It may have a similar effect on local, "human" timekeeping; people might talk with other local colonies as much as they do with mission control, and will rely on each other for immediate support. There are existing proposals for an LTC, which is both an engineering and a political challenge. One of the requirements stated in the current proposals already includes the handling of extended periods during which independence from UTC must be maintained - computers will run almost everything after all. Even access to the Internet will require a store-and-forward protocol, which will break the current webapp models. It won't affect how the years are being counted, but that's a lot of precedent even if just for technical and survivability reasons.
Any kind of travel from Earth to Mars will have to be scheduled years in advance, and takes hundreds of days at least for unmanned missions. The colonies will need a significant degree of independence for basic survivability: food, oxygen, recycling, production of maintenance parts, etc. Some may specialize and rely on each other. Even information travels for ~3m to ~20m, and there's a blind spot when the two planets are on the opposites of the Sun. Staff involved in existing missions are already carrying customized timepieces to track both planets' solar cycles. Human missions will likely be one-way trips for a very long time; several new generations may pass. We will have to figure out how to deal with the lower gravity too, which may require new science.
On the other hand, early colonies will likely remain subterranean (fun stuff like cosmic radiation), perhaps until we can figure out new materials. Big terraforming projects will require solving the unknown unknowns. I think it's too early to speculate, but eight millennia is a heck of a long time.
How did you come up with dropping Jupiter into the sun being a net energy producing operation? You have to cancel out around 10^35 J of kinetic energy to drop it from its orbit, and that is real work. How do you get that 10^35 J back? (Ignoring that from your own math, that E35J is around 100,000 years of the sun's total energy output).
Not an orbital mechanicist though.
Maybe you scoop up big balloons of gas, slingshot them to Mercury with a tether, catch them with another tether on the dark side of Mercury to decelerate them (thus generating electricity which you use to make some kind of fuel), and toss them Sunwards from there.
Or maybe you use an electromagnetic mass driver in the Asteroid Belt to launch an unbelievable number of small rocky masses to a gravitational slingshot around Jupiter back to the same mass driver again, but at a higher velocity, so they generate electric power when it catches them before launching them again. Each mass goes through this circuit tens of thousands of times.
There are lots of possibilities.
However, smaller O'Neill-cylinder space stations are feasible even with just steel cables, and I look forward to a future where the vast majority of inhabited land area is in such contraptions. It will take at least 30 years, probably more like 300. The danger is that we collectively take a more destructive course.
I don't think there is a clear trend toward this goal at all.
Extrapolating current trends, we are fairly likely to peak in total population as a species long we become space-constrained on earth; more remote living space is pretty cheap in basically every industrialized country right now, and living in a conventional house in the boonies is like ten orders of magnitude easier than making anything extraterrestrial work (neither climate change nor even global nuclear war is enough to flip that).
Sure, people might like the concept of space colonization, but we're not seeing significant amounts of people living on boats in the Atlantic, so I would not expect to see people living on spaceships within the next centuries, either...
Probably you're right that most people will choose to die on the same planet they're born on. Most people today choose to die in the same city they were born in, and most coconuts sprout, if at all, within a few meters of the tree they fell from.
That doesn't mean that coconuts' ability to float across the ocean is inconsequential to coconut species distribution. It only takes one coconut making landfall on a barren atoll to start a new coconut grove.
There are, in fact, a significant number of people who live on boats. There would be many more if the boats weren't dependent on docking to refuel.
It's a mistake to extrapolate from current trends when it comes to exponentially growing phenomena. In April of 02020 covid had killed less than 1000 people after six months. In 01770 two million years of human beings had managed to speed up their transportation from the speed of a marathon runner to the speed of a racehorse. You have to look at the underlying dynamics, and even then what you often learn is that the future is very uncertain.
I like your optimism and would love to see colonies in space, but I think it is overly tempting to consider settling space akin to European colonization of America, when it is more similar to settling on the high seas/Antarctica (right now)-- technically feasible for decades or even centuries, but not really happening simply because of lacking incentives (and the incentive structure looks sadly even worse for settling in space than either of those to me).
