August 2, 2019: These HST observations of V386 Ser have been rescheduled to August 15-16. Please see AAVSO Alert Notice 675 for further information and updates. - E. O. Waagen, AAVSO
Note: In the original version of this Alert Notice, it was omitted that the rebrightening of V1047 Cen (Nova Cen 2005) was discovered and reported by the Gaia team as Gaia19cfn on June 10, 2019. The target was subsequently observed by OGLE. We apologize sincerely for the omission of this discovery information. - Elizabeth O. Waagen
As usual, the AAVSO Sequence Team has been working hard updating and improving charts and comparison star sequences. The following is a list of updates made during the first six months of 2019. If you observe any of these objects please update your charts and photometry tables with the most recent version as soon as possible. This list is also available for download in XLSX and PDF format (see the links at the bottom of this page.)
Updated May 24, 2019: Dr. Paula Szkody informs us that the exact time for the HST observation of V386 Ser has been scheduled for 2019 May 30 04:36-10:15 UT. This is the night of May 29/30 for US observers. Thus, the critical night will be May 28/29 (Wednesday night) to get a measurement to HST so they can proceed to the observation. It will be essential to have positive observations from this night to satisfy the HST planners, so observers with suitable equipment are urged to obtain positive measurements of this faint star.
May 14, 2019: Dr. Mark Kennedy (Jodrell Bank Centre for Astrophysics, University of Manchester) is urgently requesting observations of the potential cataclysmic variable CRTS J105122.8+672528 beginning immediately. This object appears to be in outburst, having brightened to V~16.2 from its minimum magnitude of V~18.5-CV~19.
Reach for the stars by participating in the AAVSO 2019 Annual Fundraising Campaign! Your generous contribution will support the AAVSO today and nurture the next generation of star gazers.
Note: Dr. Margarita Karovska (Harvard-Smithsonian Center for Astrophysics) is also urgently requesting BVRI photometry, visual observations, and spectroscopy of R Aqr through (at least) the end of the observing season. - Elizabeth O. Waagen, August 5, 2019
Note: R Aqr is out of its seasonal gap and is increasingly observable. Continued coverage is requested as described below until further notice. - Elizabeth O. Waagen, May 3, 2019
