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To: daniel1212

Dig deeper.

Try stepping on a moving treadmill and watch what happens next.


108 posted on 09/03/2025 5:49:43 AM PDT by cgbg (It was not us. It was them--all along.)
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To: cgbg
Dig deeper. Try stepping on a moving treadmill and watch what happens next.

Dare I ask you to elaborate your argument, vs. cryptic one sentence statements. I suppose your analogy refers to landing on the moon, which takes approximately 27 days for the moon to rotate once on its axis. Earth spins around its axis at up to 1,038 miles per hour. To which applies:

Moon landing deniers often claim that landing on the Moon would be like trying to step onto a fast-moving treadmill, arguing that the Moon’s surface rotation (about 10.3 mph at the equator) and the Earth’s rotation (about 1,037 mph at the equator) must make landing impossible or impractical. Here’s why this analogy is incorrect:


The Moon’s Rotation: The Real Numbers

  • The Moon rotates very slowly on its axis—about 10.3 miles per hour (16.7 km/h) at its equator—taking 27.3 days to complete one rotation.astronomy

  • The Earth’s equator rotates much faster—about 1,037 mph (1,670 km/h).space+1


Why "Stepping on a Treadmill" Is the Wrong Analogy

  • Spacecraft and their targets (like the Moon) are traveling together through space, each with their own rotational and orbital velocities.

  • When Apollo missions traveled to the Moon, the spacecraft were inserted into lunar orbit and their speed was matched to the Moon’s. This means the lander wasn’t trying to “step onto” a moving target like someone jumping onto a spinning treadmill; rather, it was already moving with the Moon before descent.

  • When a lander approaches the lunar surface, it decelerates relative to the Moon’s ground, and a gentle vertical touchdown is made as their speeds match.

  • The same principle applies for returning to the moving Earth—spacecraft use orbital mechanics to synchronize with Earth’s rotation and atmosphere for a safe reentry.reddit+1


Tidal Locking and Predictability

  • The Moon is tidally locked to Earth, meaning the same side always faces us. The rotation is so slow and predictable that landing sites remain “in view” for more than a week at a stretch, unlike the rapid spinning of the Earth’s surface.


Summary Table

BodyEquatorial Rotation SpeedLanding/Takeoff Challenges
Earth~1,037 mphManaged through matching rotation/speed
Moon~10.3 mphVery slow, easily matched for gentle landing
 

In reality, Moon landings involved careful calculation of both the Moon’s movement and the spacecraft’s own motion—matching speeds before touchdown, not “jumping onto a treadmill.” This is standard practice in all rendezvous in spaceflight, whether docking, landing, or reentry.astronomy+1

  1. https://www.astronomy.com/science/what-is-the-speed-of-the-moons-terminator/
  2. https://en.wikipedia.org/wiki/Orbit_of_the_Moon
  3. https://en.wikipedia.org/wiki/Moon
  4. https://www.space.com/33527-how-fast-is-earth-moving.html
  5. https://www.youtube.com/watch?v=IVvAp5aQ5cs
  6. https://study.com/academy/lesson/earths-rotation-facts-speed.html
  7. https://www.reddit.com/r/askscience/comments/17w8g6f/how_do_we_accurately_land_back_on_earth_if_the/
    Source: https://www.perplexity.ai/search/what-is-the-raio-of-105-office-98lmZhzARESy7SsdfbTnpg#19

109 posted on 09/04/2025 3:37:30 AM PDT by daniel1212 (Turn 2 the Lord Jesus who saves damned+destitute sinners on His acct, believe, b baptized+follow HIM)
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