[Alas Babylon!]

It is Nemesis!

Nemesis is a hypothetical red dwarf or brown dwarf, originally postulated in 1984 to be orbiting the Sun at a distance of about 95,000 AU (1.5 light-years), somewhat beyond the Oort cloud, to explain a perceived cycle of mass extinctions in the geological record, which seem to occur more often at intervals of 26 million years.

https://en.wikipedia.org/wiki/Nemesis_(hypothetical_star)

[SunkenCiv]

Thanks all.

Here’s a scientist’s website, he’s an advocate of the Nemesis model:

http://muller.lbl.gov/homepage.html#nemesis
http://muller.lbl.gov/
http://muller.lbl.gov/pages/nemch1.htm (thanks ForGod’sSake)

John Matese has written about comet focussing (that long-period comets are disproportionately arriving from the same point in the outer solar system):

http://www.ucs.louisiana.edu/~jjm9638/matese.html