RR Lyrae
From Wikipedia, the free encyclopedia.

RR Lyrae is a variable star in the Lyra constellation. It is the prototype of the RR Lyrae variables star class. It has a period of about 13 hours, and oscillates between apparent magnitudes 7 and 8.

See also: RR Lyrae variable

The original article can be found at: http://en.wikipedia.org/wiki/RR_Lyrae.
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