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Author Topic: close orbiting binary star system experiment  (Read 8325 times)

smjjames

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close orbiting binary star system experiment
« on: February 01, 2012, 01:49:19 PM »
Just a quick note, since there are problems with textures not showing properly when others download and view the save files, I didn't put any textures on.

I decided to try and see how well I would get planets orbiting a close binary system. By close, I mean orbiting in days or hours.

At first I tried to do ones that orbited in a few days to get a decent minimum simulation speed, but it just made things much harder to get into a stable orbit and when I tried an accretion mode, I kept having problems with the orbits. Not to mention the fact that it would be extremely difficult to get it set up for conversion to normal size. Doing it with an orbit of hours worked better, but I still had the same issue of the orbit indicator phasing in and out as the stars orbited each other.

SO, I decided to just go and do the bodes law method. I ended up with a seed number of 1, however I moved the first two inwards because it ended up getting all bunched together at 0.48, 0.54 and 0.84 AU. While the first seven are stable, I'm not sure if the gas giants are stable. I may have lost the outer two, but the two small ones might be stable, hard to tell.

Also, if you're looking for an Earthlike paradise, you won't find one here, unless 'paradise' is a frozen planet with an average temp around 23 F or a steaming world with an average temp around 104 F, and thats if it doesn't evolve into a Venus equivalent. Life MIGHT evolve on those worlds, but whether it might evolve beyond bacteria is an unknown.

In conclusion, Dan needs to get the orbits (or at least the orbit info) to work right with binaries.

FiahOwl

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Re: close orbiting binary star system experiment
« Reply #1 on: February 01, 2012, 02:07:09 PM »
Nice System.

Quote
In conclusion, Dan needs to get the orbits (or at least the orbit info) to work right with binaries.

smjjames

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Re: close orbiting binary star system experiment
« Reply #2 on: February 01, 2012, 02:52:19 PM »
Update: After running it for some simulation years (turned all visual effects off), I've found the first three gas giants to be in a stable orbit. However, since the last one is 134 AU out and has a thousand year orbit, it isn't possible to tell just from the trail (unless theres a very, very slight curve) whether it's stable.

Yannos

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Re: close orbiting binary star system experiment
« Reply #3 on: February 01, 2012, 03:29:24 PM »
I suppose that your best bet on creating a binary system living paradise in Ubox and in real life would be to create the binary system based on 2 stars with very small mass difference which are really close. By the way these often are tidally locked to each other.

Though still binary system equals instability for the planet. And I am not referring to simulation instability. I am referring to lack of stable real life conditions. Earth had a relatively stable orbit for an incredible amount of time and yet you can see for how small period humans inhabit it.

And make sure you are not taking the earth's temperature mentioned in Ubox as something completely correct as we can not be certain that it is calculated correctly for 2 stars, not to mention that the habitable zone is definitely not calculated correctly for 2 stars. ;)

smjjames

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Re: close orbiting binary star system experiment
« Reply #4 on: February 01, 2012, 04:03:29 PM »
True, also those two stars are a sunlike star that is slightly larger and slightly brighter than ours while the companion is a class M8 or 9 red dwarf. I'm actually not sure if the luminosity value for the red dwarf is correct.

As I observed, the further out the close binary pair is, the less stable the orbits are. If the two are in an orbit of at least a year, then there is a chance for stable orbits close in to the stars.

vh

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Re: close orbiting binary star system experiment
« Reply #5 on: February 01, 2012, 06:07:46 PM »
hmm, if you put the stars far enough apart, i wonder if you could...get a planet orbiting in figure eights? maybe even in equlibrium in the center although that probably would never happen irl.

smjjames

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Re: close orbiting binary star system experiment
« Reply #6 on: February 01, 2012, 06:18:56 PM »
hmm, if you put the stars far enough apart, i wonder if you could...get a planet orbiting in figure eights? maybe even in equlibrium in the center although that probably would never happen irl.

Temporarily, yes, I had that many times with the Alpha Centauri accretion, but they are never stable over a long period and either get knocked out or fall into a new orbit. However, a stable figure eight orbit lasting for millions or even billions of years? Such orbits are certainly extremely rare.
« Last Edit: February 01, 2012, 06:47:43 PM by smjjames »

Dan Dixon

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Re: close orbiting binary star system experiment
« Reply #7 on: February 02, 2012, 10:10:49 PM »
This is really cool. Interesting experiment.

In conclusion, Dan needs to get the orbits (or at least the orbit info) to work right with binaries.

Agreed. :)  We'll get it fixed eventually.


smjjames

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Re: close orbiting binary star system experiment
« Reply #8 on: February 03, 2012, 03:08:47 PM »
And make sure you are not taking the earth's temperature mentioned in Ubox as something completely correct as we can not be certain that it is calculated correctly for 2 stars, not to mention that the habitable zone is definitely not calculated correctly for 2 stars. ;)

Not to mention the fact that it's a simple atmosphere model. As for the temperature being calculated correctly, I checked by deleting one of the stars in the system im currently experimenting with and it does take into account more than one star. In the case of the system here, the companion star is almost a brown dwarf and is so dim that even the closest planet doesn't register any change in temperature when I delete it. So the variation is coming from the pairs wobble and the speed would make it average out.

However, I do have a few questions myself on the 100% accuracy of the temperature when one star is eclipsing the other or are in conjunction.