And How long is a light year?
When I was at school it was 300mps in a vacuum, slower in air or water A light year is the distance travelled by light in an year, a completely notional measure
A light year is a measure of distance, not time. Light travels approx 186,000 miles per second. It takes light from the Sun approx 8 minutes to reach us. In other words, the Sun could go out right now and we wouldn't be in the dark until 8 minutes pass.
According to the web site, The Unmuseum - Speed of Light, light travels at 186,000 miles per second, or 700 million miles an hour. This is a very informative and interesting article. Another web site you might try is The Speed of Light according to the Univ. of Va Physics Dept. As Captain Kirk, the commander of the Enterprise used to say, beam me up Scottie! A light year is the distance light can travel in one year.
the speed of light = 299 792 458 m / s Not in miles though, it is meters per second In imperial units, the speed of light is about 670,616,629.2 miles per hour or 983,571,056 feet per second, which is about 186,282.397 miles per second, or roughly one foot per nanosecond. or ~9,500,000,000,000 kilometers or ~5,900,000,000,000 miles
