Algol
Eclipsing binary, a pair of orbiting stars in the constellation Perseus, the fainter one of which eclipses the brighter one every 69 hours, causing the apparent brightness of the pair to drop by two-thirds.
The brightness changes were first explained in 1782 by English amateur astronomer John Goodricke. He pointed out that the changes between magnitudes 2.2 and 3.5 repeated themselves exactly after an interval of 2.867 days and supposed this to be due to two stars orbiting round and eclipsing each other.
The brightness changes were first explained in 1782 by English amateur astronomer John Goodricke. He pointed out that the changes between magnitudes 2.2 and 3.5 repeated themselves exactly after an interval of 2.867 days and supposed this to be due to two stars orbiting round and eclipsing each other.
© RM 2012. Helicon Publishing is division of RM.
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