How do I get hyperbolic orbits to work?

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PlutonianEmpire M
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How do I get hyperbolic orbits to work?

Post #1by PlutonianEmpire » 08.07.2012, 07:55

I'm building an object that is on a hyberbolic orbit around the sun, but when I reverse the time to before the epoch, the object vanishes, and teleports itself to the edge of the universe and traverses the edge at an impossibly FTL speed.

This is the orbit definition I gave it:

Code: Select all

   EllipticalOrbit {
      Period            1.1726328762902517727583846680356
      SemiMajorAxis     -1.1120
      Eccentricity      2.7309
      Inclination       1.3247
      AscendingNode     233.5465
      ArgOfPericenter   129.3212
      MeanAnomaly       245.4497
      Epoch "1934 05 06 12:51:52"
   }


How do I get the object to work correctly?
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selden
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Re: How do I get hyperbolic orbits to work?

Post #2by selden » 08.07.2012, 14:03

PlutonianEmpire,

In my notes about orbital parameters (see http://www.lepp.cornell.edu/~seb/celest ... eters.html ) there are some formulas which might help. For example, the entry for "mean motion" includes a formula which shows how to derive the period from the eccentricity when an hyperbolic orbit is involved.


(I have deleted irrelevant posts from this thread. If you don't want to help, don't post anything.)
Selden

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Re: How do I get hyperbolic orbits to work?

Post #3by PlutonianEmpire » 09.07.2012, 00:39

How do I punch the hyperbola mean motion in into windows 7 calculator?
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selden
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Re: How do I get hyperbolic orbits to work?

Post #4by selden » 09.07.2012, 10:57

Sorry, I didn't mean to imply that you should use mean motion itself, but that some of the information there could be of use. In particular,
a = q/(1-e)
a is the length of the semimajor axis
q is the pericenter distance
e is the eccentricity of the orbit

(I've clarified some of the wording in the description.)
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Re: How do I get hyperbolic orbits to work?

Post #5by PlutonianEmpire » 10.07.2012, 00:40

I used that, and also the formulas for the period, but it's still not working for me. The object still teleports to the edge of the universe when going backwards beyond the epoch time.

I've given up on trying to fix this myself. :evil:

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Re: How do I get hyperbolic orbits to work?

Post #6by PlutonianEmpire » 29.09.2012, 04:33

The comet Ison thread made me remember this addon, and I tried setting the MeanAnomaly to 0.0, but no luck. :(

Has anyone tried figuring out the addon I made in THIS thread?
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