September 6, 2017: Further to AAVSO Alert Notices 591, 595, and 596, Dr. Boris Gaensicke (Warwick University) informs us that the date and time for the third and final of three HST observations in his campaign on the pulsating white dwarf-containing cataclysmic variable GW Lib has been scheduled for
August 31, 2017: Further to AAVSO Alert Notices 591 and 595, Dr. Boris Gaensicke (Warwick University) informs us that the date and time for the second of three HST observations in his campaign on the pulsating white dwarf-containing cataclysmic variable GW Lib has been scheduled for
[Note: If your variable star has an existing sequence, even if it is only one comparison star, please request assistance via CHET. This page is only for variables that have NO comparison stars. Thank you.]
Our own Donna Young has created an educational activity about variable stars on the HR Diagram. The activity is designed for formal K-16 educators and includes a teacher's guide, background material, student activities and answer keys.
However, the activity is also a great learning tool for those new to variable stars. It will introduce many of the most important types of variable stars and describe how they are related to other types. The genius of HR Diagrams is how they place everything in context of the grand scheme of things.
August 24, 2017: Further to AAVSO Alert Notice 591, Dr. Boris Gaensicke (Warwick University) informs us that the first of three HST observations in his campaign on the pulsating white dwarf-containing cataclysmic variable GW Lib has been scheduled for
August 17, 2017: In AAVSO Alert Notice 593 we announced a campaign on the very long period VV Cep M2Iabe+B0/2Ve binary. The amplitude of the eclipse was wrongly given as slightly under a magnitude in the V band when it is actually around 0.1 mag. This means that the VV Cep eclipse is largely undetectable visually, and is not a good candidate for visual observations. CCD and DSLR photometry, however, are still encouraged.
August 11, 2017: Dr. Gregory Sivakoff (University of Alberta) and colleagues have requested AAVSO observers' assistance in observing the black hole X-ray transient LMXB V404 Cyg in support of Chandra observations taking place TONIGHT. The Chandra schedule is
2017 Aug 11 23:49:04.072 - 2017 Aug 12 13:42:14.730 UTC
August 7, 2017: Dr. Boris Gaensicke (Warwick University) has requested our help in monitoring the pulsating white dwarf-containing cataclysmic variable GW Lib in preparation for and support of K2 (Kepler's Second Light) and Hubble Space Telescope (HST) observations scheduled for August to November 2017 and August and September 2017, respectively.
K2 will be observing GW Lib non-stop 2017 Aug 23 20:00:00 to 2017 Nov 19 23:00:00 UTC.
