CartesianOrbit meanToHyperbolicEccentric method failure
Apparently resolution of hyperbolic Kepler equation would fail for the following conditions:
- state vector =
[-6.7884943832E7 -2.1423006112E7 -3.1603915377E7 -4732.55 -2472.086 -3022.177]
(m,m/s); -
mu = 324858598826460
(m^3/s^2)
resulting in output hyperbolicc eccentric anomaly close to 240 rad.
This seems to be due to the initial solution chosen to start the iterative process (H=-M). By employing Danby's initial guess to start the iterative process the issue is solved:
H = FastMath.log(2.0*M/e+1.8);
For reference
Title: The solution of Kepler's equation. I
Authors: Danby, J. M. A. & Burkardt, T. M.
Journal: Celestial Mechanics (ISSN 0008-8714), vol. 31, Oct. 1983, p.
95-107.
http://adsabs.harvard.edu/full/1983CeMec..31...95D
http://www.cdeagle.com/omnum/pdf/demokep1.pdf
(from redmine: issue id 135, created on 2013-04-18, closed on 2013-04-18)
- Relations:
- relates #114 (closed)