Planets around barycenters

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thefallenghost
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Planets around barycenters

Post #1by thefallenghost » 07.03.2010, 00:47

How can I make a planet orbit a stellar barycenter (DP Leo to be more specific)? Please help!

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Hungry4info
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Re: Planets around barycenters

Post #2by Hungry4info » 07.03.2010, 08:41

If you have the barycentre defined in the .stc file, then you'll see it has a name.

DP Leo A is told to orbit DP Leo
DP Leo B is told to orbit DP Leo

Code: Select all

OrbitBarycenter "DP Leo"
<--- that's the barycentre's name.

In the .ssc file, just define the planet as orbiting around that barycentre.

Code: Select all

"b" "DP Leo"
{
 ... code
}


This will make a planet b in orbit of the DP Leo barycentre.

Unless they've fixed it by now, the temperature of the planet will always be 0 K, since it is not orbiting a star anymore. This comes from a limitation where Celestia does not incorporate the heating from stars that the planet is not orbiting (as defined by the .ssc file, the planet is not orbiting any stars, but a barycentre).
Current Setup:
Windows 7 64 bit. Celestia 1.6.0.
AMD Athlon Processor, 1.6 Ghz, 3 Gb RAM
ATI Radeon HD 3200 Graphics

ajtribick
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Re: Planets around barycenters

Post #3by ajtribick » 07.03.2010, 12:23

Note that the DP Leo system is incorporated in the latest version of extrasolar.ssc/extrasolar.stc which can be downloaded from the Subversion repository. Here's a link to the data directory of the repository.

Hungry4info wrote:Unless they've fixed it by now, the temperature of the planet will always be 0 K, since it is not orbiting a star anymore. This comes from a limitation where Celestia does not incorporate the heating from stars that the planet is not orbiting (as defined by the .ssc file, the planet is not orbiting any stars, but a barycentre).
It is "fixed" in the latest SVN versions by removing temperature display for planets. There were several issues with the numbers that were being displayed, as a result it was decided it was better not to display anything.

Topic author
thefallenghost
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Re: Planets around barycenters

Post #4by thefallenghost » 07.03.2010, 17:20

Thanks! I just realized I had simply forgotten to close my bracket in the ssc file.

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Hungry4info
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Re: Planets around barycenters

Post #5by Hungry4info » 07.03.2010, 21:39

ajtribick wrote:It is "fixed" in the latest SVN versions by removing temperature display for planets. There were several issues with the numbers that were being displayed, as a result it was decided it was better not to display anything.
Ehh fudge. Now I'm going to actually have to do math to find out if a planet is in the habitable zone or not. :lol:
Current Setup:
Windows 7 64 bit. Celestia 1.6.0.
AMD Athlon Processor, 1.6 Ghz, 3 Gb RAM
ATI Radeon HD 3200 Graphics

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PlutonianEmpire M
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Re: Planets around barycenters

Post #6by PlutonianEmpire » 13.03.2010, 04:34

Hungry4info wrote:
ajtribick wrote:It is "fixed" in the latest SVN versions by removing temperature display for planets. There were several issues with the numbers that were being displayed, as a result it was decided it was better not to display anything.
Ehh fudge. Now I'm going to actually have to do math to find out if a planet is in the habitable zone or not. :lol:
One thing I've noticed, is that for planets in the habitable zone, the apparent magnitude of the parent star is almost always around -26.6 to -26.9. So that should be helpful in determining habitable zones. :)

EDIT: Actually, I found two online calculators that can help you. The first is an archived version of that "Plan a planet orbiting a main sequence star" page:

http://web.archive.org/web/200111182136 ... eqstar.htm

The other is a stellar luminosity calculator:

http://www.calctool.org/CALC/phys/astro ... _magnitude

Using these together may be quite useful. :)

A general rule of thumb is for a planet orbiting a close binary, assume that the star is twice as massive and twice as bright as the original.
Terraformed Pluto: Now with New Horizons maps! :D


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