Since its founding in 1911, the American Association of Variable Star Observers (AAVSO) has coordinated, collected, evaluated, analyzed, published, and archived
variable star observations made largely by
amateur astronomers and makes the records available to professional
astronomers, researchers, and educators. These records establish
light curves depicting the variation in brightness of a
star over time.
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AMERICAN ASSOCIATION OF VARIABLE STAR OBSERVERS. AAVSO