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View Full Version : Is it possible for humans to out live our sun?



edaniel
2018-Nov-30, 04:48 AM
I have a school project and I need peoples input. I was wondering if anyone could help me answer my question.

Thanks

pzkpfw
2018-Nov-30, 06:42 AM
I have a school project and I need peoples input. I was wondering if anyone could help me answer my question.

Thanks

What are your own thoughts so far?

Jens
2018-Nov-30, 07:00 AM
I have a school project and I need peoples input. I was wondering if anyone could help me answer my question.


It might help us also if you could explain a little more about what the project entails. The reason is that normally we avoid doing people's homework for them. But if you can describe what it is exactly that your project is about, and what you have done so far, then I'm sure that people (including me) will be happy to give you feedback or alternative ideas.

edaniel
2018-Dec-03, 10:43 PM
Right now i believe that it would not be possible. The sun has approximately 5 billion years before it will turn into a red giant and destroy earth. In a billion years our oceans will start to boil and we wont be able to live on earth. I think we will have to leave before that due to pollution. Our technology in the next few thousand years may be able to help us colonize other planets in our solar system. Even if we do make it that far, we would need to find a new place to live before our sun turns into a red giant. The closest star to us would be Alpha Centauri and that would take about 80-90 thousand years with our current technology. Im not sure we would be able to survive that long in space.

Van Rijn
2018-Dec-04, 01:38 AM
I think you have a pretty good handle on the issue. It's apparently somewhat up to debate if the sun will vaporize the Earth as it expands, or leave something behind, but at best Earth certainly would be too hot to live on, even in underground habitats.

Aside from the sun itself, you might want to consider the timescales involved compared to how long species last, or how long complex life has existed. Do you think humans would continue on several billion years even if the sun weren't an issue?

On the other hand, you might also want to consider not just the possibility of living on planets but also space habitats. You might want to look up "O'Neill Habitat" and some of related space habitat ideas. Space habitats could be moved or shielded more easily than planetary habitats.

One other thought: We will need to need to get a handle on pollution and recycling in general wherever we plan to live.

DaveC426913
2018-Dec-04, 02:29 AM
Note that, whether or not we survive, we won't be 'human' (or at least Homo sapiens sapiens).
In the strictest sense of the term, whatever we are, we won't be able to interbreed with 21st century humans, so we'll be a new species.

Jens
2018-Dec-04, 04:05 AM
edaniel, I also agree that you seem to have a good grasp of the issue. Just a couple of points to think about (not really answers, but thoughts).

One, a lot depends on whether we eventually begin migrating to other solar systems. Once we have done a few, it becomes likely that we will expand further, and then the possibility of outliving the sun increases. So that seems a major key.

An interesting issue is, what do you mean by "human"? Do you mean to indicate our species? Because if you do, then after we migrate to other planets it is likely that we will eventually lose the ability to interbreed, and so at that point do you mean modern humans or any descendants that we have?

And a small issue: you brought up alpha centauri, but actually it is a trio of stars, and the largest of them is approximately the same size and age as the earth, so presumably it will burn out around the same time. There are still star forming regions in our galaxy, but many of the stars we see in the sky will actually burn out before our sun does.

DaveC426913
2018-Dec-04, 04:19 AM
... a trio of stars, and the largest of them is approximately the same size and age as the earth.
the Sun? ;)

Jens
2018-Dec-04, 04:20 AM
the Sun? ;)

Oops! :doh:

Noclevername
2018-Dec-04, 06:51 AM
Right now i believe that it would not be possible. The sun has approximately 5 billion years before it will turn into a red giant and destroy earth. In a billion years our oceans will start to boil and we wont be able to live on earth. I think we will have to leave before that due to pollution. Our technology in the next few thousand years may be able to help us colonize other planets in our solar system. Even if we do make it that far, we would need to find a new place to live before our sun turns into a red giant. The closest star to us would be Alpha Centauri and that would take about 80-90 thousand years with our current technology. Im not sure we would be able to survive that long in space.

Also, keep in mind that, in the long term, planets may not be necessary. Eventually, we may build orbital habitats capable of supporting human life.

Such a structure would need shielding against the cosmic radiation of space, and would spin to provide pseudo-gravity. See http:// https://en.m.wikipedia.org/wiki/Stanford_torus
And http:// https://en.m.wikipedia.org/wiki/O%27Neill_cylinder
Among other designs.

