What is an "eye examination"?

It is a single-aperture spherical radio telescope with independent intellectual property rights in China, which is used to explore the universe. With it, we can promote the understanding and exploration of the deep space of the universe and provide new possibilities for the development of astronomy.

How big is the 500-meter spherical radio telescope (FAST)? Its diameter is 500 meters, and its launching area is equivalent to the size of 30 standard football fields. If filled with mineral water, 7 billion people around the world can share 4 bottles on average. How far can it see? You can see through the area over13 billion light years, close to the edge of the universe. At present, the 500-meter spherical radio telescope (FAST) is the largest and most sensitive single-aperture radio telescope in the world. Based on the principle of parabolic antenna, the scientific name of "500-meter spherical radio telescope (FAST)" is 500-meter spherical radio telescope. Unlike ordinary optical telescopes that observe through visible light, radio telescopes "observe" the universe by receiving invisible radio waves in the universe. There are two "windows" in the thick atmosphere above us: one is the visible light window, through which human beings have observed the universe for thousands of years; One is the radio window. In 1930s, karl jansky, the pioneer of radio astronomy, accidentally discovered the signal from the center of the Milky Way, which opened the curtain of radio astronomy and promoted the understanding of the universe and the origin of life.