Eight billion years from now

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Eight billion years from now

Postby Squid Tamer » Sun Sep 20, 2009 8:08 pm UTC

I'm thinking of writing (just a personal hobby) a story that takes place a bit over 8 billion years from now. (AD 8,100,601,870)

What geological, astrological, etx. changes could be expected to occur over the next eight billion years? In the story, the sun has not changed significantly due to someone very powerful actively keeping humanity alive and more or less un-evolving, so those changes due to those can be ignored, if you wish.

I realize that the continents will be wildly different, but will the earth still have a magnetic field? Will the core have cooled down entirely?
The Andromeda-Milky way collision will have have happened a long time before, but I don't think that that would have been any serious cause for concern.

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Re: Eight billion years from now

Postby Box Boy » Sun Sep 20, 2009 8:29 pm UTC

If I were you I would try to not use any animals from now.
Think about it, eight billion years is an ample amount of time for evelytion to take place, you could make up almost any animal you want and it wouldn't seem out of place.
You also should consider the effects if climate change and de forestation over the years, will you claim humanity was able to standluse the enviornment or is the Earth a huge desert?
I'll think of some more stuff later.
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Re: Eight billion years from now

Postby Squid Tamer » Sun Sep 20, 2009 8:57 pm UTC

I don't think that deforestation would be a very serious issue, but I'll keep the animals in mind. While keeping within reason, having really weird (to us) animals around might be fun to write.

It's one of those fantasy stories where magic (and the associated things like liches) exist, and the world has been stuck in a fantasy medieval state for most of that time. (I still need to make us something explaining why they haven't progressed. :wink: )
For very nearly the entire eight billion years, one single person has been ruling over the world. He's built up a quite amazing amount of power, and he had just enough to stop the sun from doing the unpleasant things that stars do when they get old.

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Re: Eight billion years from now

Postby Brooklynxman » Sun Sep 20, 2009 9:06 pm UTC

The Earth is one big city and all food is grown on the moon and mars
We figure out what all this means, then do something large and violent

The thing about changing the world...once you do it the world's all different.

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Re: Eight billion years from now

Postby Box Boy » Sun Sep 20, 2009 9:07 pm UTC

Squid Tamer wrote:It's one of those fantasy stories where magic (and the associated things like liches) exist, and the world has been stuck in a fantasy medieval state for most of that time. (I still need to make us something explaining why they haven't progressed. :wink: )
I'd go with something similar to FF-X then, everytime a city or society gets too advanced a monster destroys it.
You could even feature a cult which worships it and lives like they are in the stone age.
Also, since this is fantasy world that has magic (unless the people are allowed technology which seems like magic, which defeats the purpose of the medievel setting) and not based on science, shouldn't it be over in this forum?


EDIT:
Brooklynxman wrote:The Earth is one big city and all food is grown on the moon and mars

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Re: Eight billion years from now

Postby Dibley » Sun Sep 20, 2009 9:09 pm UTC

You said he has been stabilizing human evolution? Keep in mind that life has only been around for four billion years,and multicellular life for about 1.5 billion. In 8 billion years there will probably not be anything recognizably similar to life as we know it now.

The full planet city thing is not even remotely feasible, leaving aside that the moon doesn't have an atmosphere, transport costs would be ridiculous. There's absolutely no reason to try to separate the city and the farm like that. That and, as OP said, it's fantasy medieval, not star wars.

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Re: Eight billion years from now

Postby Box Boy » Sun Sep 20, 2009 9:16 pm UTC

I was joking about the moon thing.....
And also, since this is a fantasy setting and we're talking about a creature capable of commanding the stars themselves to live longer, I think it is quite possible for human evolution to have been stabalised.
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Re: Eight billion years from now

Postby Hooch » Sun Sep 20, 2009 9:31 pm UTC

The fact that the sun will explode roughly 5 billion years from now should be incorporated somehow.
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Re: Eight billion years from now

Postby Box Boy » Sun Sep 20, 2009 9:32 pm UTC

Hooch wrote:The fact that the sun will explode roughly 5 billion years from now should be incorporated somehow.

