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Looking at the night sky is like traveling to the past. Why? Well, light zips along at 186,282 miles per second. But 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 collect and focus visible light can see deeper into the past than just your eye. That’s because it is bigger than an eye. So, it can collect more light. What happens when it brings that light into focus? It gives us a magnified (bigger) image. Two types of optical telescopes are refractors and reflectors.