How long is a light-year?

A light-year is a unit of measurement used in astronomy to determine vast distances in space. It is defined as the distance that light travels in one year in a vacuum, which is approximately 9.461 trillion kilometers. Since light moves at a speed of about 300,000 kilometers per second, it covers an enormous distance in one year, resulting in this massive measurement. Therefore, when we say that a star or galaxy is, for example, 10 light-years away, we mean that the light from that object takes 10 years to reach Earth, traveling through empty space at an unimaginable speed.