Alterf

λ (lambda) Leonis, a star of spectral type K5 with a magnitude of approximately 4.5. The Arabic-derived name means "the Glance of the Lion".

Alterf was formerly a yellow giant of type K1 which became dangerously unstable some tens of thousands of years ago, due to an unexpected in-system incursion by a black hole too large to be diverted. When it could not be restabilized, Alterf's inhabited planets had to be evacuated and their inhabitants and technologies eventually rafted to other solar systems across three neighboring galaxies.

The star collapsed into its present state approximately a year and a half after the rafting was completed. (AWOM)