While such a permanent space station could not last forever, the population living in it could use materials in asteroids to build a new habitat, and move into it. So over time, we might develop thousands or millions of such space cities, whose citizens may never have set foot on a planet's surface. We can foresee a time when the population off Earth exceeds the population on Earth.

cosmocrazy
2018-Dec-04, 10:14 AM
Humans have been around for a blink of an eye compared to cosmic time scales. In addition our "technological" capabilities have been around for a blink of an eye in comparison to how long humans have been around. Assuming humans do somehow survive extinction long enough to see the sun die then its very likely that we would have already colonized much of the Milkyway galaxy by then. Its a good subject to debate but unfortunately a difficult one to answer with any real certainty. I think as already been mentioned you seem to have a grasp of the concept already.

profloater
2018-Dec-04, 11:24 AM
The five billion year red giant might be too hot to handle sooner than that, maybe two billion years, which always reminds me of my favourite joke from school days: the professor is discussing this question and says maybe two to five billion years. From the back there is a panicked scream "How Long?"
"About two to five billion years"
" Oh thank goodness, for a minute I thought you said two to five million years!"
The serious point of that joke is that we have been able to manipulate our environment for at best a few thousand years and now we are manipulating our DNA while spoiling our climate, so to worry about the sun's life is missing an important point.

Roger E. Moore
2018-Dec-04, 02:10 PM
I wonder if the main point here is that, biologically speaking, human DNA could not possibly remain unaltered for one million years, much less five billion, so no, humans will not be around then. We'll be extinct. We might have distant descendants in that far future, but we as we are now won't be there.

profloater
2018-Dec-04, 03:57 PM
well that's not a biological argument although I agree because it seems our DNA was still changing until recently when we got clever at allowing many poor survival traits to survive. Many species of animal have stayed the same for a million years. Now that we have started changing the genome deliberately we can expect that objections will be overcome by market forces. Whether that is more effective than traditional pair formation remains to be seen! Just now the worry is that we fall behind in the evolution race with pathogens.

Eclogite
2018-Dec-04, 05:45 PM
well that's not a biological argument although I agree because it seems our DNA was still changing until recently when we got clever at allowing many poor survival traits to survive. The implied increase in genetic "weaknesses" within the population is, by definition, evolution and therefore our DNA has changed, in the important sense that allele proportions are different.

profloater
2018-Dec-04, 06:09 PM
The implied increase in genetic "weaknesses" within the population is, by definition, evolution and therefore our DNA has changed, in the important sense that allele proportions are different.
Yes i think that is what i said or meant by “i agree” but in general a species can stay the same for very lon periods.

Noclevername
2018-Dec-04, 06:18 PM
And that's only counting natural evolution, not changes we'll make to ourselves. And any other sapient beings we may create. Post-humans, post-animals, AIs, mind uploads, etc.

profloater
2018-Dec-04, 07:13 PM
It will be nice if we live up to "sapiens" and not just homo multis, if we really get to be homo sapiens we might survive another millenium or so.

Noclevername
2018-Dec-05, 12:45 AM
It will be nice if we live up to "sapiens" and not just homo multis, if we really get to be homo sapiens we might survive another millenium or so.

More than that, I think. Multiple hominid species once coexisted for much longer periods. We may again someday.

DaveC426913
2018-Dec-05, 01:02 AM
More than that, I think. Multiple hominid species once coexisted for much longer periods. We may again someday.
Yes, but likely only if we get off-planet.

It's thought that only one highly intelligent species can exist in a limited area (such as a planet) without incurring genocidal warfare. Of course, there's no strong evidence for this.

Roger E. Moore
2018-Dec-05, 01:23 AM
Multiple hominid species once coexisted for much longer periods. We may again someday.

That probably worked out well, too. "Hey, Zinjanthropus! Where's your forehead? Ha ha ha ha ha ha ha!"

Noclevername
2018-Dec-05, 03:00 AM
Yes, but likely only if we get off-planet.

It's thought that only one highly intelligent species can exist in a limited area (such as a planet) without incurring genocidal warfare. Of course, there's no strong evidence for this.

