In this second type of binary, the presence of two stars is indicated by periodic eclipses. Eclipsing binaries are one type of variable star. Algol is a prime example of a classical eclipsing binary. Algol was the first star recognized to be an eclipsing binary by John Goodricke back in 1782, and is a very easy star to find for the rest of us. Sky & telescope magazine provides a list of the times of minimum light for Algol.  Eclipsing binaries are fairly easy to understand.  The two stars in these systems need to be rather close to each other in order to block each other’s light.  We plot this changing brightness on what is called a light curve.  The orbital periods would be on the order of days, if not hours.   Because of the periodic eclipses, these binaries appear as variable stars Some eclipsing binaries have dramatic changes in brightness, whereas some don’t change by more than a hundredth of a magnitude.   So much depends on the orbit.  Try this simulation.  The most famous eclipsing binary is Algol, discovered by John Goodricke two hundred years ago.  Here is a video about The Demon Star. You will be doing the lab on eclipsing binary stars, using the simulation found in the link above.
Looking for a particular star?  Find it here!
Eclipsing Binary Stars
Carpe Caelum
Carpe Caelum Stellar Astronomy
Carpe Caelum Stellar Astronomy