### Curved Rocket Trajectory

Rockets follow a curved trajectory when going into space because their objective is not only to reach space, but also to enter Earth orbit. In Earth orbit, rockets have enough speed to counter Earth’s gravity and do not require a lot of energy to stay up there. To enter Earth orbit, a rocket needs to attain a high enough horizontal speed.

Flat-Earthers claim the curved trajectory of any rocket launch tells us no rocket has ever reached space. They are wrong. The curved trajectory is a way for rockets to enter Earth orbit.

### Midnight Sun In Both Polar Regions: Proof That the Earth is Round

Midnight Sun is a natural phenomenon when the Sun remains visible at midnight. This phenomenon occurs in the summer months in the north of Arctic Circle, and south of the Antarctic Circle.

The apparent motion of the Sun in both polar regions is different. In the north polar region, the Sun moves from left to right. On the other hand, in Antarctica, the Sun moves from right to left. It is not difficult to imagine that we all reside on a rotating sphere. There’s just no other explanation.

### The False Analogy of a Spinning Tennis Ball

The mass of the Earth exerts the gravitational acceleration of about 9.79 m/s² to everything on Earth’s surface toward the center of the Earth. On the other hand, the rotational motion of the Earth generates the centrifugal acceleration of about 0.03 m/s² away from the Earth. The net acceleration is about 9.79 m/s² toward the center of the Earth. That is why everything on Earth’s surface stays on the surface, not flying away to space.

Flat-Earthers often make a false comparison using a wet spinning ball. Water on the surface of a wet spinning ball does not stick to the ball; but the Earth is also round, wet and spins, yet everything stays on the surface. Then they make the erroneous conclusion that the Earth cannot be a spinning ball.

### The Direction of Sunrise and Sunset

We know for granted that during an equinox, the Sun rises from the east and sets in the west. Such facts are undisputed and have been verified through centuries of observation.

The flat-Earth model, however, is unable to accommodate this simple fact. And thus, it is not hard to conclude that the flat-Earth model does not represent reality.

### Space Flight and the Temperature in the Thermosphere

The thermosphere is a layer of the Earth’s atmosphere from about 95 km­ to 600 km. It is named ‘thermosphere’ because its temperature increases with altitude. The temperature in the thermosphere can reach 2500°C. However, air density in the thermosphere is very low to the point that heat conduction practically does not occur. Objects in the thermosphere will feel cold.

Flat-Earthers discovered that the temperature in the thermosphere could reach 2500°C. They are happy to ignore the other information which usually accompanies it: the air density up there is also far lower.

### Sunset at Burj Khalifa

Having the total height of about 830m, Burj Khalifa is the tallest building in the world. It is so tall that we can observe the sunset at the base of the building, then rush to the upper floors and watch the same sunset again for the second time on the same day.

This phenomenon can only happen if the Earth is a sphere. On a higher position, we will observe the sunset later than when we are closer to the ground.

### Consistency of Photos of the Earth

Every time NASA (or anyone else) releases a picture of the Earth from space; flat-earthers would compare it to another image of the Earth. Every photo is going to be different from another, but flat-earthers love to use this fact as a ‘proof’ that these photos are results of image manipulation, and that we are being deceived somehow.

### The Philosophy of CGI

When a photo of spherical Earth is pointed out to flat-earthers, they will dismiss it as CGI in the blink of an eye; even if they haven’t done any analysis at all. They do this because their belief in flat-Earth is not evidence-based, and any evidence contrary to their beliefs needs to be invalidated no matter how.

They are so used to doing it, and sometimes they become confused by it themselves, to the point that they would take the slightest hint of digital manipulation of any picture of the Earth as evidence of the flat Earth.

### Google Maps, GPS and Cellular Signal Reception

“If we are in a location without a cellular signal, then GPS in our phones will not function perfectly. Conclusion: GPS utilizes signal from cell towers, not satellites.”

Some flat-earthers made the above conclusion. What they meant by ‘GPS’ is surely the app Google Maps or another similar app.

### Isaac Newton and The Law of Universal Gravitation

Isaac Newton formulated the law of universal gravitation which explained the motion of all celestial bodies in space known at his time. Also, he demonstrated that it is the same law that is causing everyday objects to fall to Earth.

