FA-69673 / Orbital propagation / Member archive

Orbit energy classification: Hyperbolic semi-major axis is reported as a magnitude · case 03

Hyperbolic trajectories get positive axes indistinguishable from ellipses.

Member previewVariant 3 · 3 implementations · 7 checks per implementation

Case contract

Input [r, v, mu, tol]. eps=v^2/2-mu/r. Parabolic when |eps|<=tol*mu/r, else elliptic (eps<0) or hyperbolic. a=-mu/(2 eps) (None if parabolic), escape speed sqrt(2mu/r), v_inf=sqrt(2 eps) for hyperbolic else None. Return [kind, a rounded 3, vesc rounded 6, vinf rounded 6].

Why this case matters

Orbit determination and mission planning chain many small conversions; one wrong branch or unit silently moves a spacecraft by kilometres.

One recorded failure

Sample boundary fixture

This sample comes from the broken implementation of a controlled reproducer.

Boundary fixture	Actual	Expected	Outcome
orbit energy classification [6678.0, 11.5, 398600.4418, 1e-06]	`["hyperbolic", 30964.528, 10.925987, 3.58787]`	`["hyperbolic", -30964.528, 10.925987, 3.58787]`	Failed

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