March 2, 2021
AAVSO Forum threads (scroll to the bottom of a thread for latest posts):
- Campaigns and Observation Reports: https://www.aavso.org/asassn-21-co-campaign
- Eclipsing Binaries: https://www.aavso.org/asassn-21-co-campaign-01
- Spectroscopy: https://www.aavso.org/asassn-21-co-campaign-02
Note: Please continue observations at a cadence of 1 observation per week at least through 2021 June 15. See the post by Principal Investigator Dariusz Kubicki in the forum threads for this campaign (URLs below). - Elizabeth O. Waagen, 2020 June 29
The eclipse of EE Cep has occurred but continued monitoring is requested to establish post-eclipse behavior. - Elizabeth O. Waagen, 2020 May 21
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.
Edit: The information given in this alert notice has been updated to correct eclipse depth values. Please see AAVSO Alert Notice 594
August 16, 2017: The AAVSO is requesting monitoring of the eclipse of the very bright Algol-type eclipsing binary variable VV Cep, predicted to have begun in June 2017 and to conclude in November 2019.
June 30, 2017: Dr. Octavi Fors (University of North Carolina at Chapel Hill) and colleagues have requested AAVSO observers' assistance in following up on some targets from the Evryscope survey.
June 8, 2017: Dr. Milena Ratajczak (University of Wrocław) has requested AAVSO observers' assistance in monitoring the very bright (V = 4.23) and very unusual eclipsing binary HD 148703 (HR 6143, N Sco) during its infrequent primary and secondary eclipses scheduled for 2017 June 11 and June 14, respectively.
Observi
February 24, 2007
Don Davies discovered a 7th magnitude eclipsing binary (GSC 02484-00592, HD74057, VSX J084246.2+315145) in May, 2005, announced on our discussion group (posting 5/27/2005), and subsequently published in Peremennye Zvezdy:
http://www.astronet.ru/db/varstars/msg/1212913
The coordinates are
08:42:45.900 +31:51:41.00 J2000
and the approximate magnitude is V=7.18, with (B-V) = 0.56
THE AMERICAN ASSOCIATION OF VARIABLE STAR OBSERVERS
25 Birch Street, Cambridge, MA 02138 USA
BITNET: aavso@cfa SPAN: cfa::aavso
INTERNET: aavso@cfa.harvard.edu
Tel. 617-354-0484 FAX 617-354-0665
AAVSO ALERT NOTICE 155 (February 20, 1992)
NOVA CYGNI 1992 [V1974 CYG]
March 10, 2016: Further to AAVSO Alert Notice 537, the anticipated secondary eclipse of b Per is underway, according to information from campaign astronomer Dr. Donald F. Collins. Dr. Collins writes:
