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Note on automatic rejection of low signal-to-noise data

Note on Automatic Rejection of Low Signal-to-noise Data

Delta Scorpii: the birth of a Be star

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The Be stars

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.

Reporting DSLR Data

Over in the Citizen Sky forums we have begun a discussion about how to properly report DSLR data.
Click below to read the guidelines:

Alert Notice 441: Monitoring of Bright Giant Variables requested in support of ground-based spectroscopy and for long-term study

May 27, 2011: Dr. Steve Howell (NASA) and Dr. Travis Rector (University of Alaska, Anchorage) have requested AAVSO observations of several bright giant variable stars of diverse classes.  This request is for immediate support of spectroscopic observations to be made at Kitt Peak National Observatory between 2011 May 30 and 2011 June 01 (JD 2455712 - 714).  However, observers are encouraged to continue long-term monitoring of these objects.

Archival Data Digitization -- Work In Progress

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. 

Special Notice #234: Outburst of FS Aurigae

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.

Special Notice #233: Bright outburst of the cataclysmic variable SDSS J133941.11+484727.5

February 7, 2011: The star SDSS J133941.11+484727.5 has been reported in outburst by Jeremy Shears (Bunbury, UK).  Shears reports this star at magnitude 10.4 on 2011 February 7.919 (JD 2455600.419).  This is approximately 7 magnitudes above quiescence, which suggests a superoutburst of an SU UMa star or a WZ Sge-like outburst.  Gary Poyner (Birmingham, UK) confirms this outburst, estimating the star at 10.5 on February 7.959 (2455600.459).


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