What's under the earth?

The earth belongs to the solar system. In all directions of the solar system, there is a huge galaxy, and in all directions of the galaxy, there is almost endless space.

Seen from the direction of the earth, there are Ursa major and Ursa minor in the northern sky, and Orion, Sirius and Aquarius in the southern sky.

In fact, this is a very narrow spatial orientation, which has no meaning in the vast universe.

Even in a very small solar system, we have not yet determined how many planets there are, which is temporarily defined as nine planets orbiting the sun. It should be noted that not long ago, we were still calling for eight planets, but now scientists have found that Pluto's trajectory is still biased, which means that the tenth giant planet must exist and has not been observed.

Assuming that the trajectories of the nine planets are regarded as a plane, how high and how long the solar system is, there is still no conclusion. Even whether stars move around galaxies has been proved.

Or there are no static galaxies in the universe, and there is no exact space. There is no fixed planet, no fixed position.

In short, human beings know little about the universe, but one thing is certain: all directions of the earth are the Milky Way, and there are countless galaxies in all directions of the Milky Way. In the universe, no matter where you are, no matter which direction you look, there are endless emptiness and countless stars.