The light year (ly) is a unit of length that is the distance light travels in a vacuum in one Earth year. One light year is approximately 9.46 trillion kilometers (9.46 x 1012 km) or 5.88 trillion miles (5.88 x 1012 mi). The light year is used to describe distances to stars without having to use very […]
It never gets truly dark at night because of an effect called airglow. Airglow is similar in color to the aurora, but you don’t have to visit a polar region to see it. While the aurora is light released by the interaction between magnetosphere and the solar wind, airglow is […]