Algol is well known in astrology for its malefic nature, being associated with murders and other unfortunate events, "losing one's head" (by beheading or - figuratively speaking - by the abuse of alcohol), monsters. However, every almost 3 days there is a 2 hours period when its influence is less stronger - it's the Minima of Algol !
Here's the astronomical info explaining this phenomenon:
Algol is a double, eclipsing variable star in the constellation Perseus, almost as bright as Polaris. Algol's variation in apparent brightness has a periodicity of 2 days, 20 hr and 49 min. The cause of Algol's rapid brightening and subsequent fading are well understood: Algol is actually made of TWO stars, not just one, as seen from Earth being aligned as an "eclipsing binary" star in which one star periodically occults, or covers up, the other in their tight orbit around one-another. Hence, with Algol, this system "eclipses" on a very predictable cycle; the MINIMUM BRIGHTNESS (called the "Minima of Algol") is the brightness of the two stars seen aligned toward Earth, while the MAXIMUM BRIGHTNESS results when both stars are "in full view" (even though we cannot resolve the double nature as the stars are too close)...read more...
Algol is a double, eclipsing variable star in the constellation Perseus, almost as bright as Polaris. Algol's variation in apparent brightness has a periodicity of 2 days, 20 hr and 49 min. The cause of Algol's rapid brightening and subsequent fading are well understood: Algol is actually made of TWO stars, not just one, as seen from Earth being aligned as an "eclipsing binary" star in which one star periodically occults, or covers up, the other in their tight orbit around one-another. Hence, with Algol, this system "eclipses" on a very predictable cycle; the MINIMUM BRIGHTNESS (called the "Minima of Algol") is the brightness of the two stars seen aligned toward Earth, while the MAXIMUM BRIGHTNESS results when both stars are "in full view" (even though we cannot resolve the double nature as the stars are too close)...read more...