Rossiter-Mclaughlin effect in the eclipsing binary star system
A binary star is a stellar system that consists of two stars orbiting around their center of mass. It is estimated that about half of all stars are binary. If binaries orbit in a plane containing our line of sight, they will eclipse each other; these are called eclipsing binaries. When stars eclipse in this way it causes the brightness to vary, and this effects their light-curves because when a star is eclipsing another we see less light. The size of the stars, the distance between them and how much of the other star one star covers also determines how the curve may look. We observe a phenomenon of the spectrally and photometrical observed R-M effect in eclipsed binary stars. R-M effect has been observed in many captured binary star systems. Its amplitude depends on the depth of eclipse. Other things being equal, the rotation speed of the star is very large.