"An" answer isn't necessarily the "correct" answer. For thousands of years people saw the sun rise in the east and set in the west and the answer they came up with was that the sun travelled around the Earth. They also saw ships disappear over the horizon and assumed that the Earth was flat and when ships disappeared it was because they were dropping off the edge. Both of these "answers" were (for the time and science (including exploration)) extremely valid answers. They were logical and they explained the phenomena that people experienced. They were also 100% wrong.
A common falacy is that mankind used to think the earth was flat, this is not true.
four corners of the Earth elaborated (round Earth). Even the Bible states the earth is a circle:
Job 26:10
10 "He has inscribed a circle on the surface of the waters,
At the boundary of light and darkness.
NAS
Proverbs 8:27
27 "When He established the heavens, I was there,
When He inscribed a circle on the face of the deep,
NAS
Greek philosophers (the forefathers of science) did not view the earth as the center of the universe:
Hipparchus, according to Ptolemy, considered that the Earth is not the center of the circular orbit of the Sun. From his observations Hipparchus used epicycles and deferents to describe the elliptic motion of the planets and the moon, an idea that later Ptolemy used in his model. Hipparchus measurements were so accurate that he knew that his model is only an approximation especially for the complicated motion of the moon.
http://www.mlahanas.de/Greeks/Hipparchus.htm
As to showing you a prophecy that can be dated as yet future, read Revelation. An interesting aspect of history that is seldom shared in schools is that Alexander the Great was impressed when Hebrew priests were able to show him that he is mentioned in prophecy.
Daniel 2:28-35
28 "However, there is a God in heaven who reveals mysteries, and He has made known to King Nebuchadnezzar what will take place in the latter days. This was your dream and the visions in your mind while on your bed. 29 "As for you, O king, while on your bed your thoughts turned to what would take place in the future; and He who reveals mysteries has made known to you what will take place. 30 "But as for me, this mystery has not been revealed to me for any wisdom residing in me more than in any other living man, but for the purpose of making the interpretation known to the king, and that you may understand the thoughts of your mind.
31 "You, O king, were looking and behold, there was a single great statue; that statue, which was large and of extraordinary splendor, was standing in front of you, and its appearance was awesome. 32 "The head of that statue was made of fine gold, its breast and its arms of silver, its belly and its thighs of bronze, 33 its legs of iron, its feet partly of iron and partly of clay. 34 "You continued looking until a stone was cut out without hands, and it struck the statue on its feet of iron and clay, and crushed them. 35 "Then the iron, the clay, the bronze, the silver and the gold were crushed all at the same time, and became like chaff from the summer threshing floors; and the wind carried them away so that not a trace of them was found. But the stone that struck the statue became a great mountain and filled the whole earth. NAS
Alexander corresponds to the bronze section of the statue.