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AAVSO International Database

Special Notice #219: Eclipse of the symbiotic star CI Cygni

October 12, 2010: As noted by U. Munari et al (ATel #2913, 2010 October 9), the symbiotic star CI Cygni is currently undergoing an eclipse of the outbursting star.  CI Cyg has declined from about magnitude 9.7 in late August 2010 to V=11.1 currently.

Alert Notice 426: Rescheduled request for observations of V455 AND in support of HST observations

October 5, 2010: As originally announced in AAVSO Alert Notice 423, Dr. Paula Szkody (U. Washington) has requested the help of AAVSO observers in monitoring the WZ Sge-type cataclysmic variable V455 And in support of Hubble Space Telescope ultraviolet spectroscopic observations.

AAVSO Maxima and Minima for Long Period Variables: Data Access

These data are formally published for the years 1900 to 2008.  For a description of this data set, please click here.


Note: a separate page exists for the data including unpublished times of maxima.  Go here for the current data set including the most recent data (through February of the current year).

Stars with maxima and minima data are as follows:

Special Notice #218: Outburst of the UGWZ star SDSS J080434.20+510349.2

September 21, 2010: As announced by Hiroyuki Maehara in vsnet-outburst 11547, the WZ Sge-type dwarf nova SDSS J080434.20+510349.2 is in outburst, and is also showing evidence of superhumps (vsnet-outburst 11551).  Both visual and CCD observations -- including CCD time-series observations -- of this outburst are encouraged.  The most recently posted visual observation by Patrick Schmeer (vsnet-outburst 11556) indicates the star is currently around m(vis) = 12.7.

AAVSO Maxima and Minima of Long Period Variables, 1900-2008

Elizabeth O. Waagen, Janet A. Mattei, and Matthew R. Templeton

Click here for data access

Introduction

Long-term observations of long period variable stars are essential to the determination of period, change in period, change in behavior resulting from mass loss and/or evolution, mode of pulsation (fundamental or overtone), internal structure, and phase at specific times for these stars.

Alert Notice 423: Request for observations of V455 AND in support of HST observations

August 30, 2010: Dr. Paula Szkody (U. Washington) has requested the help of AAVSO observers in monitoring the WZ Sge-type cataclysmic variable V455 And in support of Hubble Space Telescope ultraviolet spectroscopic observations scheduled for 6:55-15:20 2010 September 11 UT (the night of Friday, September 10/11) (JD 2455450.78819 - 2455451.13889). Observations are requested beginning immediately and continuing through September 20. This monitoring is crucial to these observations.

Special Notice #215: Brightening of the symbiotic star CI Cyg

August 24, 2010: Observer Gary Poyner (Birmingham, UK) reports that the symbiotic star CI Cygni has noticeably brightened over the past few days.  Poyner reports the star at a magnitude of m(vis)=9.8 on 2010 August 23.92 (JD 2455432.42). CI Cyg has been in a slow rise for several months, beginning immediately after the end of the last outburst.  Continued monitoring of CI Cyg over the next several weeks and months will be useful for better understanding the nature of this star system and its outbursts.

Special Notice #214: Outburst of V592 Her

August 1, 2010: Maciej Reszelski has reported an outburst of V592 Her at CR=14.14mag. This WZ Sge variable last had a superoutburst on August 26, 1998, when it reached 12th magnitudes. In quiescence, V592 Her is fainter than 20th magnitude.

V592 Her is located at RA 16 30 56.37 DEC +21 16 58.2 (J2000).

AAVSO Validation Project

Data Validation

The AAVSO Data Validation Project was a two-year project begun in 2002 where AAVSO staff examine every visual observation in the AAVSO International Database made between 1911 and 2001.  This project has been completed, and all AAVSO Light Curves are now available directly via the AAVSO Website.  A summary of the Validation Project was published by Malatesta et al. in the Journal of the AAVSO, volume 34 (2006).

Pages

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