AAVSO VSX Portal

www.aavso.org (enter star name e.g. “RV Vel” in the Star Finder, click Search VSX, click on the target name, then open the External Links menu.)

ASAS3

http://www.astrouw.edu.pl/asas

BRNO O-C Gateway

http://var.astro.cz/ocgate/

CALEB Catalog & Atlas

http://caleb.eastern.edu/

David Motl’s Ephemerides program

Freeware from http://www.motl.cz/dmotl/predpovedi/

The SPADES Ephemerides file

The best source of up-to-date ephemeris data on our targets. {jd_file file==190}.

General Catalog of Variable Stars

http://www.sai.msu.su/gcvs/gcvs/

Krakow O-C Atlas

http://www.as.up.krakow.pl/o-c/

SuperWASP

http://www.wasp.le.ac.uk/public/