Evidence why the earth is round

One of the major problems is the size and brightness of the Sun. In the flat-Earth model this varies by more than a factor of two from sunrise to midday, something we obviously do not see. The night sky also differs. In the northern hemisphere we see constellations rising in the east and arcing across the sky but in the flat-Earth model they would just circle at a constant height. I no longer feel that way. But Effingham, who has also interacted with flat-Earthers on Facebook, wonders if physics is the place to start combating these conspiracy-based ideas.

Effingham also tries to point out their inconsistencies. He was simply told that planes can fly on one tank of fuel and refuelling planes could just be a giant hoax to stop us realizing that the Earth is flat. Landrum agrees the underlying problem is one of trust rather than physics. That may seem like an excruciatingly painful process, but a necessary one, for people to gain trust in science as an institution again.

A level of sustained personal engagement can change minds. He was appointed by Donald Trump in and was known to have disputed climate change. The difference was that the evidence was presented to him by scientists he had grown to trust. Oddly, Landrum says that many flat-Earthers may distrust scientists, but they are not against the scientific method. Close search menu Submit search Type to search. Topics Astronomy and space Atomic and molecular Biophysics and bioengineering Condensed matter Culture, history and society Environment and energy Instrumentation and measurement Materials Mathematics and computation Medical physics Optics and photonics Particle and nuclear Quantum.

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If Earth were flat, the sun would not be visible at any elevation once it had set. Because Earth is round, the sun will come back into your line of sight. If you don't have a hill, you could even try lying on your stomach to watch the sunset and then standing up to get a higher line of sight. Pick two locations that are some distance apart at least a couple hundred miles from each other and on the same meridian.

Grab two sticks or dowels or other objects of equal length, two tape measures, and a friend. For accuracy, you should both take your measurements at the same time of day. On a flat Earth, the shadow that is cast by each would be of the same length. However, if you and your friend compare notes, you'll find that one shadow was longer than the other. That's because, due to the curvature of Earth, the sun will hit one part of Earth at one angle and another part of Earth at a different angle even at the same time of day.

This experiment has been around since about B. Eratosthenes had learned of a well in Syene where once a year on the summer solstice, the sun would illuminate the entire bottom of the well and tall buildings and other objects would not cast a shadow. However, he noticed that shadows were being cast on the summer solstice in Alexandria, so he measured the angle of the shadow and found it to be an angle of about 7.

Sometimes, seeing is believing, and one's own research can be the best evidence, whether that's taking the time to do your own investigating or simply searching for the results of others who have run their own experiments. Correction: A previous version of this article mistakenly referenced solar eclipses, where the Moon passes between Earth and the Sun, instead of lunar eclipses, where the Earth passes between the Moon and Sun. The text has been updated.

The author apologizes for the error. An English major at the University of Southern Maine, Erik's strong background in writing and love of American football led him to pursue a career in sports journalism out of college. His book, Bill Belichick vs. Tired of chasing leads and digging for quotes from people who didn't really want to give them, Erik joined the Cell Press family in and hasn't looked back. Filed to Pop sci.

Cell Mentor—an online resource from Cell Press and Cell Signaling Technology—empowers early-career researchers with career insights, publishing advice, and techniques on experimental processes and procedures. Search ». Watch a ship sail off to sea Without being in the sky, it is impossible to see the curvature of the Earth.

Watch a lunar eclipse Solar eclipses get all the attention, but if you are able to catch a glimpse of a lunar eclipse, you can see evidence that the Earth is, indeed, round.

About Cell Mentor. Subscribe to Cell Mentor. If you'd like to prove to yourself that perspective isn't the reason for boats disappearing hull-first and returning mast-first, bring a telescope or binoculars on your trip to the harbor.

Even with vision enhancement, the ship will still dip below the curve of the Earth. Greek philosopher Aristotle figured out this one in B. Different constellations are visible from different latitudes. Probably the two most striking examples are the Big Dipper and the Southern Cross.

The Big Dipper, a set of seven stars that looks like a ladle, is always visible at latitudes of 41 degrees North or higher. Below 25 degrees South, you can't see it at all. And in northern Australia, just north of that latitude, the Big Dipper just barely squeaks above the horizon. Meanwhile, in the Southern Hemisphere, there's the Southern Cross, a bright four-star arrangement.

That constellation isn't visible until you travel as far south as the Florida Keys in the Northern Hemisphere. These different stellar views make sense if you imagine the Earth as a globe, so that looking "up" really means looking toward a different sliver of space from the Southern or Northern hemisphere.

Aristotle also bolstered his belief in a round Earth with the observation that during lunar eclipses, the Earth's shadow on the face of the sun is curved. Since this curved shape exists during all lunar eclipses, despite the fact that Earth is rotating, Aristotle correctly intuited from this curved shadow that the Earth is curvy all around — in other words, a sphere.

For that matter, solar eclipses also tend to bolster the idea that the planets, moons and stars are a bunch of roundish objects orbiting each other. If the Earth is a disk and the stars and planets a bunch of small, nearby objects hovering in a dome above the surface, as many flat-Earthers believe, the total solar eclipse that crossed North America in August becomes very difficult to explain.

This is another one of those self-evident things: You can see farther if you go higher. If the Earth was flat, you'd be able to see the same distance no matter your elevation.

Think about it: Your eye can detect a bright object, like the Andromeda galaxy, from 2.