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Bob Nelson's O-C files for EBs 2012 edition

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.

How to Use the EB Ephemeris

The AAVSO Eclipsing Binary Ephemeris provides the predicted time of mid-eclipse for eclipsing binaries in the AAVSO Eclipsing Binary observing program. These times appear in Universal Time in the body of the ephemeris table. The time is rounded to the nearest half hour, which provides sufficient accuracy to plan an observing session while, hopefully, leaving sufficient doubt about the exact time in order to eliminate anticipatory bias. The ephemeris is designed for use by observers at American longitudes.

Eclipsing Binary Ephemerides

How to Use the EB Ephemeris

An expanded eclipsing binary ephemerides can also be found at the Milwaukee Astronomical Society website.

RR Lyrae Ephemerides

How to Use the RR Lyrae Ephemeris

The following RR Lyrae Ephemerides are available in Adobe PDF format.

Prepared by G. Samolyk

AAVSO 49 Bay State Rd. Cambridge, MA 02138 617-354-0484