The article isn’t trying to make science-fiction predictions, it’s simply explaining how things are expected to go according to the workings of the Universe. The article also isn’t suggesting humans will go to Europa to survive, only that life could theoretically develop and persist there.
We can’t even let our fellow humans live. Hatred and division is growing, and we’re ever more worshipping and giving power to destructive, selfish, science-denying, power-hungry maniacs with access to world-destroying technology. And you think there’s any chance we’ll all agree and unite to move the whole planet? It would be nonsensical for the article to even hint at entertainment that scenario in any serious capacity, and it would have been rightly dismissed by most people if it did.
Undoubtedly, if there are still humans after a few hundred million years, they will disagree about exactly what orbit Earth should be in, but that doesn't mean it will stay in the same orbit until after its oceans boil dry.
Which is not my argument. At all. You’re talking about if we can, I’m talking about if we will. The article—again, rightly—explains what we predict is going to happen according to the information we have. It’s trying to be a scientific-minded article, not a science-fiction article. By your token, anyone could make up any technology to contradict the article, which is not a productive discussion.
> the kind of global agreement you're dismissing as unachievable.
I disagree it’s the same kind of agreement. The difference in magnitude and investment is gargantuan to the point it’s another category altogether. Like a group deciding where they’ll go out to dinner VS deciding which country they’ll all move to. Both require mutual agreement for the same group to advance, but that’s where the similarities end.
> Undoubtedly, if there are still humans after a few hundred million years
Which is a big if. You can’t in good faith flout “just move Earth further from the Sun” as if it was something routine without considering all the very real and very big obstacles which are in our way right now, billions of years before your proposed scenario.
The crux of my point is merely that your criticism of the article is unwarranted. Sure, phantasise about any any possible approaches to the problem you can think of, but acting like the article somehow failed to consider those options is what I’m disagreeing with.
Yes, moving the Earth is a larger project than replacing CFCs. But the humans harness progressively larger amounts of power per capita over time, historically at the rate of about 1.2% per year. At that rate, a Dyson swarm will capture effectively all of the Sun's 48-petawatt output in six or seven hundred years, though I expect the rate to accelerate. That's over a billion times larger than the power required to move Earth to anywhere. If you were to distribute the Sun's power evenly to the world's current population, only 7 people (per generation) would need to pool their shares to achieve it. So the magnitude of investment is extremely manageable.
I'm not interested in the real and very big obstacles that are in your way right now. I'm interested in which of those obstacles will remain 400 million years from now. It seems irresponsible to speculate that humanity will remain collectively suicidal for such long spans of time—if nothing else, you'd expect the collectively-suicidal subpopulations to become scarcer over time.
Only the part that illuminates the earth can do us any good.
Well, that's clearly the part that is the lowest-effort to access, but on the timeline involved for concern about the Earth's biosphere being incinerated by changes to the Sun's size and output, there is plenty of time to develop means of leveraging more than the easy part.
It would be a shame to abandon her entirely, but don’t count on nostalgia to last for billions of years. We will have empires of people who never lived in Sol who think Good Riddance.
It'll be a while, though. There will certainly still be a long period of time where Earth is the most powerful by sheer inertia, no matter how fast space civilization develops.
Maybe that's because we don't have cultural traditions that identifiably connect us to that. (We probably do, but they're so deeply ingrained that we can't even identify them as "culture").
People of Italian extraction have a certain affinity for Italians, German-descendants for Germans, etc- Unless we just totally forget about Earth-That-Was I think it's reasonable to think we'd find it interesting in 1000 years.
People who speak Indo-European languages such as English, Hindi, and Portuguese descend from migrants from the Caspian steppe. Do they have strong Caspian steppe affinities? And that's only been about 4000 years.
People seem to find the Yamnaya culture interesting, we just know rather little about it.
Nowadays we have ubiquitous, effortless recording and copying capabilities. The struggle for historians will be to sort through all the data in order to identify a coherent narrative.
I expect Earth will be viewed as we view Athens now. There's a lot of important history which happened there, and schoolchildren spend a lot of time studying it, but the center of the action has moved elsewhere.
