Science educator and engineer Bill Nye explains what a light-year is, why we have a unique measurement for outer space, and why it’s “the coolest thing ever that there’s so much we don’t ...

Bill Nye: A light-year is how far a beam of light travels in a year -- (over) 5.88 trillion miles. When scientists or astronomers use the shorthand "light," what we mean is the speed of light for ...

By Danya Gainor, CNN No matter what the James Webb Space Telescope, Hubble Space Telescope or our other tools of space exploration discover next, it’s likely to be located many light-years away ...