RR Lyrae Variable Star Notes

General RR Lyrae Information

RR Lyrae Stars are a class of variable star which have a period of luminosity between 0.2 and 1 Day. Another useful thing is that they all have the same period to absolute magnitude ratio, which means by just measuring their brightness from earth, we can tell how far away they are since they are a type of standard candle. They are usually too faint to be identified in far away galaxies, but they can be observed with large telescopes in the Andromeda Galaxy, and much smaller telescopes in the Milky Way. Globular Clusters are usually a hotspot for finding RR Lyrae variables, as I divulge below.


Turned out better than the faint M79 with the 14 incher. Look carefully and you can spot a few RR Lyrae stars getting brighter and dimmer in this animation.
M3 Animation


M79 was too distant and the seeing was too poor to reliably measure any RR Lyrae stars.
SEDS M79 Page
List of known variables


Plans to go out and observe M79 then look for RR Lyrae in the combined animation of the night. Transit is around 9.10 locally, which will interrupt any observation in the time given.

Link Stockpile

M3 Astronomy Picture of the Day
M3 Movies
AAVSO RR Lyrae Program
Washington.edu M4 Lab
UToronto listing of Globular Cluster Variables