He passed the preliminary and went on to the finals. a boxing match or other athletic contest that takes place before the main event on the program: A preliminary was fought at 8:00. a preliminary examination, as of a candidate for an academic degree.
A light year is a measure of distance, or the distance a particle of light will travel through a pure vacuum in one Earth year. This distance is approximately 5.8785 x 1012 [5.87 trillion] miles, or 9.4605 x 1012 [9.46 trillion] kilometers.n one year, light can travel about 10 trillion km. One light-year is equal to 9,500,000,000,000 kilometers. A light year is the distance covered by light in one year travelling at 186,000 miles per second.
Similarly, Einstein calculated that the speed of light doesn't vary with time or place. What is a light-year? The speed of light can cause the universe to seem to host a time machine. The distance light travels in the course of a year is called a light-year. A light-year is a measure of both time and distance.