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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Earthrise is a photograph of Earth that was taken from lunar orbit by William Anders during the Apollo 8 mission. It was taken just after Earth rises from behind the Moon.

From Earth, the Moon always shows the same face, and from a location on the Moon facing Earth, it is impossible to see Earth rising. Flat-Earthers use it to reject the Earthrise as fake. In reality, the photo was not taken from the lunar surface, but from the lunar orbit. Apollo 8 did not even land on the Moon.

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“Moontruth” Prank Video

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In 2002, the advertising company Viral Factory filmed the “moontruth” video, which is a prank showing an “outtake” from the supposed faking of the “one small step” scene. The video shows “Neil Armstrong” (played by an actor) being interrupted by a falling studio light.

Flat-Earthers and other conspiracy theorists failed to realize that the video was just a viral prank video. It spreads in conspiracy theory circles as if it “proves” that the Apollo moon landing was faked.

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Communication Delays in Apollo Mission & The Direction of Conversation

Radio waves travel at the speed of light. In Apollo missions, after Houston said something, the response from the Moon arrived after 2½ seconds. But no delay occurred when Houston replied to the astronauts because the conversation was recorded on Earth.

Flat-Earthers use the lack of delay when Houston (and President Nixon) replied to the astronauts to discredit the Apollo missions. In reality, they cannot understand how the recording’s location and the direction of the conversation affected the delay in the recording.

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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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Fake Moon Rock That Turns Out to Be a Petrified Wood

The Apollo missions brought back moon rocks to Earth. Some of the moon rocks Apollo 11 and Apollo 17 brought back were gifted twice by President Nixon to 135 countries. In the Netherlands, both of these gifts are intact and preserved in a museum. However, there is another unrelated gift, in the form of petrified wood that was mistaken to be a moon rock for several years.

Flat-Earthers use the petrified wood incident to discredit the Apollo missions. In reality, the incident is not related to the two moon rocks that the United States officially gifted to the Netherlands, which are still displayed in Museum Boerhaave, Leiden.

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Five Photos of Neil Armstrong on the Moon

Neil Armstrong was the lead photographer on the Apollo 11 mission, and he could not be in the photos he was taking. Out of 1266 photos from the Apollo 11 mission, only five good photos of Neil were taken while Apollo 11 operated on the surface of the Moon.

Some memes humorously compare the total of five photos of Neil on the Moon to the number of selfies some ladies take in the bathroom. Flat-Earthers took them too seriously, and these became a hoax claiming that Apollo 11 brought back only five photos.

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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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The Missing Apollo 11 Telemetry Tapes

NASA lost the telemetry tapes containing the recording of the raw video data transmitted by the Apollo 11 mission. However, all the data was also safely recorded elsewhere.

Flat-Earthers make a big deal out of this incident to discredit the Apollo mission. In reality:

  1. The only lost data was the raw video before the conversion to NTSC for TV broadcasting.
  2. Only the raw data was lost, but there are other recordings of the same footage.
  3. Apollo missions other than Apollo 11 were not affected.
  4. There is no lost video that has never been seen.
  5. NASA discovered high-quality recordings of the same video.

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Apollo Lunar Module Insulation Blankets

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.

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Earthrise in President Nixon’s Oval Office

Earthrise is a photograph of Earth taken from lunar orbit during the Apollo 8 mission, seven months before the first Moon landing by the Apollo 11 mission. President Nixon hung a copy of Earthrise on the wall next to his desk in the Oval Office.

The picture of Earthrise was prominently visible during news coverage of President Nixon’s call with Apollo 11 astronauts on the lunar surface. Flat-Earthers find it strange Nixon already had the photo hung on the wall when the mission was still ongoing. These people are unaware that there are already several Apollo missions before Apollo 11, and Apollo 11 was only the first to land on the Moon.

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Zooming at the Moon

At the longest zoom, the Nikon P1000 has a field of view of 0.2°, which is equivalent to 1342 km at the Moon’s distance.

Flat-Earthers zoomed their Nikon P1000 at the Moon and claimed that they could not find flags and landers from the Apollo missions. In reality, the smallest objects on the lunar surface they can observe using their cameras are large city-sized objects.

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Communication Delays in Apollo Missions

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Radio waves travel at the speed of light; it takes 1¼ seconds to cover Earth-Moon distance. It is the reason in the Apollo missions after Houston says something, the response from the astronauts on the Moon will arrive only after 2½ seconds.

Some presentations of the Apollo missions are edited to cut out the gaps created by the delay, and flat-Earthers use them to dismiss the Apollo missions as fake. However, in the actual audio recordings and the transcripts, the delays are there.

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Blue Marble and the Visible Area of Earth’s Surface

The Blue Marble is an image of Earth taken by the crew of the Apollo 17 spacecraft on its way to the Moon. It was taken from a distance of 29000 km from Earth’s surface.

Flat-Earthers dismiss it by incorrectly asserting that the image covers a too-small area of Earth’s surface, due to their failure to account for the maps’ distortion.

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Wikileaks Video Hoax

Someone created a fake video showing the “fabrication” of the Apollo moon landings. It claims to be from Wikileaks, complete with its logo, a photo of Julian Assange, and various video effects for a semblance of authenticity. In reality, the video was taken from behind the scenes clips of the movie Capricorn One.

Wikileaks’ official website does not have the video, and the video is only available from dubious sources. It is not difficult to know the video is a blatant fake. However, flat-Earthers failed to recognize it is a fake, and the fake video spread in their communities as a hoax.

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Weightlessness, Free Fall, and Microgravity

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.

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Missions to the Moon, Post-Apollo

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.

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Angular Resolution

Angular resolution is the minimum separation between distinguishable features in an image. Objects smaller than the angular resolution are indiscernible in the picture. The theoretical maximum angular resolution is determined by the diameter of the aperture of the optical instrument.

Flat-Earthers like to demand images of the lunar landers taken with a telescope as proof that the Apollo Moon landings did occur. In reality, no optical telescope on Earth is large enough to resolve the landers.

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Apollo Astronauts and the Demand to Swear on the Bible

In the early 2000s, an unscrupulous Moon landing denialist lured Apollo astronauts into an audience with him under false pretenses. Then he insulted them as liars and pressed them to swear on the Bible that they went to the Moon.

Flat-Earthers use this incident as “evidence” that we never went to the Moon. In reality, the offender did not meet the astronauts with the best of intentions. This incident tells us more about the offender than it does about the astronauts.

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