It's thought by who? Homo sapes and Neanderthals lasted about 170,000 years together.

profloater
2018-Dec-05, 09:50 AM
the Sapiens population is now orders of magnitude greater than at any previous epoch and has not yet united so unfortunately the cynical observation "Peace is a period of hypocrisy between wars" is still true. The very traits of tribal unity that made us so successful are now still in our instinctive behaviour. Survival is not the same as progress. What goes up can come down.

antoniseb
2018-Dec-05, 12:17 PM
... The closest star to us would be Alpha Centauri and that would take about 80-90 thousand years with our current technology. Im not sure we would be able to survive that long in space.
I agree with the many people who say that new species will develop that won't be HSap, or that we might simply destroy ourselves and our habitat long before the Sun gets too hot for life on Earth, or replace ourselves with machine intelligence and cyborgs, BUT I'd like to focus on the trip to other potential worlds around other stars. Currently with our best technology, we could send a craft that would spend most of the trip as a cold lump with no energy left, and it would arrive in perhaps 80,000 years (maybe a bit faster, say 20,000 years, but I'm not arguing that particular point). What I am saying is that over the next few hundred years we will very likely develop technology that could speed the trip to require only a few hundred years, and potentially keep the vessel powered for the whole trip. The big question is whether anyone will feel that it is worth the expense and effort. Who knows what we'll be able to accomplish in tens of thousands of years on that front?

selden
2018-Dec-05, 08:20 PM
What I am saying is that over the next few hundred years we will very likely develop technology that could speed the trip to require only a few hundred years, and potentially keep the vessel powered for the whole trip. The big question is whether anyone will feel that it is worth the expense and effort. Who knows what we'll be able to accomplish in tens of thousands of years on that front?

In principle, at least, such a drive is possible now, it's just that the technology is very unpopular. I.e. an Orion-style nuclear pulse engine.

antoniseb
2018-Dec-05, 09:30 PM
In principle, at least, such a drive is possible now, it's just that the technology is very unpopular. I.e. an Orion-style nuclear pulse engine.
You wouldn't need an Orion-style nuclear pulse engine. You could simply use fission (or preferably fusion) for driving an electric plasma or ion drive. Either way, we understand the principals, but are a long way from actually constructing the vessel.

Noclevername
2018-Dec-06, 02:03 AM
(Principles.)

Noclevername
2018-Dec-06, 02:04 AM
the Sapiens population is now orders of magnitude greater than at any previous epoch and has not yet united so unfortunately the cynical observation "Peace is a period of hypocrisy between wars" is still true. The very traits of tribal unity that made us so successful are now still in our instinctive behaviour. Survival is not the same as progress. What goes up can come down.

Uniting is not necessary, only a lack of mass extinction.

Solfe
2018-Dec-06, 02:19 AM
"I'm planning to live forever. So far, that's working perfectly." Steven Wright

Clever wins the internet today with a sig line. :)

Noclevername
2018-Dec-06, 04:56 AM
Clever wins the internet today with a sig line. :)

:D

profloater
2018-Dec-06, 10:32 AM
I wonder if there is enough for that homework project yet? Clearly living quarters on the moon or Mars would not help so we envision an orbiting space station which grows and eventually is self sufficient enough to leave orbit and go adventuring. Normal human life depends fundamentally on solar power so to outlive the sun needs either a younger star or an alternative power source. The current model is that some stars go supernova and spread the elements required for other stars and planets to form, That process could go on longer than our sun and provide energy either directly as stars or nuclear power. The elephant in the room of that argument is what we mean or expect from humans in any comparable time frame. Will we improve ourselves? Will we live longer lives? Or will we go the other way or split up into new species? These ideas have been aired in this thread. If put as a probability question, I guess I would assign a very low probability to remaining human that long.

Noclevername
2018-Dec-06, 04:43 PM
If we stay local, the Sun will leave a pretty corpse... a White Dwarf. Those stay hot and bright for a long time. So it could be possible to re-colonize the inner system even after the death of Sol, using the White Dwarf as an energy supply.

And if we ever invent working fusion power sources, we could perhaps harvest rogue bodies and do without stars at all.

Exposed
2018-Dec-06, 06:18 PM
According to this video we can get to Alpha Centauri using current technology anywhere from 44 to 90 years:

https://www.youtube.com/watch?v=EzZGPCyrpSU

Basically carry enough nuclear weapons to detonate behind the spacecraft at a steady rate to ride the shock wave until 10% the speed of light is reached.

