astrodynx.argument_of_periapsis

astrodynx.argument_of_periapsis#

astrodynx.argument_of_periapsis(node_vec, e_vec)[source]#

Returns the argument of periapsis of a two-body orbit.

Parameters:

  • node_vec (ArrayLike) – (…, 3) node vector of the object in the two-body system.

  • e_vec (ArrayLike) – (…, 3) eccentricity vector of the object in the two-body system, which shape broadcast-compatible with node_vec.

Return type:

Array

Returns:

The argument of periapsis of the orbit.

Notes

The argument of periapsis is calculated using equation:

\[ \omega = \arctan2(\|\boldsymbol{N}\times \boldsymbol{e}\|, \boldsymbol{N} \cdot \boldsymbol{e}) \]
where \(\omega\) is the argument of periapsis, \(\boldsymbol{N}\) is the node vector, and \(\boldsymbol{e}\) is the eccentricity vector.