Instead of "How often do men think about ancient Rome?", people will ask: "How often do men think about ancient Earth?"
"We" is doing a lot over work over, what, five billion years? That's longer than the history of existing life. Literally unimaginable.
And when you consider that by this point energy input is on a permanent increase, there's really not much you can do apart from moving the whole damn planet out of the way.
It's kind of pointless to speculate what kind of technology we'll have in 500m years (or indeed if there is a 'we' left in the system). The time scale is so enormous that there's simply no way to predict anything at all involving humans or human-derivatives.
The planet (without literally unimaginable intervention) will heat up and become uninhabitable sometime around 500m years from now.
You can put something in between, a giant sun shade
Maybe someone smarter than me can calculate the optimal parameters to get the smallest shade that orbits the sun. If we are looking to only block out a percentage of the sun then it doesn’t even need to be fully opaque, maybe a giant dream catcher would be fine.
And already a known option for our current global warming situation.
That means you're heavily restricted in where you can put it. It has to be either right next to earth, in which case it's hard to keep away from Earth, or at L1, which is not stable. There's no other place you can put something where it will stay directly between us and the sun.
I suspect the atmosphere, ecology and albedo would adjust to radiate the extra energy away anyway.
Now I'm actually morbidly curious: do you think humans could even come close to sterilizing this planet if we wanted to? I mean maybe we could burn away the atmosphere if we set off enough nukes (probably more than humanity's ready-to-use-stockpile, I think?), but the biomass that's inside the ocean (...would that even remain without an atmosphere or would it boil off? regardless...) and crust is simply massive. I strongly suspect that life would keep on going.
That’s a really misleading way to describe what going on. The amount of energy radiated into space is a function of temperature, so increasing incoming radiation also increases outgoing radiation. 5% increase in luminosity is roughly 3.5C increase in earths average surface temperatures ignoring other effects.
However, you get a feedback loop as water vapor is a greenhouse gas which makes things hard to model. Here’s a study suggesting the tipping point is on 1 billion years https://www.sciencedaily.com/releases/2013/12/131216142310.h... but it’s not suggesting the oceans literally boil but rather a transition point where there’s a lot more water in the atmosphere.
It's a bit disappointing to think that billions of years of evolution would result in only hardy bacteria or algae surviving to represent life. I think the continuation of consciousness is a more interesting goal... whether it happens in our carbon-based biology or in some other way is a secondary concern.
Why though? Because they have little to no ability to understand the consequences of their actions?
ot: have you ever looked into what the proper nomenclature is for dog breeds? None! They have subspecies based on vibes. Species is a human construct, one that doesn't even serve us in our second most familiar of categories. It seems difficult to double down based on a "science" of naming things.
Life matters. A lot. The whole Universe is this big mechanical device that obeys to the law of causality: every change in nature is produced by some cause. For billions of years, this was all there was. Then suddenly Life happened, turning causation on it's head: Life's actions have what Aristotle called a "final cause", that never existed before. Life has at least the goal of survival, and maybe more, yet to be discovered. And this changes the nature of the Universe for the Universe now has will.
As for humans, my comment was not meant to disparage them. They are far from perfect, basically apes, and right now they are the best hope we have for Life to survive the Sun. But humans are only a transient form that Life can take. There was Life before humans, let's hope there the will be Life after them. They are no more than a cog, albeit one that may someday reveal itself to be useful.
It's totally possible that Life just dies. Like due to increased solar heat or a random comet.
Dinosaurs (and other saurs) wandered Earth for hundreds of millions of years, humans are just a blip on the radar. But dinosaurs wouldn't be able to predict Sun's death and do something about it.
A handy reference for this topic
The idea of keeping bureaucracy alive much longer than our planet is human optimism at its best. Death and taxes, come Hell, high water, and the literal evaporation of Earth's oceans due to surface temperatures exceeding 1130 C.
Fellas, is it bureaucratic to use calendars?
Huge fan btw, and thank you for the unix haters handbook.
