GLEAM-X J162759.5−523504.3

GLEAM-X J162759.5−523504.3 is a transient astronomical radio source, found in 2020, in archival data recorded in 2018 by the Murchison Widefield Array.
The source was active in radio for about 1 minute every 18 minutes, from January to March 2018, but has not been recorded since.

Nature of source

It seems somewhat like a Galactic Center radio transient except it is thought to be only about distant.
The radio emissions were polarised so it may be a predicted astrophysical object called an "ultra-long period magnetar".