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Re: [Orekit Users] Spacecraft Latitude and Longitude

Hi Javier,

On Wed, 2018-06-27 at 12:08 +0200, javier.montemayor.mancias@emi.fraunhofer.de wrote:
Hey guys,

Does anyone know how to get the true latitude and longitude of a

The documentation page for SpacecraftState says that the method getLv()
returns the true latitude but there's no method for the longitude. However,
the Orbit documentation has the same method but it says that it returns the
true longitude and there's no method for the latitude. Both return the same
value, I assume the documentation for getLv() in SpacecraftState is wrong.

Could you file a bug at [1] for the discrepancy in documentation for the getLv() methods? 

You could also try using a BodyShape to compute the latitude and longitude of the satellite. E.g.

SpacecraftState s = ...;
BodyShape earth = ReferenceEllipsoid.getWgs84(ecf);
GeodeticPoint lla = earth.transform(s.getPVCoordinates().getPosition(), s.getFrame(), s.getDate());

[1] https://www.orekit.org/forge/projects/orekit/issues/new

CircularOrbit does have two separate methods getLv() and getAlphaV(), for
longitude and latitude, respectively. Would it be then okay to parse the orbit
from getOrbit() into a CircularOrbit even when it might not be so?

That should be fine. CircularOrbit does not assume that e=0, but is a parameterization that behaves well when e is close to zero.

Best Regards,

Best regards,