Digital Scans of Images From the Apollo Missions

Before 2009, Apollo missions images that we saw were scanned from the secondary copies that NASA distributed to research facilities after each mission. Only in 2009 NASA made high-resolution scans from the original films & made them available to the public.

Today, we can still find the older scan results. Flat-Earthers like to find defects in these low-quality scans & use the fact as “evidence” they are just paintings. In reality, they are scanned from the printed photos, which can preserve the texture of the photo paper itself.

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Apollo 8 vs Apollo 11 Earthrise Photos

A hoax in flat-Earth circles claims that Earth in the Earthrise photo taken by Apollo 8 is identical to a similar photo taken by Apollo 11. In reality, they are clearly not identical at all.

It might have been caused by an error by an online source or someone trolling flat-Earthers. However, it demonstrates flat-Earthers’ lack of critical thinking, as it can be easily shown the claim is false by finding the originals from NASA’s image archive.

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NASA’s Non-Fisheye Images

NASA maintains a database of astronaut photography in that we can search by many parameters, including focal length. By searching for focal length above 28mm, we can ensure the resulting images are not fisheye.

Flat-Earthers claim all NASA images are fisheye. In reality, most images in are not fisheye. NASA also preserves the images’ EXIF data containing the camera & lens info. Sometimes even the raw images are available.

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Overlay in Geographic Information System (GIS)

In geographic information system (GIS), overlay is an operation that superimposes layers of geographical data —like maps, satellite photos, roads, borders, etc— on top of each other.

Some satellite photos of Earth at night show country borders and shorelines. Flat-Earthers use the fact to dismiss the images as fake. They claim there are no lights illuminating the border on the ground, therefore the borders should not be visible. In reality, the borders are just an overlay added on the top of the original image. They are not part of the original satellite image.

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Fact-Fabrication Blending in Conspiracy Theories

Perpetrators of conspiracy theories, including flat Earth, like to mix real-world facts & their fabrications. As a result, the victims cannot differentiate the fact parts and the fabrication parts of the conspiracy, then wrongly use references to the fact parts as “evidence” of the fabrication parts.

For example, they often wrongly use the fact that Illuminati was real as “evidence” they control our lives. In reality, Illuminati was a real-world, historical secret society. But it does not prove that Illuminati is controlling everything in our lives.

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Multiple Exposure Photos of Balloons and SpaceX StarLink Satellites

To monitor the ozone hole, NOAA launches a balloon every week on several locations on Earth. Scientists who launch the balloons like to create multiple exposure photos of the event. A single balloon appears multiple times in the resulting photos.

Flat-Earthers saw the “many balloons in a row” photos, & they incorrectly use them as the “explanation” of the appearance of the SpaceX Starlink satellites. In reality, the photos are just multiple exposure photos. There is only a single balloon, but taken multiple times and then merged into a single photo.

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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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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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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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Lunar Transit Images from DSCOVR-EPIC

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DSCOVR is a spacecraft positioned in the Lagrangian point L1 between the Sun and Earth. It carries the EPIC camera that continuously takes images of Earth in 10 wavelengths from 317nm to 780 nm in rotation.

The Moon can appear in EPIC images, and flat-Earthers incorrectly use the color fringing around the Moon to dismiss the images as fake. In reality, the full-color images are composite of three single-color images taken in consecutive exposures in a one-minute span. As a result, the Moon had shifted in the time span and not perfectly aligned in the different exposures, causing the color-fringing after the images are composited together.

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The Saros Cycle and Saros Series

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The Saros is a period of 18 years, 11 days, and 8 hours between related eclipses. The eclipses with the same Saros cycle are classified into a Saros series which is numbered for identification.

Flat-Earthers claim the usage of the Babylonian term Saros “proves” that eclipses are predicted using ancient Babylonian technology. In reality, the Saros is now used to classify related eclipses. For example, the solar eclipse on August 21, 2017 is the 22nd member out of 77 in the Solar Saros 145.

The term Saros was first used in association with eclipse by Edmond Halley in 1691. The Babylonians never used the term Saros to describe eclipses. And the numbering system of the Saros series was created by G. van den Bergh in 1955.

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Predicting Eclipses Does Not Require the Saros Cycle or NASA’s Involvement

Using the current computing power, predicting eclipses is usually done iteratively. We determine the position of the Sun and the Moon at a time and calculate their elongation to determine if an eclipse happens. This same procedure is then repeated many times, each for a different time.

Flat-Earthers insist that nobody can predict eclipses from the position of the Sun and the Moon. They incorrectly believe NASA used the ancient Saros cycle to predict eclipses by calculating the interval between eclipses. A tiny Python script can easily debunk it.

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ISS Construction Video

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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”

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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2001 Mars Odyssey Launch Video

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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.

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Flight Dynamics: the Assumption of Flat & Non-Rotating Earth for Simplification

In making mathematical models, physicists often remove real-world details that have little influence over the final results for simplifications. In flight-dynamics, it is often perfectly adequate to assume Earth is flat & non-rotating, even if the final aircraft will be flying over spherical & rotating Earth.

Flat-Earthers claimed to have exposed ‘a secret document’ from NASA, saying that Earth is flat & non-rotating. In reality, the document is simply a derivation of a flight dynamics problem, assuming flat and non-rotating Earth, which is a common assumption made to simplify flight models. It does not imply the Earth is flat and non-rotating.

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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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“Mouse” on a SpaceX Falcon9 Rocket Launch

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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.

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Curved Appearance of a Rocket Trajectory

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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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Rocket Staging

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.

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