Yep, when we look through the eyepiece, we can see Venus. Hey, it's starting to get cold out here. The largest optical telescope in the world is in Hawaii. It's the 10-meter W. M. Keck telescope. At 4300 meters, it sits on top of Mount Mauna Kea, an extinct volcano.
Radio telescopes use a large dish to collect radio waves from space.
The dish is the same shape as the mirror of a reflecting telescope. Radio telescopes are a valuable tool for astronomers since many objects in the universe do not produce enough visible light to be picked up by optical telescopes. The VLA is made up of 27 linked radio telescope dishes each 25 meters in diameter. Every year astronomers find out something new about the universe. Last year the Hubble Space Telescope was a big help to researchers.