# Search results

1. ### Orbiter and Earth rotation

I'm working now on tuning some celestial body rotation parameters in Orbiter, trying to make them closer to current IAU model using Python and pygmo2 optimization. For some bodies there is some space for optimization. For example Ganymede: Some rotation parameters are very close to optimal...
2. ### Rotation slowdown

Can someone explain why rotation of DG in this scenario slowdowns in Orbiter and stops after few days (at x1000)? Orbiter v111105, all realism and perturbation check-boxes switched on. Is it real physical effect or bug of the Orbiter? BEGIN_DESC Contains the latest simulation state. END_DESC...
3. ### Project Lagrange points

It's a simple addon for computing position and velocity of Lagrange points in Orbiter.
4. ### SDK Question Barycenter velocity?

How to get barycenter velocity? I need it for calculation of Lagrange points for planets. oapiGetBarycentre returns position only :(
5. ### Lagrangian points

Need help with calculation of Lagrangian points in cartesian coordinate system. Input data: Major body: positon <0,0>, speed <0,0> , mass = M1 Minor body: position <R,0>, speed <Vx,Vy> (elliptical orbit with eccentricity near 0, so Vx is not zero), mass=M2 How to calculate position and...
6. ### Question Global position in Orbiter

API_Reference.pdf: oapiGetGlobalPos() Returns the position of an object in the global reference frame. "The global reference frame is the heliocentric ecliptic system at ecliptic and equinox of J2000." Heliocentric? But Sun at J2000 (MJD 51544.5) is not in (0,0,0) if oapiGetGlobalPos() does not...
7. ### SPICE module

I'm trying to add support for SPICE ephemerides to Orbiter. First results here: SPICE ephemeris module SPICE is NASA's library for archiving data for space missions - spacecrafts, planets, satellites positions, orientations, and other data. In Orbiter it may be useful for computing...