Algol is actually two stars. Star A is separated from close companion B by less than one tenth of the Earth-Sun distance, and partially eclipses every 2.9 days.
Click on image for star map
© Jens Dengler, reproduced with permission.

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Perseus

Algol

What's in a Name: Arabic for "head of the demon"
Claim to Fame: Represents Medusa's eye in Perseus. A special variable
star that "winks" every 3 days.
Type of Star: Blue-white Main Sequence Star, and a yellow Subgiant
How Far Away: 105 light years away
How Bright: Almost 100,000 times brighter than the Sun!
Where to View: In the constellation Perseus the Hero
When to View:November through March

Last modified March 1, 2005 by Travis Metcalfe.

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