- from Telescopes
A look into the night sky is a trip into the past. Why? Because even though light zips along at 186,282 miles per second, it still takes time to travel long distances.
Take the star Bellatrix in the constellation Orion, for example. It is so far from Earth that the light we see from it is 300 years old!
A telescope that can gather and focus visible light can see deeper into the past than a naked eye. That’s because it is bigger than an eye and can collect more light. What happens when it brings that light into focus? It gives us a magnified image. Two types of optical telescopes are refractors and reflectors.