Because we're creating a 95% confidence interval, this means we have two tails of 2.5%. When we look up 0.025 in the Z table (click to open) , we find that it corresponds to a z-score of 1.96. After plugging everything into the equation, we find a lower bound of 480.8 and an upper bound of 559.2.
As already noted, the speed of light (expressed in meters per second) means that light travels a distance of 9,460,528,000,000 km (or 5,878,499,817,000 miles) in a single year. This distance is known as a âlight yearâ, and is used to measure objects in the Universe that are at a considerable distances from us.
| Cool Cosmos. The Hubble Space Telescope can see out to a distance of several billions of light-years. A light-year is the distance that light travels in 1 year. Since light has a speed of 186,000 miles per second (light can travel about 7 times around the entire earth in 1 second!), light travels about 5,865,696,000,000 miles in just one year.