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View Full Version : Anything interesting happeining in the next 32 to 320 billion years?



parallaxicality
2009-Jul-02, 06:27 PM
I'm working on an event timeline using seconds to the power of ten. I'm pretty set for 1017 seconds (age of the Earth, oldest known star, one kalpa), and the open universe hypothesis has already done everything for 1019+ seconds, but I'm a bit short on 1018 seconds. So far I have the Earth and the Moon becoming tidally locked at 50 billion years and the Big Crunch at 100 billion. I need one or two more to make a list. Any thoughts?

dwnielsen
2009-Jul-02, 07:19 PM
I don't know if this is valuable, but something I stumbled across while searching:

http://www.nytimes.com/2007/06/05/science/space/05essa.html?_r=2&ref=science&oref=slogin

robross
2009-Jul-02, 07:39 PM
I'm working on an event timeline using seconds to the power of ten. I'm pretty set for 1017 seconds (age of the Earth, oldest known star, one kalpa), and the open universe hypothesis has already done everything for 1019+ seconds, but I'm a bit short on 1018 seconds. So far I have the Earth and the Moon becoming tidally locked at 50 billion years and the Big Crunch at 100 billion. I need one or two more to make a list. Any thoughts?

Well at 50 Billion years the sun will be a cooling white dwarf, and the Earth/Moon system may have been sand-blasted into dust by the outer envelope of the Sun during its red giant stage. (Although some scientists now think that Earth might just barely escape this fate.) At any rate, the Earth and Moon, if still around, will be much farther out than they are now, and subject to much less gravity from the Sun, so I'm not sure how that would affect any tidal-locking that might have taken place.

Also, 100 Billion years is not that much longer than the current age of the universe (only 1 order of magnitude larger) so really, the universe will look pretty much like it does now, only a lot more spread out (much more space between large galaxy clusters), so fewer observable galaxies from our current position. Also, most of the local supergroup will have coalesced by then, merging into one giant galaxy furball of gas and dust, and there still should be a lot of small to medium sized stars burning, that were created in the last great galaxy collisions. But new star formations in our supercluster will have slowed down considerably, as there will not be a lot of free hydrogen left in large clouds from which to form new stars.

Finally, we currently think there will NOT be a Big Crunch, but even if this were to happen, it would certainly not occur in a mere 100 Billion years from now.

Rob

Ken G
2009-Jul-02, 08:54 PM
Yes, on the 100 billion year timescale, I'd tend to point to changes in galaxy evolution, and the corresponding changes in stellar evolution. Around then, I'd expect a lot less new stars to be formed, so the kinds of stars one would generally see would start to be very different-- lots of white dwarfs and low-mass stars, but less in the way of solar-like stars and few supernovae. If you do get a relative dearth of solar-like stars by then, it might start to have a very significant impact on the state of life in the universe. Barring great technological advances, or oversights about what life can do, one might point to something like 100 billion years as the twilight of the era of life.

PraedSt
2009-Jul-02, 09:09 PM
Blimey. No wonder you're in a bad mood.

I heard that a super-duper atomic clock would lose a second in a 100 bn yrs. I can't vouch for my memory.

Ilya
2009-Jul-06, 02:42 AM
All actinides in Solar System will have decayed. Bismuth will be the heaviest remaining element.

I specify "in Solar System" because stellar activity will continue, and supernovae will be still seeding the universe with heavy elements.

Fiery Phoenix
2009-Jul-06, 06:38 AM
I wouldn't say too much will change in 100 billion years. The Universe will probably remain as it basically is; the only difference is that new stars and new planets and stellar system will have born in every galaxy there is, and almost all of the stars we know today won't be there anymore by then -- including us. Some galaxies will basically "refresh" themselves and give birth to a whole new generation of stars, while others will have already run out of the material needed to form stars. And of course, the Universe will be much larger that it is now, since it's on an expansion process.

I can't think of much else, really.

parallaxicality
2009-Jul-06, 09:06 AM
All actinides in Solar System will have decayed. Bismuth will be the heaviest remaining element.

I specify "in Solar System" because stellar activity will continue, and supernovae will be still seeding the universe with heavy elements.

Thanks! That helps. Now I have three. And three is a list.

AriAstronomer
2009-Jul-09, 06:31 PM
I'm not sure exactly when this will happen (and possibly either do astronomers), but eventually when the space-time acceleration exceeds the speed of light, you won't be able to look up and view other galaxies anymore, and although to the naked eye the sky may not appear that different (as far as the number of stars in the sky go, not the arrangement of the constellations), when viewing with a telescope, anything outside our galaxy will be seen as empty black. You could probably find a general time of when this will happen.

robross
2009-Jul-09, 07:59 PM
I'm not sure exactly when this will happen (and possibly either do astronomers), but eventually when the space-time acceleration exceeds the speed of light, you won't be able to look up and view other galaxies anymore, and although to the naked eye the sky may not appear that different (as far as the number of stars in the sky go, not the arrangement of the constellations), when viewing with a telescope, anything outside our galaxy will be seen as empty black. You could probably find a general time of when this will happen.

To me, this is an example of one of the few times that the cosmological principle does not hold. In the far future, and for the majority of the age of the universe, there will be no stars burning, and nothing to "see" (worse than that- no one to see anything) once the observable universe shrinks to our local super cluster. Thus, it appears we humans *are* living in a "special" time, near the beginning of the universe, that lets us observe distant galaxies and stars.

Rob

parallaxicality
2009-Jul-09, 08:26 PM
I don't know if this is valuable, but something I stumbled across while searching:

http://www.nytimes.com/2007/06/05/science/space/05essa.html?_r=2&ref=science&oref=slogin

Sorry I didn't notice that before. Was really helpful. Thanks.

Glom
2009-Jul-14, 06:30 PM
This is all really depressing. I prefer Rosalina's version of astronomy, where stars scatters their stardust that reforms into new baby stars that actually cry like babies and the cycle repeats ad infinitum.

Glom
2009-Jul-14, 06:31 PM
the space-time acceleration exceeds the speed of light,

Would that happen? Or would it just increase asymptotically. And how can an acceleration exceed a velocity? That's like saying the current is greater than the voltage.