Squid Tamer wrote: In the story, the sun has not changed significantly due to someone very powerful actively keeping humanity alive and more or less un-evolving, so those changes due to those can be ignored,
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Re: Eight billion years from now

Postby Hooch » Sun Sep 20, 2009 10:35 pm UTC

Box Boy wrote:
Hooch wrote:The fact that the sun will explode roughly 5 billion years from now should be incorporated somehow.

Squid Tamer wrote: In the story, the sun has not changed significantly due to someone very powerful actively keeping humanity alive and more or less un-evolving, so those changes due to those can be ignored,


Just keeping you guys on your toes.

On a related note, what is the demonym for followers of Randall Munroe?
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Re: Eight billion years from now

Postby EdgarJPublius » Sun Sep 20, 2009 10:37 pm UTC

8 billion years is twice as long as the planet has been around to date, nothing will be recognizable, you might as well set it on a completely different planet since there will be nothing left to tie the planet that exists eight billion years from now to the one we live on now.

Pangaea ultima will have formed and broken up again and then formed again, and maybe broken up again by then, coupled with numerous impact events and super-volcano eruptions and what not,t he surface of the earth will be completely unrecognizable.

The day will be roughly 60 hours long, and the Lunar month will be roughly 50 days. The moon will appear 25-50% smaller due to it being farther away, and the Earth-Moon System will be locked (just as how now, only one face of the moon ever faces the earth, eventually, only one face of the earth will ever face the moon)

In the last five hundred million years or so, there have been five recognized 'Major Extinction Level Events', roughly fifteen-twenty other 'Extinction Events' and countless other devastating events.

If this this time-density of events remains roughly constant, over the next eight billion years we can look forward to roughly a hundred Major and 250 minor extinction events, caused by asteroids, comets, environmental changes, super-volcanoes etc.

But that's not all! As the universe ages, the stars age with it, unless all nearby stars are magically preserved like the sun, they will begin to die. the death of a star is a pretty violent event, and while most stars are either too far away, or too low mass to do much damage to the Earth, there are enough stars in the galaxy that even the low percentage prone to go supernova and near enough to do us harm encompasses a large enough number of stars that the chances of getting hit fatally is pretty much a certainty.

And even if a nearby supernova doesn't do us in, a Cosmic Ray Burst could cause an extinction even from the other side of the galaxy, and like supernovae, the chances of getting hit go up with time, after eight billion years, it's almost a certainty.

In three billion years or so, the Andromeda galaxy will slam into the Milkyway. This will not be a good thing for Earth.

There are four basic possibilities for how this will play out for us.
1. the least likely is that the Sun will be forced closer to the galactic center. The higher density of stars will basically multiply the danger of supernova and CRBs, and eventually we'll be dangerously close to the Galactic Center, which is of course a super-massive black hole. not a pleasant fate.
2. The second least likely possibility is that we will actually be abducted by the Andromeda galaxy. This is very cool idea, but as we will see, only buy's us a bit of extra time.
3. There is about a 10% chance that the sun will be pushed out of the galaxy. This is a very cool idea, and is probably the safest thing that could happen.
4. the most likely event is that not much will happen... at first anyway. As the two galaxies collide, so will the numerous and massive gas clouds within those galaxies. While most of the star forming matter int he milkyway will have been exhausted by this point, the collision will bring enough together int he form of these galactic gas clouds to spark a new generation of stars, additionally, enough extra mass will be fed into the Super Massive Black Hole at the center of both Galaxies that they will become active again. If the Sun had been ejected from the galaxy, then this would mean lots of pretty lights as the galaxies light up spectacularly. If we're a bit closer in though, then five billion years from now, the Solar system will be fried crispy. This is roughly the same eventual fate as #2

The only safe place to be will be outside the galaxy, though when the super massive black hole at the center of a galaxy goes off, it goes off big, even if we're ejected fromt he galaxy, a stray burst could still cause an extinction event.

Sources:
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This cool FAQ from NASA: http://helios.gsfc.nasa.gov/qa_earth.html
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Re: Eight billion years from now

Postby Josephine » Sun Sep 20, 2009 10:40 pm UTC

Hooch wrote:On a related note, what is the demonym for followers of Randall Munroe?

xkcdians is commonly used. I don't know about something specific to Randall, though.
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Re: Eight billion years from now

Postby chocolate.razorblades » Mon Sep 21, 2009 12:30 am UTC

How are the sun and human evolution being frozen in time? (I'd like to read this. :D)

nbonaparte1 wrote:
Hooch wrote:On a related note, what is the demonym for followers of Randall Munroe?

xkcdians is commonly used. I don't know about something specific to Randall, though.


xkcdians should be sufficient. Randall *is* xkcd.

