Why do stars twinkle? It’s the wild motion of the atmosphere, caused by wind and daily temperature changes.
The atmosphere is the thin blanket of air and gases around Earth. We need the atmosphere for breathing. But it’s bad news for astronomers. It’s full of dust, pollution, clouds, and other stuff that blocks their view. Astronomers first tried to rise above the problem by building observatories on mountains, where air is thinner. They also put telescopes on balloons and airplanes. These things helped a little.
In 1957, the first human-made satellite went into space. At last astronomers had a clear view. Soon space telescopes began to scan the skies.
