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Z Camelopardalis

Astro-1<br />
Official Patch Astro-2 in space


EX Hydrae

Meet EX Hydrae

RY Sagittarii

Rebels With a Cause?

R Coronae Borealis

Prepared by Kate Davis, AAVSO Technical Assistant, Web - January 2000

The Enigmatic R Coronae Borealis...


Mu Cephei

Mu Cephei - A Most Beautiful Object

Z Ursae Majoris

Prepared by Kate Davis, AAVSO Technical Assistant, Web - March 2000


EU Delphini

EU Delphini and the Small-Amplitude Pulsating Red Giants

Pulsating Red Giant Stars

Alpha Orionis (Betelgeuse)

 Note: This page was edited to modify the magnitudes of comparison stars Procyon (0.5 to 0.4 V) and Aldebaran (1.1 to 0.9 V) and to add the link to the chart available via the AAVSO's 10-Star Tutorial. - Elizabeth O. Waagen, 6 January 2020

V725 Sagittarii

The Remarkable Transformation of V725 Sgr


W Hydrae

Near the tail end of the expansive constellation of Hydra the sea serpent resides the bright southern semiregular-type variable star W Hydrae. The period of W Hya is just shy of a year at 361 days. Based on over 3,400 observations in the AAVSO International Database, the variable has a magnitude range of 5.7-10.0, making W Hya a great star for observers with binoculars and/or small telescopes who can observe to -28 degrees declination.



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