If the distance between stars and planets or stars and stars were measured in miles the numbers would be so large we would not be able to contain them on one page. Astronomers use light-years to make these measurements so they numbers are less overwhelming. A light year is the distance that light travels in 1 year. Light travels at 186,282 miles in one second! A light year is 5.88 million million miles or 5,880,000,000,000 miles. The nearest star, excluding the sun, to earth in Alpha Centauri which is 4.3 light-years away or the equivalent of 25 million million miles from earth. It would take 8.5 years for us to send a message and get a response from this star. Stars in the Milky way can stretch up to 80,000 light-years away from earth.