Variables: What Are They and Why Observe Them?
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What Are Variable Stars?
Variable stars are stars that change brightness.
Variable stars are stars that change brightness.
Variable Stars and the Stories They Tell: Exoplanets and the Search for Extraterrestrial Life
©February 2018 by Dale Alan Bryant
(In memory of M.I.T. astrophysicist Dr. Philip Morrison - who started all this...)
Though the figures are tough to keep up with - they are changing, almost daily - the Kepler Space Telescope (KST) has discovered, to date, over 4,500 exoplanet candidates, ~3,400+ of which have been confirmed.
AAVSO Bulletin 81: Predicted Dates of Maxima and Minima of Long Period Variables for 2018 has been published. This annual publication covers the period January 2018 - February 2019 and gives predicted extrema dates for 381 Long Period Variables in the AAVSO's Legacy LPV program.
The following articles contain useful and interesting information on individual variable stars. Many of the most popular stars in the AAVSO observing program are featured. From December 1998 until December 2002, the collection of articles comprised the "Variable Star of the Month" series. Since that time, they have all been published as part of the "Variable Star of the Season" (VSOTS) collection.
The American Association of Variable Star Observers (AAVSO) and the British Astronomical Association Variable Star Section (BAAVSS) are pleased to announce that the variable star observation archive of the BAAVSS is now available through the website of the AAVSO. The BAAVSS archives comprise over 2.5 million variable star observations made mostly by amateur astronomers world-wide over the past 150 years. These data now join the archives of the AAVSO in the AAVSO International Database, which consists of over 25 million variable star observations made by observe
The term "sunspot" appears in the news, often in connection with stories on aurorae, electrical outages, and problems with orbiting satellites. But often these stories don't really explain what sunspots are and why they're of interest to us on Earth. So what are sunspots?
The AAVSO's volunteer-driven project to digitize paper archives of variable star observations is moving forward, and there have been some exciting developments over the past few months that deserve to be mentioned. Here, I'll summarize some of the happenings in this project, and talk about some of the issues that have arisen at AAVSO and among the volunteers.