Clouds are moved by the wind. The average wind speed at the altitude of clouds is only about 18–70 km/h, relatively slow compared to the size of visible Earth’s surface from space.
Flat-Earthers use the lack of an apparent cloud movement to discredit videos taken from space. In reality, the clouds are moving far too slowly to appear moving in videos taken from space. To observe the cloud’s motion, we need to speed up the video.
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Flat-Earthers like to dismiss any evidence of spherical Earth by mentioning that we never went to space to witness it ourselves. In reality, to go to space, we need to know Earth is a sphere in the first place and other related knowledge, like gravity.
We knew Earth is a sphere 23 centuries before the first spaceflight. And it is easy to verify Earth is a sphere from simple observations that anyone can do from Earth’s surface.
The Lunar Reconnaissance Orbiter (LRO) is a spacecraft orbiting the Moon. It is equipped with a high-resolution camera that has captured photographs of Apollo landing sites.
We often observe flat-Earthers demanding NASA to prove the Apollo missions with recent photos of the landing sites, and NASA has provided just that. However, this too will not be enough for them to accept that the Apollo missions did occur.
Continue reading “Images of the Apollo Moon Landing Sites Taken By LRO”
The fallacy of the single cause occurs when it is assumed that there is a single, simple cause of an outcome when in reality, it may have been caused by a number of only jointly sufficient causes.
If it is said that “A causes B,” it is rarely that B is caused only by A, but usually, there are other things that cause B simultaneously with A that are not explicitly mentioned. Assuming that only A causes B from the statement without further consideration is the single-cause fallacy.
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Newton’s cannonball was a thought experiment Isaac Newton used to explain the principle of orbital motion. It was the first explanation of an orbit and still the easiest to understand.
Newton visualizes a cannon on top of a very tall mountain where the air resistance is no longer a factor. As more charge is used with each cannon shot, the speed of the cannonball will be greater, and the cannonball will hit the ground farther and farther. Finally, at a certain speed, it will not hit the ground at all. It will fall toward the spherical Earth just as fast as the Earth curves away from it. In the absence of drag from the atmosphere, it will continue forever in orbit around the Earth.
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The Apollo Lunar Module needed to be as light as possible. It would also operate only in a vacuum and did not have to be sturdy or aerodynamic. To reduce weight, its hull was covered with various insulation blankets instead of rigid heat shields.
Flat-Earthers often ridicule the shape of the lunar module of being flimsy. In reality, there is no requirement to look pretty. The flimsy-looking things are just the insulation blankets. The actual hull underneath them provides structural support.
Continue reading “Apollo Lunar Module Insulation Blankets”
Many space missions use animations to visualize the state of the missions because it is impossible to record a video of the event. Spacecrafts continuously send telemetry data to Earth informing the status of their mission, and from the data, an animation can be constructed to illustrate the spacecraft’s current situation.
Flat-Earthers accuse that the animations are “proof” that the missions are faked. In reality, the animations are faithful depictions of the missions and are made to visualize the real state of the mission. Animations are used because it is not viable to send another spacecraft only to record a video of the mission. Furthermore, in the cases where the video is available, it is still too difficult for these flat-Earthers to accept reality.
The International Space Station (ISS) was not constructed overnight. It is built gradually, and new components are still arriving after more than 20 years since it was first launched.
The ISS is one of humankind’s greatest achievements, but there is no video showing its construction from start to finish. Flat-Earthers use the fact to “disprove” the existence of the ISS. In reality, the ISS was constructed gradually in years. There is no such video the same way there is none for New York City, for example. It does not mean New York City does not exist. On the other hand, we can find plenty of videos showing the assembly of its specific modules on the Internet. Continue reading “ISS Construction Video”
It is possible to fly to space as a tourist as long as we are willing to pay a lot of money. There have been seven persons who went to space and paid the trip from their own pockets.
Flat-Earthers claim if the first human spaceflight was more than half a century ago, there should be space tourism by now. In reality, there were already several cases of space tourism, even if it is still beyond the reach of most people today.
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In orbit, objects are weightless because both the objects and the spacecraft have the same speed and direction, and both are affected by the same gravitational influence. We use the spacecraft as the frame of reference. Because the objects are not in motion relative to the spacecraft, they appear to float.
In Earth orbit, the objects are still affected by Earth’s gravity, but yet they float. Flat-Earthers use it to disprove spaceflight. In reality, the objects float because we are using the spacecraft as the frame of reference, which is also moving by the same amount and is affected by the same gravity as the objects themselves.
