The Wierd World of Cataclysmic Variable Stars

Historians debate whether the first confirmed variable star was Mira (a.k.a. Omicron Ceti, with observations recorded in 1596), or Algol (a.k.a. the Demon star, with observations recorded in 1667 - but which may have been known in antiquity). Since then, thousands of variable stars have been identified. Over the past century astrophysicists have begun to understand why these "stars" rapidly change brightness. Yesterday's "variable stars" are now realized to be a menagerie of strange celestial objects – including stars in birth throes, eclipsing binaries, stars in death agonies, and the bizarre world of cataclysmic variables.

After briefly reviewing the intriguing history of mankind's discovery of variable stars, the presentation will focus on cataclysmic variables. The stars in these binary systems are so close their orbit would fit inside our Sun! They revolve around each other in a matter of hours; matter flowing between the stars creates a disk which can change in brightness by a factor of over a hundred in just a few minutes. Cataclysmic variables are one of the most studied areas in astronomy today. Amateurs are playing a key role in the measurement and analysis of these systems working through the AAVSO and the Center for Backyard Astrophysics. Opportunities to get personally involved with be discussed.

Speaker: Gordon Myers