Newton wrote that he had not been able to discover the reason for the phenomenon of gravity. Flat-Earthers use this as “proof” that he lied and he did not know anything about gravity, and that gravity was a mere fabrication. They are wrong. Gravity adequately explained the motion of all celestial bodies and the fact that everyday objects are falling to Earth. Newton simply did not know what is causing it.

### Psychological Projection

Why do we believe in conspiracy theories? According to research, one reason is the so-called ‘psychological projection’.

‘Psychological projection’ is a phenomenon where someone denies their attitude or traits and assumes instead that others are doing so. They see their negative qualities in others, even when the negative characteristics are not present in the others being accused.

### Polaris – The North Star

To most flat-earthers, the Earth is stationary. Stars are light sources attached to the firmament (for some mysterious reason), and they rotate around Polaris (again, for some mysterious reason).

However, they are missing the fact that Polaris is never visible from the southern hemisphere. And furthermore, the southern stars also rotate around the south celestial pole.

### Flight Altitude and Sphericity of the Earth

So, there was a flat-earther who took a spirit level on a flight. His intention was to determine whether the plane periodically adjust its angle in order to make it level in relation to the surface of the Earth. According to him, if the Earth were really spherical, then the plane would need to make these periodic adjustments; otherwise it would fly away straight into space!

His video became viral, and predictably, the plane did not make these periodic adjustments. The conclusion, surely, is not that the Earth is flat. The following are some explanations why the plane doesn’t have to make those periodic adjustments, and still reaches its destination.

### Emergency Landings and Flight Route

We cannot take a straight line between two locations on a map and consider that line the shortest distance between the two locations. With a very short distance —like within a city— it wouldn’t usually matter. But for long-haul flights across continents, then it would matter a lot.

Flat-Earthers are known to use this mistake —whether deliberately or not— as a ‘proof’ that the Earth is flat. A common case they would bring is emergency landings.

### Missions to the Moon, Post-Apollo

“After Apollo, there was never another mission to the Moon. It means that the Apollo missions were faked, and we never actually went to the Moon.”

That’s how flat-earth believers think about Apollo missions, and missions to the Moon in general. Because they think there was never any missions to the Moon after Apollo, then they conclude that the Apollo mission was staged, and never happened.

Is that so? Apparently not. Although by the time this article was written, Apollo is still the only mission to the Moon that brought humans up there, doesn’t mean there are no missions to the Moon after that.

### Fisheye Lenses and Earth Curvature

A good majority of pictures of Earth taken from space are being dismissed by flat-earthers merely because they are made using fish-eye lenses. They believe any curvature of Earth shown in those pictures is the result of the fisheye effect, and thus, cannot be used as evidence of Earth’s curvature. They even take a step further and assume a fish-eye lens is deliberately used to take every picture of the Earth taken from a high altitude so that they would have a curvature in it.

These claims are, of course, ungrounded. In some cases, we can conclude the curvature is there, even when a fish-eye lens is being used. We can use this useful property of any photographic lens:

A straight line will appear straight as long as it crosses the center point of the image.

### Admiral Byrd: “An Area As Big As The United States on the Other Side of the South Pole”

According most flat earthers, there’s no such thing as the continent of Antarctica. In their imagination, Antarctica is not a continent, but  a long ice wall enclosing the Earth. Without having anything to prove that assumption, they look anywhere for any quote they can mine and stumbled into this quote by Admiral Byrd:

“Strangely enough, there is left in the world today, an area as big as the United States, that’s never been seen by a human being. And that’s beyond the pole, on the other side of the south pole from Little America.”

### So, Where’s the Curvature?

A human eye can only visually perceive the curvature of the Earth if we are at a considerable altitude from the surface, which is still beyond the reach of most humans today. A commercial jet airliner is the highest position realistically attainable by most humans today. At such altitude, we can only perceive very slight curvature, and only in an ideal condition.

The basis of flat-Earthers’ belief is that the horizon appears flat. They would say if we cannot see the curvature, then there’s no curvature, and thus, the Earth is flat. They are wrong. Most of us these days cannot travel high enough to see the curve.  The best we can do these days is going on board a commercial jet airliner, which can only go about 11-15 km up, only a fraction of the radius of the Earth.

### Welcome to FlatEarth.ws

Welcome to FlatEarth.ws! We operate an Indonesian Flat Earth debunking site BumiDatar.id since July 2017. Due to popular requests, we’ll be doing English version of our posts here. Stay tuned!