The brightness of variable stars, exemplified by Algol (Beta Persei), can be estimated by comparing their visual magnitude to nearby stars of known magnitudes. Algol, an eclipsing binary star system, ...

Lauri Jetsu, an astrophysicist at the University of Helsinki, is following a tradition that may stretch back thousands of years. For more than a decade, he’s studied the bright star Algol, one of the ...

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 ...

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 ...

According to a legend, more than two centuries ago, a famous Paris astronomer used to stand on one of the Seine bridges on nights when the variable star Algol was in eclipse, to point out this ...

A lovely constellation that straddles the Milky Way is Perseus, the hero, which is visible in the northern skies from July to March. Its stars arc from Capella, in the constellation Auriga, to the "W" ...

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 ...

The Ancient Egyptian papyrus Cairo 86637 calendar is the oldest preserved historical document of naked eye observations of a variable star, the eclipsing binary Algol -- a manifestation of Horus, a ...

ON the evening of October 29, while examining the Pleiades with a binocular at about 9 p.m., G.M.T., I noticed that the star Atlas (27 Tauri) was slightly fainter than Pleione (28 Tauri), a little to ...

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