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VX Hydrae: Observation of a Sudden Change in a Pulsating Star

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Michel Bonnardeau
116 Jonquille Arzelier, 38650 Chateau-Bernard, France

Shawn Dvorak
Rolling Hills Observatory, 1643 Nightfall Drive, Clermont, FL 34711

Rudy Poklar
14084 N. Willow Bend Drive, Tucson, AZ 85737

Gerard Samolyk
P.O. Box 20677, Greenfield, WI 53220


Time-series of VX Hya from March 2005 to April 2010 are analyzed. A period jump is discovered to happen in 2008 in all the pulsation modes, being at its strongest for the overtone.

AAVSO 49 Bay State Rd. Cambridge, MA 02138 617-354-0484