Alert Notice 443: Long-term monitoring of four AGN in support of ground-based spectroscopy
[Edited 2011 July 12 to indicate that the apertures and annuli are radii rather than diameters. -- M. Templeton, AAVSO]
[Edited 2011 July 12 to indicate that the apertures and annuli are radii rather than diameters. -- M. Templeton, AAVSO]
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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.
The AAVSO has a policy in place that states positive observations having errors equal to or greater than 1.0 magnitudes are not accepted as is. For a given measurement, an error of 1.0 magnitude is equivalent to a signal-to-noise ratio of 1, meaning that the purported signal is indistinguishable from the average noise fluctuation in the data and statistically is not a significant detection.
Be-ness is not only an evolutionary stage in the lives of some rapidly rotating hot B-type stars but also a transient phenomenon that may come and go over the years for the same star. Several reasons have been proposed to explain the behavior of these stars and are still in debate.
Over in the Citizen Sky forums we have begun a discussion about how to properly report DSLR data.
Click below to read the guidelines:
Note: Ongoing optical coverage of these targets is requested. - Elizabeth O. Waagen, April 20, 2021
A thread for this campaign has been created in the AAVSO Campaigns and Observation Reports discussion forum: https://www.aavso.org/bright-giant-variables-campaign
March 30, 2011: The cataclysmic variable NSV 1436 has been discovered in outburst. This is the first bright outburst of this star observed since 1948, and followup observations are strongly encouraged. Little is known about the nature of NSV 1436, and observations may help shed light on whether the star is an infrequently outbursting normal dwarf nova, a WZ Sge star, or recurrent nova.
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.
Note: This chat is over. A transcript can be found here.
February 14, 2011: Further to AAVSO Alert Notice 428 (2010 Nov 30), the dwarf nova FS Aurigae appears to be in outburst. The current outburst was detected simultaneously by P. Lake (Wonga Park, Victoria, Australia) at m(vis)=14.5 on 2011 Feb 14.0969 (JD 2455606.5969), and confirmed shortly after by G. Lubcke (Middleton, WI, USA) at around V=14.4 in time-series observations made simultaneously to the observation of Lake. Follow-up photometry of this star is encouraged.