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Re: Eight billion years from now

Postby thoughtfully » Mon Sep 21, 2009 12:39 am UTC

A couple nit-picky points..
Hooch wrote:The fact that the sun will explode roughly 5 billion years from now should be incorporated somehow.

In five billion years, the sun will become a red giant, and continue existing for some time. I can't find a reference now, but I believe its at least a few hundred million years. A red giant sheds its outer layers eventually and forms a planetary nebula, with a white dwarf at the center. It resembles an explosion in that the bulk of the star (at least by volume) is cast off, but it isn't done in a particularly violent manner, or even all at once, and nobody would mistake it for a supernova event.
http://en.wikipedia.org/wiki/Stellar_ev ... ized_stars
EdgarJPublius wrote:But that's not all! As the universe ages, the stars age with it, unless all nearby stars are magically preserved like the sun, they will begin to die. the death of a star is a pretty violent event, and while most stars are either too far away, or too low mass to do much damage to the Earth, there are enough stars in the galaxy that even the low percentage prone to go supernova and near enough to do us harm encompasses a large enough number of stars that the chances of getting hit fatally is pretty much a certainty.

And even if a nearby supernova doesn't do us in, a Cosmic Ray Burst could cause an extinction even from the other side of the galaxy, and like supernovae, the chances of getting hit go up with time, after eight billion years, it's almost a certainty.

The more common type of GRB is the long duration type, and consensus is pretty firm that these actaully are supernovae. There is less agreement about short-duration bursts, but the leading contender is a merger of two neutron stars.
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Re: Eight billion years from now

Postby Squid Tamer » Mon Sep 21, 2009 1:55 am UTC

chocolate.razorblades wrote:How are the sun and human evolution being frozen in time? (I'd like to read this. :D)


Humans are kept more or less the same by slow selective breeding. If, say, being taller was becoming a desirable trait (i.e, people found it attractive), this ruler (or more likely one of his similarly long living subordinates) would, through various means, ensure that being short is the new desirable trait. The whole system is unstable and some amount of drift is inevitable. (Someone tell me why this won't work, because I know it won't.)

As for the sun, the whole thing is a Handwave for the most part. The sun isn't frozen in time, as much as periodically "reset". I still need to think of what physical loophole he used to do that, because he wouldn't have had enough power. (Just for the record, this is not my normal thinking pattern. I usually come up with the causes first, and effects just sort of come into place naturally. As you can see, this "experiment" of not doing that has caused me to come here begging for help. :) )

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Re: Eight billion years from now

Postby Charlie! » Mon Sep 21, 2009 3:24 am UTC

Squid Tamer wrote:
chocolate.razorblades wrote:How are the sun and human evolution being frozen in time? (I'd like to read this. :D)


Humans are kept more or less the same by slow selective breeding. If, say, being taller was becoming a desirable trait (i.e, people found it attractive), this ruler (or more likely one of his similarly long living subordinates) would, through various means, ensure that being short is the new desirable trait. The whole system is unstable and some amount of drift is inevitable. (Someone tell me why this won't work, because I know it won't.)

As for the sun, the whole thing is a Handwave for the most part. The sun isn't frozen in time, as much as periodically "reset". I still need to think of what physical loophole he used to do that, because he wouldn't have had enough power. (Just for the record, this is not my normal thinking pattern. I usually come up with the causes first, and effects just sort of come into place naturally. As you can see, this "experiment" of not doing that has caused me to come here begging for help. :) )

Nuclear-level application of a custom conservation-violating teleportation spell to split heavy nuclei back into light ones?

Siphoning energy from nearby stars?

As for the genetic changes, the problem is that lots and lots of traits go into reproductive success, and not all are obvious. Subtle psychological stuff. Immune system. Genetic diseases. Sexual selection e.g. most body image stuff can be dealt with via mind control, but the actual you-survived selection requires more direct genetic fiddling to prevent evolution over such a huge timescale.

