Astronomical distance refers to the vast spaces between celestial objects in the universe. To measure these distances, astronomers often use units like light-years, which is the distance light travels in one year, approximately 5.88 trillion miles (9.46 trillion kilometers). This unit helps convey the immense scale of the universe, where even the nearest star, Proxima Centauri, is about 4.24 light-years away from Earth. Another common unit for measuring astronomical distances is the parsec, equivalent to about 3.26 light-years. The term "parsec" comes from "parallax arcsecond," which relates to the method of measuring distances based on the apparent movement of stars against distant backgrounds as Earth orbits the Sun. Understanding these distances is crucial for studying the structure and evolution of the universe.