DaveC426913
2018-Dec-07, 01:44 AM
According to this video we can get to Alpha Centauri using current technology anywhere from 44 to 90 years:

https://www.youtube.com/watch?v=EzZGPCyrpSU

Basically carry enough nuclear weapons to detonate behind the spacecraft at a steady rate to ride the shock wave until 10% the speed of light is reached.

I didn't watch the video, but that's the essence of an Orion Drive. Basically, you fire pellets of nuclear material out the back, then use a laser to fission them. The explosion pushes on a "pusher plate" - basically a plate on a colossal spring to even out the blasts.

Robert Tulip
2018-Dec-09, 10:03 AM
On the likelihood of human descendants still being alive in billions of years, an issue with the Fermi Paradox (https://en.wikipedia.org/wiki/Fermi_paradox#It_is_the_nature_of_intelligent_life _to_destroy_itself), the apparent contradiction between the lack of evidence and high probability estimates for the existence of extraterrestrial civilizations, is that intelligence may be unstable, so planets may often achieve intelligence but then collapse. The question for humans is whether we can cross the threshold to stable global civilization, as a basis to then continue to evolve into the long term.

21st Century Schizoid Man
2018-Dec-09, 06:50 PM
We're talking billions of years in the future, many times longer than multicellular animals have existed. I think any answer to this question is necessarily highly speculative.

Currently, any person who ventures beyond the atmosphere does so at enormous cost, and requiring incredible amounts of support from the ground. Surviving beyond the extinction of our star is vastly beyond our current capabilities, but who knows what might be possible a few billion years from now. If we asked people three thousand years ago what would be possible today, I don't think their answers would be very accurate. That might be the case even if we asked people only a hundred years ago.

The typical lifespan of a mammalian species is measured in a small number of millions of years, so if people are even still around at that time, they'll have outlasted most mammalian species by a factor of a thousand or more.

eburacum45
2018-Dec-10, 10:27 PM
Two things cross my mind;

First of all, the Sun will still exist after it leaves the Main Sequence in five billion years time; first it will become a red giant, then a white dwarf, then cool down to become a hypothetical black dwarf (there are no black dwarfs anywhere in the universe yet, according to current theories).
https://en.wikipedia.org/wiki/Black_dwarf

Secondly, it seems likely to me that we will fairly soon develop the technology to record and store DNA and other biological information in data form. I think that this means that human biological details could potentially be stored in data form for an arbitrarily long time, and maybe recreated at a distant time in the future by our distant descendants. Just as some people today would love to recreate dinosaurs, maybe the (non-human) inhabitants of the distant future might decide to recreate humans as a hobby, or for entertainment purposes, or for some other reason. Could they still recreate humans at some point after the Sun has stopped shining by internal fusion? I think they probably could. A few billion years of data-storage seems unlikely, but maybe not outrageous.

But if we have to wait until the carbon/oxygen corpse of our post-Main Sequence sun cools down and/or evaporates, that would require a spectacularly efficient form of data storage over trillions of years in order to recreate anything resembling a human being.

Noclevername
2018-Dec-10, 11:18 PM
Another potential scenario, humans might someday be capable of inventing an interstellar drive able to reach a high fraction of c for long periods. If that occurs, a generation or sleeper vessel undergoing extreme time dilation could someday return from another galaxy with a current or near-term iteration of humans aboard.

publiusr
2018-Dec-11, 12:23 AM
Voyager will outlive the Sun--so there's that.

Jens
2018-Dec-11, 12:44 AM
Two things cross my mind;

First of all, the Sun will still exist after it leaves the Main Sequence in five billion years time; first it will become a red giant, then a white dwarf, then cool down to become a hypothetical black dwarf (there are no black dwarfs anywhere in the universe yet, according to current theories).


That's actually an interesting point. Part of the answer depends on what you mean by "outlive." I think the OP and everybody has assumed the meaning was "until the sun leaves the main sequence," but in reality the sun will continue to exist much much after that.

cosmocrazy
2018-Dec-11, 11:07 AM
I thought about, if advanced enough and viable maybe our descendants will have the ability to move the earth into a higher orbit.

Noclevername
2018-Dec-11, 05:17 PM
I thought about, if advanced enough and viable maybe our descendants will have the ability to move the earth into a higher orbit.

Over very long periods, yes, the gravity tug concept could move planets. But if we could maintain a project over the time needed to do so, much longer than our history or any civilization, it would mean we truly have evolved beyond human!