What term refers to two stars orbiting each other where one regularly passes in front of the other?

What term refers to two stars orbiting each other where one regularly passes in front of the other?

• A. Double star
• B. Eclipsing binary
• C. Red giant
• D. Supernova

Answer: (B)

The term "eclipsing binary" specifically refers to a system of two stars that orbit each other in such a way that one star regularly passes in front of the other from our viewpoint on Earth. This alignment causes periodic dimming of the light that we receive from the system, as the foreground star temporarily obstructs the light from the background star.

Eclipsing binaries are important for astronomers because they can provide valuable information about the size, mass, and composition of the stars involved. By analyzing the light curve—the graph of brightness over time—scientists can determine the orbital period and the relative sizes of the stars.

In contrast, a "double star" is a more general term that simply indicates two stars that are close together in the sky, but they may not necessarily experience eclipses. "Red giant" refers to a specific stage in the life cycle of a star when it has expanded and cooled, while "supernova" describes the explosive death of a star at the end of its life cycle. Neither of these terms relates to the specific interaction of two stars overshadowing one another as occurs in an eclipsing binary.