250 million, owing to the expansion of the sun and formation of a supercontinent.
Not that I don't find that article interesting, of course. And I wouldn't underestimate our ability to (continue) to terraform the earth, intentionally sure, but much more certainly unintentionally.
Eg https://www.sciencedirect.com/science/article/abs/pii/S00319...
I mean we still put forever chemicals in our food containers. There’s a segment of the population that aggressively opposes efforts to save humanity from global warming (the earth abides but humanity is quite fragile). We’ve had at least six known near misses in nuclear annihilation. We’ve been utterly unable to stamp out obvious misinformation, lies and utter bullshit in public discourse (so we can’t even talk about the real problems with anything approaching consensus on facts)
The good news is we really don’t have to worry about the timeframes where the death of our star would cause problems.
I probably won't be around in 100 years, but I'd place the odds of human extinction in that time frame at approximately 0. 1 billion is right out though. If there are descendants, they almost certainly won't be homo sapiens.
0.1%? Probably. And that's probably the highest that number has been in millennia.
You did mention "the end of humanity in my lifetime" after all.
... Yes? Do you really, seriously think that eight billion people can so easily disappear within a couple of generations and there won't be anyone left for the population to start growing again?
This is not well-reasoned.
Climate change, even in its most hysterical worst case scenarios, could make large areas of the planet uninhabitable, and cause massive migrations, wars, and famines. But it won't kill everyone.
Forever chemicals, even if you believe they're responsible for reduced fertility, haven't sterilized humans. We're not in the Handmaid's Tale yet, and if we were, it's pretty clear there would be resulting cultural shifts to address fertility.
Nuclear annihilation is not possible with current arsenal levels. You would need millions of high yield detonations to accumulate lethal levels of radiation planet wide. Nobody has that many nukes. There's enough to make large areas uninhabitable, but it won't kill everyone. Nuclear winter could cause famines, but isolated groups can use existing technology for indoor farming.
There are some things that could kill us off entirely (asteroid), but none of the things you mentioned are going to do it.
How old are you?
https://en.wikipedia.org/wiki/Star_lifting#Stellar_husbandry
A bazillion dollars to explore new worlds, to find this mold that won't come off.
Maybe it will talk to us.
You're writing as if watery moons around gas giants aren't something we look for.
The answer is yes, of course. Everyone on Europa is going to be fine.
Humanity is a virus
Does anybody know what is the timescale we are talking about here? From start of inflation of Sun's outer atmosphere to engulfing of earth?
If the red giant phase of the Sun (before its collapse) were to be just not quite hot enough to do more than scorch the surface of the earth and maybe heat the crust down only partially, microbial life would survive in deep fissures. Studies (link below) have shown that a whole ecosystem of life exists in wet cracks down to a depth of up to maybe 10 kilometers. Assuming the red giant phase of the sun only manages to cook the earth's surface, it's possible that the heat radiates down into the crust by a few hundred meters, or maybe a kilometer.
After all, though rock as a dense object in your hand isn't a good thermal insulator, the porous, cracked substrate of our crust is indeed wonderful at insulating (second link). If it weren't we'd have long since cooked from the enormous heat beneath us. The same process works in the opposite direction.
Thus IF, if the sun expands just enough to only scorch our world, once the sun collapses again and our planet enters its deep freeze, the microbes that survived far beneath its surface could live their strange existence indefinitely, close to magmatic heat sources in the delicately balanced equilibrium zones between these and the frozen world above.
Yes, the core of the earth will also eventually cool too, but the combination of residual heat from formation, compressive friction heat and radioactive decay is enough to keep that from happening for at least tens of billions of years.
It's a fascinating scenario to consider: the extreme limits of how tenacious life could stay alive on our world long after everything we consider sustaining is dead and gone.
https://en.wikipedia.org/wiki/Deep_biosphere
https://manoa.hawaii.edu/exploringourfluidearth/physical/oce...
Is the heat produced inside a planet, mostly from the radioactive decay of natural isotopes.
Volcanoes are not powered by the Sun. Of course this production will cease when all isotopes will be depleted, but that will take a very long time.