Algol, a triple star located in the constellation Perseus, is known as “the blinking eye of the Gorgon Medusa” because of its regular brightness variation.
Visible in the northeastern sky from 9 PM during the autumn months, Algol is part of a binary system where two stars orbit each other, causing a brightness drop of about 1.3 magnitudes every three days.
This variation, observed by NASA’s TESS satellite, corresponds to the mutual eclipse phenomenon between these two stars, giving the impression that the star “blinks.”
To locate Algol, observers can use the constellations Cassiopeia and Andromeda, using the star Almach as a reference point.