Why did our ancestors come to see Algol as the Demon Star? EarthSky’s Will Triggs explains in this video. Watch above or on YouTube. Get ready to meet the scariest star in the sky! Its name is Algol, ...

Arguably, a hobby’s greatest benefit is derived from its rewards. I’ve been an avid backyard astronomer for 60 years. I still recall the night in 1963 when my high school friend Ray Gerbi showed me ...

Ancient Egyptian astronomers may have discovered variable stars, and calculated the period of a well-known one called Algol, thousands of years before Europeans. But they buried those observations in ...

The Ancient Egyptian papyrus Cairo 86637 calendar is the oldest preserved historical document of naked eye observations of a variable star, the eclipsing binary Algol - a manifestation of Horus, a god ...

The Ancient Egyptians were meticulous astronomers and recorded the passage of the heavens in extraordinary detail. The goal was to mark the passage of time and to understand the will of the Gods who ...

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Here’s a little astronomical riddle for you: Which star in the late-autumn sky winks at us once every 2 days, 20 hours, and 49 minutes? Each wink lasts about 10 hours. If you identified the mystery ...

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