The educational resource shows a visual about fixed stars: 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 are called fixed stars.

The educational resource shows a visual about the evolution of stars. The visual allows you to have an idea of the main properties of a star during its normal life, that is, not during its birth or its death.

The educational resource shows a visual about lunar phases: the moon is a rocky sphere about four times smaller than the earth. Its different aspects (as seen from the earth) are known as lunar phases.