Today we know that the sun is no more than a star which is near to us. Stars like the sun, which are large gaseous spheres, of which 99% is hydrogen and helium, are called fixed stars. In their centre there is a continuous nuclear reaction, much more powerful than our hydrogen bombs, which maintains their surface at a temperature of thousands of degrees.
Fixed stars are distributed randomly in the sky making groups we call constellations. Now let's ask some questions:
Are all the stars the same distance away? Are they all alike? Are the so-called fixed stars really immobile?
The following visual will help you answer these questions.



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