INNER CODE UNIT · Python
r
ATTron/astroz · bindings/python/astroz/__init__.py:151
r = np.sqrt(x * x + y * y)
lat = np.arctan2(z, r * (1.0 - _WGS84_E2))
for _ in range(10):
sin_lat = np.sin(lat)
n = _WGS84_A / np.sqrt(1.0 - _WGS84_E2 * sin_lat * sin_lat)
lat = np.arctan2(z + _WGS84_E2 * n * sin_lat, r)
sin_lat = np.sin(lat)
n = _WGS84_A / np.sqrt(1.0 - _WGS84_E2 * sin_lat * sin_lat)
p[..., 0] = np.degrees(lat)
p[..., 1] = np.degrees(lon)
p[..., 2] = r / np.cos(lat) - n
class Constellation:
"""Satellites parsed once, for repeated ``propagate`` / ``screen`` calls.
Near-earth satellites run through SIMD SGP4 batches and deep-space ones
through SDP4; a constellation can mix both.