What makes stars twinkle? The raging motion of the atmosphere, caused by wind and daily temperature changes.
The atmosphere is the thin blanket of air and gases that surrounds Earth. We need the atmosphere for breathing, but it makes work hard for astronomers. It is full of dust, pollution, clouds, and other things that block their view. Astronomers first tried to get above the problem by building observatories on mountains, where the air is thinner. They also put telescopes on balloons and airplanes. These things helped a little.
Then, in 1957, the first human-made satellite reached space. It gave astronomers a clear view, and space telescopes began to scan the skies.
