Suppose you were to meet someone who makes this claim. Nevertheless, there are some people today (including a few celebrities) who have tried to claim that Earth is flat. If true, this implies that the people who sent Columbus on his trip had a better idea of what he would find than Columbus did himself.Īs we have discussed, humans have known Earth to be round for at least about 2,700 years. As a side note, some historians suspect that Columbus ultimately received funding for his voyage from the Spanish only because Spanish scholars had heard stories of Viking voyages to the Americas a few hundred years earlier. Columbus was the one who was wrong, and his planned voyage to Asia would certainly have ended in disaster if the Americas hadn’t stood in his way. Columbus argued that the distance was actually much shorter. Using estimates of Earth’s size (going back to measurements like those of Eratosthenes discussed in the Do the Math box above) and of the size of the Eurasian continent, most scholars concluded that the distance from Europe to Asia by sea was too far for the small sailing vessels of the time (that is, they could not carry enough food and supplies). Indeed, historical evidence indicates that even the general public in Europe knew that Earth was round during Columbus’s time, and that the scholarly debate over whether Columbus’s proposed voyage was doable revolved instead around the question of the distance from Europe to Asia. Step 6 – Use these additional observations to discuss evidence and reasoning in support of the following claim: “The fact that shadows have different lengths in different cities at the same time proves that Earth cannot be flat.”Ĭonnections-History Columbus and the round EarthĪ widespread myth gives credit to Christopher Columbus for learning that Earth is round, but knowledge of Earth’s shape predated Columbus by at least about 2,000 years. Do the two sticks still cast shadows of the same length?

Step 5 – Bend the paper plate slightly, as though modeling the curvature of the Earth between two cities, then again observe the shadows cast by the popsicle sticks. Use the observations you have made so far to discuss evidence and reasoning in support of the following:Ĭlaim: “If Earth were flat, then at any particular time, the shadows cast by identical sticks in different cities would all have the same length.”

Step 4 – You can think of the flat plate as representing what Earth would look like if it were flat, and the two popsicle sticks as the locations of two cities on a flat Earth the light source represents the Sun. Can you find an orientation in which neither popsicle stick casts a shadow? Explore how the shadows of the two popsicle sticks compare when you tilt the plate to different angles relative to the light source. Step 3 – Have one team member hold the plate vertically in front of the lightbulb or flashlight, while the other team members observe whether there are any shadows cast by the popsicle sticks. You can use tape to secure your popsicle sticks to the plate so that they stay pointed straight out. Step 2 – Make a small hole on each mark and push a popsicle stick into each hole, so that the popsicle sticks are pointing straight out of the plate (that is, perpendicular to the plate). Step 1 – Mark two places directly across from each other on the paper plate, near to the edge, but not too close. Group Activity How Shadow Comparisons Prove Earth is Roundīreak up into teams of two or three to demonstrate how the length of shadows depends on the curvature of the Earth.

Flat earther perfect horizon