Majority of stars in our Galaxy are not alone, possibly with a family of planets, but they occur in pairs (binary stars) or even higher-count systems (triple stars, quadruple stars, …).

When the orbital plane of binary star orbit is oriented (at last approximately) in the direction towards our Sun, we can observe mutual eclipses of both stars. In such case brightness of such star periodically drops and the star reveals itself as an “eclipsing binary”. (Remember, no telescope can distinguish close binary star as two points, they always appear as single star. So, if no eclipses occur from our point of view, chances to discover any particular star is a binary are very low as only time consuming and expensive acquiring of spectrum using some giant telescope can reveal it.)

There are hundreds of thousands (or maybe millions) of eclipsing binary stars observable on our sky. But only rarely more binary stars in multiple-star systems show eclipses. At the same time such exceptional cases are important as they allow to us study many aspects of stellar evolution, migration of stars or even planes in planetary systems and other important questions of current astrophysics. The image above shows how brightness changes of double-eclipsing quadruple star system CzeV1640 reveal itself in light curve (top panel) and also brightness changes of both eclipsing binaries with influence of the complementing binary mathematically removed (bottom left and right panels).

This particular quadruple star was discovered using G4-16000 CCD camera on 30cm custom-built telescope. We are really happy when we see our cameras not only providing beautiful and breathtaking images, but also contributing to our understanding of the universe we live in. More details about the CzeV1640 quadruple star system are available online Res. Notes AAS 3 80.