[meteorite-list] Spurious extinction "periodicity"

[Matson, Rob D.]

It was my understanding that the 26- or 27-million-year periodicity idea was
discredited some time ago as not being statistically significant. In any case,
no “Nemesis” red- or brown-dwarf companion star (presumably in a highly
elliptical orbit) has ever been found, and if one existed within even 10 lightyears
of the sun, WISE would have found it.  --Rob