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Module lambert

Module lambert 

Source
Expand description

Lambert two-point boundary-value orbit solver (Battin’s method).

Given two position vectors and a time of flight, solve for the transfer orbit velocities at each endpoint. This is the authoritative implementation; language bindings are thin marshaling layers over it.

Algorithm 61, Vallado, Fundamentals of Astrodynamics and Applications (2022), pp. 505-510. The velocity transfer uses the Thompson (2013/2018) hodograph formulation.

§Reference constants

VALLADO_MU below is a reference-suite value, NOT the WGS84/EGM datum. It matches the Vallado worked examples and the valladopy reference suite that the unit tests validate against (VALLADO_MU = 398600.4415, not the WGS84/GM value in crate::astro::constants). It is kept local so the solver stays bit-exact with that published reference rather than drifting to a different datum. Callers needing the WGS84/GM datum must use the constants module, not this value.

Enums§

DirectionOfEnergy
Direction of energy for the Lambert transfer.
DirectionOfMotion
Direction of motion for the Lambert transfer.
LambertError
Error returned when the Lambert solver cannot produce a valid transfer.

Functions§

battin
Solve Lambert’s problem using Battin’s method.