Demonstration Using a Glass of Water at the Tiangong Space Station

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Chinese astronauts performed science demonstrations at the Tiangong Space Station. One of these demonstrations involves a glass of water and a ping-pong ball. Flat-Earthers saw a photo of the glass of water from the set, and they used it to discredit spaceflight. They claim that if it is really in space, then the water and glass should float.

In reality, the glass was attached to the table, and the water stayed in the glass because of adhesion between the glass and water, not gravity. The surface of the water also bulges and is not level with the glass or the table, as expected in a microgravity environment.

The astronauts used the set to demonstrate buoyancy in space. They pushed a ping-pong ball into the water, and it did not float like on Earth. At the end of the demonstration, they detached the glass from the table and floated it with the water & the ping-pong ball still inside it, and everything behaved as it should in a microgravity environment.

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Shadow of Flame

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A flame can produce a shadow if the other light source is much brighter, then refracted by the temperature difference, or the flame produces soot, steam, or other combustion products.

Flat-Earthers discovered images of flames not casting a shadow, & when they saw in a photo that a rocket’s exhaust casted a shadow, they used it as “evidence” it was faked. In reality, a flame can produce a shadow under the right conditions. Rockets have opaque combustion products, & in daylight, are lit by the very bright sun.

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Tiangong Space Station’s Panoramic Video

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The Tiangong space station is equipped with a panoramic camera. It produces panoramic video in the equirectangular projection. It has a field of view of more than 180° & can see “behind” the camera. The image is unlike what our eyes see.

Flat-Earthers noticed the “funny” shape of the Earth from the Tiangong’s live stream & use it to discredit the mission. In reality, the image is panoramic. It shows the view behind the camera & cannot be compared to what our eyes would see.

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Going Beyond Low Earth Orbit (LEO)

As of 2021, the Apollo missions are the only time humans travel farther than Low Earth Orbit (LEO). After the equipment used by the Apollo missions was decommissioned, no humans had the capability to go beyond LEO, and it remains the case in 2021.

Space agencies said we cannot go beyond LEO and are currently developing the capability. Flat-Earthers interpret it as “proof” we never went to the Moon. In reality, these space agencies were describing the present situation; it does not mean we never previously achieved beyond-LEO human spaceflight. As of 2021, we have the means to deliver beyond LEO, but not humans yet again.

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How Satellites Can Orbit and Stay Up There

Earth’s gravity pulls things toward Earth. Satellites can stay up there because they are orbiting. They are moving at the right speed and right direction to counter the pull of gravity.

Flat-Earthers claim that satellites should fall down if gravity pulls toward Earth. In reality, we do not just launch satellites to space. We also give them the correct speed & direction, so they neither fall toward Earth nor keep going farther away.

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GoFast Rocket and Yo-Yo De-Spin Mechanism

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The GoFast rocket is considered to be the first amateur rocket to reach space, beyond the Kármán line. The rocket was spin-stabilized through ascent. After reaching a certain altitude, it used the yo-yo de-spin mechanism to reduce the spin rate.

Flat-Earthers noticed the rocket’s spinning motion suddenly slowed, and they used it to “prove” the rocket “hit a barrier” up there. In reality, a yo-yo de-spin mechanism was deployed to slow the spin, but the rocket was still going up for some time afterward. — Hitting a barrier would have destroyed the rocket.

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First Image of Earth From Space Taken By a V-2 Rocket

The first image of Earth from space was taken by the V-2 No. 13 rocket in 1946 using the DeFry 35mm movie film camera and a 50mm lens attached to the rocket. The camera had a relatively narrow field of view. As a result, Earth’s curvature is only very slightly visible.

Flat-Earthers claim the flat appearance in the photo “proves” a flat Earth. In reality, 1. by careful examination, we can see the curve, 2. the camera has a narrow field of view, reducing the visible curvature, 3. the photo shown by flat-Earthers is usually a cropped version, further reducing the visible curve, and 4. the photo matches the expected curvature according to simulation.

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Image of William Shatner Wearing the Same Jacket as Jeff Bezos

In 2021, William Shatner becomes the oldest person to travel to space after he went up with Blue Origin. Conspiracy theorists noticed a Photoshopped image of Shatner wearing a Blue Origin Jacket. And they use the image to discredit spaceflight.

Conspiracy theorists —including flat-Earthers— were quick to notice the Photoshop job, yet unable to notice the glaring fact that Blue Origin had nothing to do with it.

Even if they did it, it does not “prove” anything. This incident, however, serves to demonstrate the inability of conspiracy theorists to use their critical thinking skills.

