What is an eclipsing binary?

An eclipsing binary is defined as a binary star system where one star passes in front of another from our perspective on Earth. This configuration leads to periodic dimming of the combined light from the stars as the foreground star obscures the light from the background star. The study of eclipsing binaries is significant because these systems allow astronomers to measure the properties of the stars, such as their sizes and temperatures, by analyzing the light curves that record how the brightness changes during the eclipses.

In contrast, the other options describe different astronomical phenomena. A star that emits high energy across vast distances describes a type of astrophysical object but does not relate specifically to the dynamics of binary star systems. The mention of two stars in the same galaxy cluster pertains to the grouping of stars but does not involve the specific interactions seen in eclipsing binaries. Lastly, a collapsing star that forms a supernova refers to the death of a massive star, which is entirely different from the behavior of binary systems, particularly eclipsing binaries. Thus, the correct definition captures the essence of how the stars interact in their eclipsing behavior.