Caveat Emptor: Spurious Spin Vectors from Incorrect Sidereal Periods

Spin vector and shape solutions are among the most sophisticated and nuanced analyses that might be undertaken by lightcurve observers who compile measurements from multiple apparitions. Unambiguously determining the correct sidereal period before attempting convex inversion is key, because an incorrect period leads naturally to a spurious spin vector solution. A specific case study for (1443) Ruppina is examined here, with advice on how to recognize an incorrect sidereal period and avoid proceeding with a convex inversion analysis that will be spurious.