Viruses, bacteria, and other parasites should also get this evolution-b-gone treatment, otherwise we'll have our butts kicked by super-awesome diseases
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Re: Eight billion years from now

Postby EdgarJPublius » Mon Sep 21, 2009 3:54 am UTC

thoughtfully wrote:A couple nit-picky points..
Hooch wrote:The fact that the sun will explode roughly 5 billion years from now should be incorporated somehow.

In five billion years, the sun will become a red giant, and continue existing for some time. I can't find a reference now, but I believe its at least a few hundred million years. A red giant sheds its outer layers eventually and forms a planetary nebula, with a white dwarf at the center. It resembles an explosion in that the bulk of the star (at least by volume) is cast off, but it isn't done in a particularly violent manner, or even all at once, and nobody would mistake it for a supernova event.
http://en.wikipedia.org/wiki/Stellar_ev ... ized_stars
EdgarJPublius wrote:But that's not all! As the universe ages, the stars age with it, unless all nearby stars are magically preserved like the sun, they will begin to die. the death of a star is a pretty violent event, and while most stars are either too far away, or too low mass to do much damage to the Earth, there are enough stars in the galaxy that even the low percentage prone to go supernova and near enough to do us harm encompasses a large enough number of stars that the chances of getting hit fatally is pretty much a certainty.

And even if a nearby supernova doesn't do us in, a Cosmic Ray Burst could cause an extinction even from the other side of the galaxy, and like supernovae, the chances of getting hit go up with time, after eight billion years, it's almost a certainty.

The more common type of GRB is the long duration type, and consensus is pretty firm that these actaully are supernovae. There is less agreement about short-duration bursts, but the leading contender is a merger of two neutron stars.


Yea, but not all supernovae spawn GRBs, and a super-nova has other ways to kill, any supernova in our local neighborhood is bad news, but a GRB can be tens of thousands of lightyears away, or more (a GRB in 2008 was visible to the naked eye, and is estimated to have been eight billion light years away), and as long as it's pointed our way, it's bad news. (as an interesting side note, a supernova event that spawns a GRB is called a 'hypernova')

Additionally, from what I've read of short duration bursts they can also potentially be caused by solar mass black holes, neutron stars orbiting other, non-neutron stars, magnetars or a number of other sources.

There's also some evidence that the Ordovician Extinction Event was caused by a GRB.
The Ordovician Extinction was one of the Big Five, in fact, it is regarded as the second largest extinction event in the Earth's history, trailing only the Permian Extinction.

Some experts believe that a dangerously 'close' GRB could occur twice every billion years
Currently, I believe only Eta Carinae is considered a potentially dangerous GRB (if you are unfamiliar with this star, it's pretty scary, in the 1800's it has a mass-expulsion that was on par with a supernova, at 7500 lightyears away, it is the most distant object that can be seen with the naked eye, and at that it is not remarkably dim!) Luckily, the mass expulsion int he 1800's gave us a pretty good idea of where, metaphorically, Eta Carinae is aimed, and it isn't towards us. On the other hand, high-mass stars vulnerable to super- and hyper-novae are relatively short lived, in eight billion years, several generations of such stars could be born and die, over that time period, the star that kills us might not even exist yet except as a stellar gas cloud.
However, Neutron Stars and Black Holes are by their nature not easy to spot, if a set is aimed at us, we may not know until it goes off (which will be too late).


As for human evolution over this time period:

Remember that random Genetic mutations also play a role in evolution, over eight billion years even if natural selection has been bootstrapped out of the picture, genetic mutations would likely be enough to cause noticeable changes.
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Re: Eight billion years from now

Postby Omegaton » Mon Sep 21, 2009 4:35 am UTC

Squid Tamer wrote:Humans are kept more or less the same by slow selective breeding. If, say, being taller was becoming a desirable trait (i.e, people found it attractive), this ruler (or more likely one of his similarly long living subordinates) would, through various means, ensure that being short is the new desirable trait. The whole system is unstable and some amount of drift is inevitable. (Someone tell me why this won't work, because I know it won't.)