Continue reading “Weightlessness, Free Fall, and Microgravity”
Richard Garriott is a video-game developer and entrepreneur who is also an avid magician. In October 2008, he flew to the ISS onboard a Soyuz rocket as a private astronaut. During his time on the ISS, he performed several magic tricks.
One of his magic tricks involves a hammer that floats and a card that seems to fall as if it is pulled down by gravity. Flat-Earthers were unaware it was a mere magic trick and wrongly assume it demonstrates things are falling in the ISS, despite other objects in the scene that float.
Continue reading “Richard Garriott’s “Pocket of Gravity” Magic Trick”
After the Apollo moon landings, we continue launching missions to the moon, but with uncrewed spacecraft. The Apollo program was not entirely a scientific mission. It also served as a political mission due to the Cold War. We can research a lot of things about the moon without risking human lives by sending them to the moon.
Flat-Earthers claim that there have not been any missions to the moon after the Apollo missions, and they conclude that the Apollo missions were fabricated. In reality, we continue sending spacecraft to the moon to this day.
Continue reading “Missions to the Moon, Post-Apollo”
Flat-Earthers often challenge us to provide a video of a rocket launch that was taken from the rocket itself, without interruption from launch to reaching space, as if it would convince them to accept that it is real and the Earth is a sphere.
The launch video of the 2001 Mars Odyssey mission easily fulfills their demand. But whether they can manage to accept the reality that Earth is a sphere is entirely another matter.
Continue reading “2001 Mars Odyssey Launch Video”
Mars One was a questionable organization that received investments by claiming it would use it to land humans on Mars. It was not a credible company, and many consider it was a scam to take money from investors and participants.
Mars One had a lot of media attention, but it was dissolved without any achievement. Flat-Earthers use it to discredit space travel. In reality, the company was not credible in the first place, and practically nobody in the aerospace industry thought Mars One was serious in their objective.
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An airplane relies on the lift from its wings, which depends on the airplane’s speed and the air density. As a result, a cruising airplane will fly at a constant altitude, following the curvature of the Earth.
Flat-Earthers claim if Earth is a sphere, an airplane has to dip its nose down periodically, or it would fly into space. In reality, an aircraft will follow Earth’s curvature and is unable to fly to space even if the pilot deliberately attempts to do that
Continue reading “Airplanes Will Never Fly Into Space”
In the video of the CRS-19 mission of the SpaceX Falcon9 rocket, flat-Earthers noticed something is moving near the exhaust of the second stage rocket. Creatively, they interpreted it as a “mouse, ” and then use it to discredit spaceflight and the people involved in it.
In reality, it was merely crystallized waste from the rocket engine. To know this, we only need to see the part of the video after the one cherry-picked by flat-Earthers. The “mouse” slowly disappeared by evaporation.
Continue reading ““Mouse” on a SpaceX Falcon9 Rocket Launch”
Rocket launches have a curved trajectory because their objective is not only to reach space but also to enter Earth orbit. To achieve it, a spacecraft needs to gain a sufficient horizontal speed, parallel to Earth’s surface.
Flat-Earthers claim the curved appearance of a rocket launch trajectory “proves” rockets never reach space. In reality, it is caused by the motion of the rocket parallel to Earth’s surface, perspective effect, and the curvature of the Earth.
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Rockets consist of several stages. Two or more smaller rockets are combined into a single rocket. They are ignited in order; when an earlier stage runs out of propellants, it is jettisoned to reduce the load for the rest of the rocket.
Flat-Earthers noticed videos of rockets being recovered from the ocean and use them as “evidence” rockets never went to space. In reality, these are the jettisoned earlier stages of the rockets. The latter stages do reach space.
Continue reading “Rocket Staging”
If a satellite is placed in an orbit 35786 km above the equator, it will be in motion at the same speed as the Earth’s rotation. As a result, the satellite will appear practically motionless from an observer on Earth’s surface. Many communication satellites are in this orbit so that a satellite receiver does not need to track the satellite continuously.
Flat-Earthers often take the fact that satellites are in motion, and most satellite dishes have a fixed direction as ‘proof’ the receivers cannot be pointing to satellites. In reality, it is possible to place a satellite in a geostationary orbit to make it appear in a fixed position in the sky relative to an observer on Earth.
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In 2019, scientists discovered that Earth’s atmosphere consists of a hydrogen cloud called the geocorona that extends to the Moon and beyond. Its density is minuscule, practically vacuum, and does not affect space travel.
Flat-Earthers claim this is an “admission” as the Moon has always been “inside the dome” in their flat Earth model. In reality, the discovery does not change much about what we already know.
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