Although scientists have proven for 2,000 years that our planet is ball round, there is still a group of fanatics who claim that the earth is flat.
However, it takes no more than common sense to confirm that the earth is round. Here are five tangible proofs.
PROOF 1: The earth casts a round shadow on the moon
More than 2000 years ago, Aristotle discovered one of the most tangible proofs that our planet is spherical.
He noticed that the earth casts a round shadow on the moon during a lunar eclipse. During such an eclipse, the earth stands exactly between the sun and the moon, and the shadow betrays the shape of the globe.
If the earth were flat, a thin line of shadow would fall on the moon.
PROOF 2: You can look further as you get higher
Have you ever wondered why vantage points are always high? Even on boats where there are no trees and houses in the way?
The explanation for this is the round shape of the earth.
You can look further if you look higher, because the curvature of the earth provides a broader field of vision.© Moriel Schottlender
PROOF 3: Time zones exist© Shutterstock
If it is 12 o'clock in the afternoon on a winter day and the sun is at its highest, it is 6 o'clock in New York in the morning. The sun is not up yet.
In Sydney, at the same time, the clock shows 10 o'clock in the evening, and the sun has already set there.
Time zones exist because the sun illuminates one side of the earth at a time. If you hold a ball in front of a flashlight, you will see that the beam of light falls only on one side of the ball, while the other side remains dark.
According to the flat earthers the sun hangs above us and illuminates a small area at a time, but then we could see the light beam, although we were not directly under it.
The time zones thus illustrate that the earth is round and that it revolves around its own axis.
PROOF 4: You see ships looming on the horizon
If you've ever looked at the horizon from the beach, you may have noticed that ships don't suddenly appear on the horizon.
They would do that if the earth were flat.
In reality it looks like they are rising from the sea. That shows that you are looking at a portion of a curved surface, not at a flat surface.
PROOF 5: Photos from outer space show a round earth© NASA
Satellites, probes and space missions have been taking pictures of our planet for more than half a century.
All space photos show that the earth has a curved surface. Photographs taken from a sufficient distance show the home planet of humanity as a whole: a spherical earth.
Here you can take a look at the photo albums of the astronomers.