A radio telescope in Australia has detected impulses from an object that repeat every 18 minutes. They want to call it a pulsar but realize that a pulsar spinning that slowly would give out very weak signals. The signals reported
make it one of the brightest radio objects in the sky.

These two facts fight each other at a very basic scientific level. The slowest pulsar we know of spins its radio beam our way, once every 11 seconds. The answer to the question: What is this object, really, awaits further study.

Please find a link, below, to an article with further information:

https://www.universetoday.com/154287/astronomers-discover-a-mysterious-star-that-flashes-every-20-minutes-but-what-is-it/