Sky

The sky is the outermost part of the earth's surface. Atmosphere and space are also part of it.

In astronomy, the sky is also called the B-sphere. From the surface it is imagined to be an imaginary sphere where the sun, stars, moon and planets are seen orbiting. The B-sphere is usually divided into different constellations. The word sky is usually used to indicate any point above the surface. But its meaning and usage may be different. For example, in the case of weather, the sky refers only to the more dense part of the lower part of the atmosphere.

The sky looks blue for scattering light in daylight. And at night the sky looks like a black carpet full of stars. If there are no clouds during the day, the sun can be seen in the sky. And in the night sky (sometimes even during the day) the moon, the planets and the stars are visible. Natural phenomena such as clouds, rainbows, auroras or poles, lightning, etc. are observed in the sky.