Z Andromedae
Prepared by Kerri Malatesta, AAVSO Technical Assistant.
Prepared by Kerri Malatesta, AAVSO Technical Assistant.
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The variable star CH Cygni lies in the constellation Cygnus just under the western wingtip of the swan. |
The symbiotic variable star CH Cygni is a rewarding star
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The Henry Draper (HD) Catalogue, named for the first photographer of stellar spectra, is a nine volume publication (released from 1918 through 1924) that contains the positions, though not accurat |
The Unusual RR Lyrae Star AH Leo
Introduction
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The constellation Cygnus |
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"After" and "Before" Supernova 1987A |
Sixteen years ago, you might have looked up at the night sky and expected to observe T Pyxidis shining at a brilliant 7th magnitude - in outburst for the sixth time since 1890. You would have been disappointed though, because there was no outburst that year, or the year after ... or the year after that. In fact, for a recurrent nova with an average of 19 years between outbursts, T Pyxidis is more than fashionably late to the party. This star is way overdue for an outburst and when it happens, some people think it is going to be a big one.
Located in the equatorial constellation of Ophiuchus lies the variable RS Ophiuchi. RS Oph belongs to the cataclysmic variable (CV) class of stars, and is further classified as belonging to a smaller, seemingly "exclusive" group of CVs termed recurrent novae (NR) - of which there are only 7 confirmed members.
The recurrent nova U Scorpii
This summer's Variable Star of the Season is delta Scuti and the class of variables which carries its name. Because they are low amplitude variables, they will be challenging to visual and CCD observers alike, but we hope it's a challenge you will all enjoy! A diverse class of very short period stars, the delta Scuti variables have something for everyone. Some have amplitudes of nearly one magnitude and regular light curves like some of the RR Lyrae stars and Cepheid variables.