There's a South Park episode about future people where all people were all the same. This is a likely outcome of fixation and loss of alleles to to fixation, not just increased homogenization between races. 8 billion years is long enough that I think alleles will be primarily to fixation or loss due to random drift alone, which theoretically happens after infinite time... You would need selection to counteract random drift over that amount of time. The system of trying to keep the entire human species diverse is problematic as it is quite complex when you have more than two different poles to worry about. And then you have to consider the entire genome of variations, to keep it all allele frequencies the same is inherently impossible with a finite number of people.

At least, that's how I see it this late at night.

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Re: Eight billion years from now

Postby doogly » Mon Sep 21, 2009 5:21 am UTC

Squid Tamer wrote:As for the sun, the whole thing is a Handwave for the most part. The sun isn't frozen in time, as much as periodically "reset". I still need to think of what physical loophole he used to do that, because he wouldn't have had enough power. (Just for the record, this is not my normal thinking pattern. I usually come up with the causes first, and effects just sort of come into place naturally. As you can see, this "experiment" of not doing that has caused me to come here begging for help. :) )

It seems like the whole thing you want here is best done as a Handwave. If you want some really big magic in your setting, just let it be magic.
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Re: Eight billion years from now

Postby frezik » Mon Sep 21, 2009 8:58 pm UTC

Squid Tamer wrote:
chocolate.razorblades wrote:How are the sun and human evolution being frozen in time? (I'd like to read this. :D)


Humans are kept more or less the same by slow selective breeding. If, say, being taller was becoming a desirable trait (i.e, people found it attractive), this ruler (or more likely one of his similarly long living subordinates) would, through various means, ensure that being short is the new desirable trait. The whole system is unstable and some amount of drift is inevitable. (Someone tell me why this won't work, because I know it won't.)


Have you read Jurassic Park? In the book (and touched on somewhat by the movies), the attempts to control dinosaur breeding fail due to chaotic events that could not have been foreseen. "Nature will find a way".

The Metamorphosis of Prime Intellect also seems relevant, where a benevolent AI tries to act as an overseer for all of humanity.
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Re: Eight billion years from now

Postby Box Boy » Mon Sep 21, 2009 9:19 pm UTC

frezik wrote:Have you read Jurassic Park? In the book (and touched on somewhat by the movies), the attempts to control dinosaur breeding fail due to chaotic events that could not have been foreseen. "Nature will find a way".

However in this setting we must suspend disbelef and just accept the fact that this was done someow.
So can we move on from that aspect (unless you have a way to explain how it happened) and start talking about the climate and geography or something else?
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Re: Eight billion years from now

Postby thoughtfully » Mon Sep 21, 2009 9:58 pm UTC

frezik wrote:The Metamorphosis of Prime Intellect also seems relevant, where a benevolent AI tries to act as an overseer for all of humanity.

I didn't realize the relevance to the thread until you mentioned this, but the Homecoming Saga has basically the same premise.
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Re: Eight billion years from now

Postby Arete » Mon Sep 21, 2009 9:59 pm UTC

Small question:

Why are you bothering to place a story 8 billion years into the future, if you're essentially 'hand waving' all that 8 billion years might do away? Small things like the night sky being empty, most of the gas giants ceasing to function properly and so on?

Pick 200. Or 20,000. Or some less than immense[ly] arbitrary number that might allow your story to function.

?


[edit]

Rang a bell. Jack Vance!

http://en.wikipedia.org/wiki/Dying_Earth_(subgenre)


Better yet, some Byron (and someone explain how his science was so spot on in the 19th century, please!)

http://quotations.about.com/cs/poemlyrics/a/Darkness.htm

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Re: Eight billion years from now

Postby Oort » Tue Sep 22, 2009 3:39 am UTC

Tidal forces from the moon and sun will slow down the Earth's rotation. We lose a fraction of a second every year. Meanwhile, the moon is moving farther by and inch or two every year. After a couple billion i think it's supposed to fly off.

