I tried to evaluate acceleration from Sun for near Earth spacecraft: R = (6700000,0,0)
with ThirdBodyAttraction acceleration method.
2021-06-21T00:00:00.000Z Sun (Earth center) : dist=152024810852 dir=(0.007511,0.917474,0.397724) Sun (spacecraft ) : dist=152024760676 dir=(0.007467,0.917475,0.397724) acceleration : a=2.53093e-07 dir=(-0.999748,0.0206110,0.00893484)
Sun direction for June 21 is correct (X component ~ 0, Z component is ~ sin(23) )
I expected acceleration to be in the same direction.
But it is in -X direction.
I’ve analised the source of ThirdBodyAttraction acceleration and found that acceleration is linear combination of two vectors. One of them is Sun-Sat and second to Sun-Earth.
Yes. I think my question is closed.