Spherical Earth - Summary of Evidence For A Spherical Earth

Summary of Evidence For A Spherical Earth

These are given in an order which approximates how they were observed historically:

1. When at sea it is possible to see high mountains or elevated lights in the distance before lower lying ground and the masts of boats before the hull. It is also possible to see further by climbing higher in the ship, or, when on land, on high cliffs.
2. The sun is lower in the sky as you travel north, but stars such as Polaris, the north star, are higher in the sky. Other bright stars such as Canopus, visible in Egypt, disappear from the sky.
3. The length of daylight varies more between summer and winter the farther you are from the equator.
4. The earth throws a circular shadow on the moon during a lunar eclipse.
5. The times reported for lunar eclipses (which are seen simultaneously) are many hours later in the east (e.g. India) than in the west (e.g. Europe). Local times are confirmed later by travel using chronometers and telegraphic communication.
6. When you travel far south, to Ethiopia or India, the sun throws a shadow south at certain times of the year. Even farther (e.g. Argentina) and the shadow is always in the south.
7. It is possible to circumnavigate the world; that is, to travel around the world and return to where you started.
8. Travelers who circumnavigate the earth observe the gain or loss of a day relative to those who did not. See also International Date Line.
9. An artificial satellite can circle the earth continuously and even be geostationary.
10. The earth appears as a disc on photographs taken from space, regardless of the vantage point.

Several of these arguments have alternative explanations by themselves. e.g. the shadow thrown by a lunar eclipse could be caused by a disk-shaped earth. Similarly the north-south movement of stars in the sky with travel could mean they are much closer to earth. However, the arguments strengthen each together.