Variable Star of the Season Archive

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.

V2362 Cyg (Nova Cygni 2006)

On April 2, 2006 H. Nishimura of Japan discovered a 10.5 magnitude nova based on two photographs taken with his Pentax camera. Similar photos (limiting magnitude 12) showed no object as recently as March 28 of that year, and CCD measurements taken soon after  found the object had brightened to 8.5 on April 4/5 (Green 2006). The maximum occurred shortly thereafter, reaching magnitude 8.1. Pre-maximum spectra were obtained, and initial data suggested that this object was a fast Fe-II iron-type nova.

The Trapezium, BM Orionis, and Young Stellar Objects

Just over one year ago, a small spacecraft called MOST began a month-long observing run on one of the most spectacular objects in Earth's skies, the beautiful Trapezium region at the heart of the Orion Nebula, M42.  My collaborators and I applied for and received this observing time to survey variability in this young stellar cluster -- partly to study the eclipsing binary BM Ori (theta 01 Orionis B), but also to survey as many young stars that we were able to using the unique capabilities of MOST.  Since then, I along with my collaborators -- our Director Arne H

Delta Scorpii: el nacimiento de una estrella Be

This is also available in English

Las estrellas Be

El estadio Be no es sólo una etapa evolutiva en las vidas de algunas estrellas calientes de tipo B de rápida rotación sino también un fenómeno transitorio que puede ir y venir con el paso de los años en la misma estrella.  Varias razones se han propuesto para explicar el comportamiento de estas estrellas y aun están en debate.