There are many ways to prove spherical earth. Let me say an example: Take a look at a ship going out. If the earth is flat, you will notice that the small ship gradually disappears and disappears. Listen to it seems reasonable, but take a closer look. When watching a ship sailing, the ship will disappear from view, but first, you will see the hull of the ship disappear first, then gradually to the sad column, and finally the turn. lost completely. From this it can be said that the Earth must be "curved" a little, this phenomenon can happen. Right?