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X Cygni

Amateur Astronomer Discovers the Cepheid X Cygni and Much More!


Zeta Geminorum

A Gem of a Star

Zeta Geminorum is often called the "kneecap" of the constellation Gemini.

Delta Cephei

The Model Star


Beta Lyrae

β Lyrae, known as Sheliak to the ancient Arabs and Tsan Tae to the ancient Chinese, was discovered to be a variable star by John Goodricke in 1784, about two years after his successful explanation of the light variations of Algol. In the more than two centuries since its discovery, β Lyrae has played a game of cat and mouse with astronomers attempting to unlock its secrets. Only slowly have some of those secrets been revealed.

Beta Persei (Algol)

"...the Gorgon's head, a ghastly sight, deformed and dreadful, and a sight of woe".
- Homer, writing of Algol in the Iliad.


Epsilon Aurigae

Author's note: This article was written prior to the start of the 2009-2011 eclipse.  Epsilon Aurigae was the focus of the AAVSO's Citizen Sky project. Please visit the Citizen Sky web site and get updated and expanded information about this exciting event.

U Monocerotis

At the Top of its Class


R Scuti

A Favorite Among Its Class


RV Tauri

RV Tauri — The strange prototype of a strange class

R Aquarii

R Aquarii: First and Foremost

Artist's<br />
Conception of R Aqr


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