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Re: Eight billion years from now

Postby EdgarJPublius » Tue Sep 22, 2009 6:04 am UTC

Oort wrote:Tidal forces from the moon and sun will slow down the Earth's rotation. We lose a fraction of a second every year. Meanwhile, the moon is moving farther by and inch or two every year. After a couple billion i think it's supposed to fly off.

nope, I already did the math/found smart people who did the math already and posted it on the internet (see link in my earlier post)
After 8 billion years, the day willbe more than sixty hours long, and the Moon will be 50% farther away than it is now. The Earth Moon system will be locked (I.E. the same face of the earth is always direced towards the moon, the same face of the moon is always directed towards the earth)

Apparently, the current model indicates the moon won't actually fly off, though an impact on the moon, or a near pass by a large enough object could cause enough of a perturbation to send the moon off course (I dunno how big an object is required in either case, so I dunno how likely that is. probably it would take a very large object and is thus not very likely at all.)
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Re: Eight billion years from now

Postby Goldstein » Tue Sep 22, 2009 12:39 pm UTC

EdgarJPublius wrote:The day will be roughly 60 hours long, and the Lunar month will be roughly 50 days. The moon will appear 25-50% smaller due to it being farther away, and the Earth-Moon System will be locked (just as how now, only one face of the moon ever faces the earth, eventually, only one face of the earth will ever face the moon)

Okay, this is driving me crazy. If the system is 'locked' then doesn't the lunar month have to be of the same duration as the Earth day?
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Re: Eight billion years from now

Postby Tass » Tue Sep 22, 2009 1:22 pm UTC

Goldstein wrote:
EdgarJPublius wrote:The day will be roughly 60 hours long, and the Lunar month will be roughly 50 days. The moon will appear 25-50% smaller due to it being farther away, and the Earth-Moon System will be locked (just as how now, only one face of the moon ever faces the earth, eventually, only one face of the earth will ever face the moon)

Okay, this is driving me crazy. If the system is 'locked' then doesn't the lunar month have to be of the same duration as the Earth day?


Yeah, I was about to post something along the same lines

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Re: Eight billion years from now

Postby meat.paste » Tue Sep 22, 2009 2:45 pm UTC

The difference between the lunar month and the solar day could have something to do with the relative motion around the sun. The solar day is not the time it takes to complete one rotation of the earth, but is the time it takes for the sun to be in the same spot in the sky. It's sidereal versus solar days.
Huh? What?

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Re: Eight billion years from now

Postby Goldstein » Tue Sep 22, 2009 3:58 pm UTC

I don't think that explains it.

Assuming a Lunar month is the time taken for the moon to complete one full rotation of Earth, independently of the rotation of the Earth - Which must be the case if the Earth-Moon system is locked, as the only other way to look at it means there no longer are any months - then we're saying that, in this locked system, the Earth rotates once on its axis in 50 days = 1200 hours.

We're also saying that after factoring in the Earth's orbit of the Sun, the Earth appears to rotate once with respect to the Sun's position every 60 hours (This is the 'day').

So in 1200 hours the Earth rotates once on its own axis and the Sun passes overhead 1200/60 = 20 times. One of those 20 times is made up from the rotation of the Earth, and the other 19 would have to be from the Earth's orbit around the Sun. This gives us an Earth year of ~60 hours.
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Re: Eight billion years from now

Postby EdgarJPublius » Tue Sep 22, 2009 5:01 pm UTC

I'm actually not sure how it would work, it's been bothering me as well. Take it up with the people here: http://helios.gsfc.nasa.gov/qa_earth.html
since that's where the numbers came from.

I suspect though that it may have something to do with the fact that the moon doesn't revolve around the earth in the same plane as the earth rotates around it's axis. So even though the Moon and Earth may show the same face to each other all the time, the moon's orbital track might still take longer than the Earth's day.
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Re: Eight billion years from now

Postby Atre » Tue Sep 22, 2009 5:02 pm UTC

EdgarJPublius wrote:8 billion years is twice as long as the planet has been around to date, nothing will be recognizable,
.....
Sources:
Wikipedia
This cool FAQ from NASA: http://helios.gsfc.nasa.gov/qa_earth.html
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This post is full of win, pretty much nails everything.

My one addition is considering the Earth's magnetic field. You are likely to have had a LOT of polarity switches by then (which are probably bad news, we think that during a polarity switch the earth has a pathetically weak magnetic field for some indeterminate length of time... Which means that earth gets a moderate toasting from cosmic rays). You can try having a reversed N/S pole for flavour, but might not be much significance after all the continents have been doing the okey-kokey/Wilson cycle multiple times over


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