Note: Some of the targets below are being re-assessed for continued coverage. For the present, please continue to observe all targets. - Elizabeth O. Waagen, September 30, 2024
The Alert Notice text below has been revised from the original version issued April 18, 2024. - Elizabeth O. Waagen, April 19, 2024
Note: The Alert Notice text below has been revised from the original version issued April 18, 2024. - Elizabeth O. Waagen, April 19, 2024
Observers are also reminded that it is essential to use the comparison and check stars indicated for the photometry target. If they are too far apart to fit into the same field of view as the target, use PEP-style observing, that is, alternate images of variable, comp, and check.
April 22, 2024 REVISED VERSION
The O’Connell effect is a phenomenon found in eclipsing binaries where the maxima between eclipses are not equally bright. It was first described by Roberts (1906), codified by O’Connell (1951), and named the O’Connell effect by Milone (1968). Despite being known for over a century, however, the physical processes underlying the O’Connell effect are still shrouded in mystery.
The 2021 Eclipsing Binary Ephemeris is now available.
Thank you Gerry Samolyk for all the good work you put into this!
May 6, 2020
AAVSO Forum thread (scroll to the bottom of a thread for latest posts):
- Exoplanets: https://www.aavso.org/tyc-24831601-observation-alert
Dr. Dennis Conti (AAVSO) provides the following information:
The EB Zoo: examples of eclipsing binary stars and their behaviours
In this zoo, we will display not the specimen light curves of various types of EBs (these are readily available elsewhere), but the changes in their behavior. Such changes are what most amateur observing programs aim to find and track. Specifically, here are examples of EBs whose eclipses come early or late for different reasons, and a case where the eclipses no longer happen(!).
Some of the best opportunities for contributing to astronomical research come through the AAVSO's Observing Campaigns, which are observing projects requested by individual researchers with a specific goal in mind. Some Campaigns are designed to last for a long time, and the results aren't known until well after the campaign concludes. But some campaigns pay off immediately. Our campaign on the bright star b Persei is an example of the latter, with a handful of AAVSO observers getting exactly the right data, at the right time, right away!
January 7, 2015: Dr.
The AAVSO is happy to provide a copy of Bob Nelson's O-C files for Eclipsing Binaries for 2012. These files can be used for observation planning, and are a valuable resource for EB observers.
Thanks once again for Bob Nelson for providing this service to the EB community.
