code: def _rotate_to_greenwich(vector, greenwich_sidereal_time):
      cos_sid = np.cos(greenwich_sidereal_time)
      sin_sid = np.sin(greenwich_sidereal_time)
      rotated = Vector3D(
          x=cos_sid * vector.x + sin_sid * vector.y,
          y=-sin_sid * vector.x + cos_sid * vector.y,
          z=vector.z,
      )
      return normalize_vector(rotated)
  
imports: from collections import namedtuple
  import dask.array
  import numba
  import numpy
  from satpy.utils import get_legacy_chunk_size
label_desc: Use image node_id 16 for calling a global function with example usage: _rotate_to_greenwich(vector, greenwich_sidereal_time) and returns: normalize_vector