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Sun Outage

A Sun outage is a disruption of geostationary satellite signal caused by interference of the sun when it falls directly behind a satellite with which a receiver is communicating. Sun outages occur around the March equinox and September equinox.

Flat-Earthers fail to understand how the schedule of a Sun outage depends on the satellite and the receiver’s location. And they use it to discredit the fact. In reality, it is not difficult to visualize how a Sun outage occurs, and it will be consistent with the expectation.

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Neutral Buoyancy Pool for Astronaut Training

A neutral buoyancy pool is a pool of water in which neutral buoyancy is used to train astronauts for the difficult task of working outside a spacecraft in a weightless environment. Some of these pools contain full-scale mock-ups of ISS modules and other spacecraft.

Flat-Earthers discovered videos of astronauts in a pool of water, and they jumped to the conclusion that it is how they faked videos of astronauts in space. In reality, these are videos of astronauts in a neutral buoyancy pool, in training for their upcoming mission to space.

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Sound in Space

Sound wave requires medium to propagate. There is no air in space, and therefore, sound cannot travel over space. However, in some cases, sound and vibration can still travel over solid objects —like spacecraft or spacesuits— that exist in space.

In some videos taken in space, things that occur in a vacuum can be heard, and flat-Earthers use it to discredit spaceflight. In reality, 1. sound can still travel over solid spacesuits and spacecraft, 2. vibrations can cause noise in microphones, 3. there is air inside spacesuits and many spacecraft, 4. the sound was heard over the radio communication system, and not directly over space.

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Orbit of DSCOVR Satellite

The DSCOVR satellite orbits around the Lagrangian point L1 between the Sun and Earth. We can say the DSCOVR satellite lies between the Sun and Earth, but it is not exactly between them.

Flat-Earthers discovered images taken by the DSCOVR satellite showing the Moon in front of Earth and a solar eclipse shadow on Earth’s surface. Then they concluded it should be impossible if DSCOVR is really between the Sun and Earth. In reality, the DSCOVR satellite is not exactly between the Sun and Earth. It orbits a point between the Sun and Earth.

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Seeing Stars in Space

Stars are dim. We can only see them if our eyes are adapted for low light. Astronauts in space can see the stars when the sun is blocked from view and avoid seeing any large sunlit objects.

Some astronauts said they did not notice the stars, but others claim they could see them. Flat-Earthers use the conflicting statements to discredit spaceflight. In reality, sometimes astronauts can see the stars, and sometimes cannot, just like us on the ground, depending on the situation.

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Making-of or Behind-the-Scenes

In cinema, a making-of or behind-the-scenes is a documentary featuring the production of a film. It describes how the scenes in a movie were created. Some trolls took footage from the behind-the-scenes of various space movies and present them to flat-Earthers as though it is how space agencies “faked” their videos.

Flat-Earthers fail to realize that these footage were just behind-the-scenes of space movies and unrelated to the actual space footage from space agencies. These spread as hoaxes in flat-Earth circles.

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Frame of Reference

A frame of reference consists of an abstract coordinate system and physical reference points that uniquely fix the coordinate system and standardize measurements. Speed or velocity is relative to a specific frame of reference. It is possible that two speeds/velocities are measured relative to a different frame of reference and thus cannot be directly compared.

Flat-Earthers like to compare two different speed measurements like an airplane moving at 900 km/h (560 mph) and Earth’s surface near the equator at 1674 km/h (1040 mph). They would conclude the airplane should not be able to catch up with Earth’s surface and would not land if the Earth is rotating. In reality, both the speeds are measured relative to a different frame of reference, and therefore, cannot be compared directly.

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Fallacy of Appeal to Worse Problems / Relative Privation

The fallacy of appeal to worse problems (or relative privation) occurs when someone argues that efforts spent to solve a specific problem are a waste by pointing out that there are bigger problems that need to be solved.

Space research is a common target of appeal to worse problems. Flat-Earthers use it to discredit space research and to make people emotional. In reality, it is possible to care about multiple problems simultaneously, and solving the supposed smaller problems does not mean the bigger one is considered unimportant.

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How Rocket Engines Work in A Vacuum

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Rocket engines produce thrust by releasing mass rearward at a very high speed according to Newton’s third law, not unlike how discharging a fire extinguisher pushes us backward.

Flat-Earthers claim that rocket engines cannot possibly work in space because space if vacuum and there is no air to push against. In reality, it is possible to produce thrust in a vacuum by releasing mass —that we call “propellants”— rearward at a very high speed.

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Cloud Movements Seen From Space

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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The Myth We Knew Earth is a Sphere From the First Spaceflight

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.

Images of the Apollo Moon Landing Sites Taken By LRO

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.

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