# Historical views about the revolution of the Moon **URL:** \ **Category:** Factual Questions\ **Created:** [May 13, 2022, 7:26pm UTC](https://boards.straightdope.com/t/historical-views-about-the-revolution-of-the-moon/964384 "2022-05-13T19:26:29Z")\ **Posts on this page:** 14\ **Page:** 1
**Author:** ![Schnitte](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/schnitte/32/9033_2.png) [@Schnitte](https://boards.straightdope.com/u/Schnitte)\ **Post date:** [May 13, 2022, 7:26pm UTC](https://boards.straightdope.com/t/historical-views-about-the-revolution-of-the-moon/964384/1 "2022-05-13T19:26:29Z")
Copernicus and Galilei did away with Ptolemy’s belief that the Earth was at the centre of the Universe, and that all other celestial bodies (plus a concentric set of “spheres”) revolve around it. But in one aspect Ptolemy actually was right, namely, the revolution of the Moon around the Earth. Was there ever any doubt about this in the history of astronomy? I’m wondering if there ever was a time when overzealous heliocentrics disputed this and postulated something else, such as a direct revolution of the Moon around the Sun. ---
**Author:** ![Stranger\_On\_A\_Train](https://avatars.discourse-cdn.com/v4/letter/s/13edae/32.png) [@Stranger\_On\_A\_Train](https://boards.straightdope.com/u/Stranger_On_A_Train)\ **Post date:** [May 13, 2022, 8:16pm UTC](https://boards.straightdope.com/t/historical-views-about-the-revolution-of-the-moon/964384/2 "2022-05-13T20:16:27Z")
That seems unlikely. Even with the naked eye it is easy to see that the same side of the Moon faces the Earth, and the phases of the Moon are readily explicable only if you assume it is orbiting (not rotating) about the Earth. Stranger ---
**Author:** ![dtilque](https://avatars.discourse-cdn.com/v4/letter/d/d6d6ee/32.png) [@dtilque](https://boards.straightdope.com/u/dtilque)\ **Post date:** [May 13, 2022, 11:37pm UTC](https://boards.straightdope.com/t/historical-views-about-the-revolution-of-the-moon/964384/3 "2022-05-13T23:37:53Z")
Even [Tycho’s alternate theory](https://en.wikipedia.org/wiki/Tychonic_system), which was a hybrid of Ptolemy and Copernicus, had the Moon orbiting the Earth. ---
**Author:** ![OldGuy](https://avatars.discourse-cdn.com/v4/letter/o/3bc359/32.png) [@OldGuy](https://boards.straightdope.com/u/OldGuy)\ **Post date:** [May 13, 2022, 11:53pm UTC](https://boards.straightdope.com/t/historical-views-about-the-revolution-of-the-moon/964384/4 "2022-05-13T23:53:28Z")
The gravitational force of the Sun on the Moon is twice that of the Earth, and the Moon’s orbit is every concave towards the Sun. So in a sense it does orbit the Sun. ---
**Author:** ![TriPolar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tripolar/32/3008_2.png) [@TriPolar](https://boards.straightdope.com/u/TriPolar)\ **Post date:** [May 14, 2022, 12:23am UTC](https://boards.straightdope.com/t/historical-views-about-the-revolution-of-the-moon/964384/5 "2022-05-14T00:23:46Z")
It’s the same sense that the Earth orbits the sun, [by traveling around it.](https://en.wikipedia.org/wiki/File:Earth_orbit.svg) ---
**Author:** ![Riemann](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/riemann/32/3133_2.png) [@Riemann](https://boards.straightdope.com/u/Riemann)\ **Post date:** [May 14, 2022, 1:02am UTC](https://boards.straightdope.com/t/historical-views-about-the-revolution-of-the-moon/964384/6 "2022-05-14T01:02:37Z")
> [@OldGuy](#): > > the Moon’s orbit is every concave towards the Sun I don’t think this is true. The Moon is not pulled toward the Sun away from the Earth. Both Earth and Moon are traveling at the “correct” speed to orbit the Sun at this distance if the other body were not there; with both bodies present the barycenter of the Earth-Moon system orbits the Sun. To the extent the Moon’s orbit is non-circular, the ellipse is not oriented consistently relative to the Sun. ---
**Author:** ![DPRK](https://avatars.discourse-cdn.com/v4/letter/d/4491bb/32.png) [@DPRK](https://boards.straightdope.com/u/DPRK)\ **Post date:** [May 14, 2022, 1:39am UTC](https://boards.straightdope.com/t/historical-views-about-the-revolution-of-the-moon/964384/7 "2022-05-14T01:39:23Z")
What does your answer mean? It is true that the Moon is not pulled away from the Earth toward the Sun, and it is equally true that the Moon is not pulled away from the Sun towards the Earth, and follows a convex orbit around the Sun. ---
**Author:** ![Riemann](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/riemann/32/3133_2.png) [@Riemann](https://boards.straightdope.com/u/Riemann)\ **Post date:** [May 14, 2022, 1:47am UTC](https://boards.straightdope.com/t/historical-views-about-the-revolution-of-the-moon/964384/8 "2022-05-14T01:47:32Z")
never mind ---
**Author:** ![OldGuy](https://avatars.discourse-cdn.com/v4/letter/o/3bc359/32.png) [@OldGuy](https://boards.straightdope.com/u/OldGuy)\ **Post date:** [May 14, 2022, 1:47am UTC](https://boards.straightdope.com/t/historical-views-about-the-revolution-of-the-moon/964384/9 "2022-05-14T01:47:46Z")
I said concave towards the sun, this site describes it as convex meaning the shape enclosed is convex. They mean the same thing. > ---
**Author:** ![Riemann](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/riemann/32/3133_2.png) [@Riemann](https://boards.straightdope.com/u/Riemann)\ **Post date:** [May 14, 2022, 1:51am UTC](https://boards.straightdope.com/t/historical-views-about-the-revolution-of-the-moon/964384/10 "2022-05-14T01:51:12Z")
> [@OldGuy](#): > > I said concave towards the sun The way you phrased your original post it appeared that you were claiming that the Moon’s orbit around the _Earth_ was distorted by the Sun. ---
**Author:** ![DPRK](https://avatars.discourse-cdn.com/v4/letter/d/4491bb/32.png) [@DPRK](https://boards.straightdope.com/u/DPRK)\ **Post date:** [May 14, 2022, 2:02am UTC](https://boards.straightdope.com/t/historical-views-about-the-revolution-of-the-moon/964384/11 "2022-05-14T02:02:38Z")
As for the exact shape of the Moon’s orbit around the Earth, well, that is a centuries-long rabbit hole > **[Lunar theory](https://en.wikipedia.org/wiki/Lunar_theory)** > > Lunar theory attempts to account for the motions of the Moon. There are many small variations (or perturbations) in the Moon's motion, and many attempts have been made to account for them. After centuries of being problematic, lunar motion can now be modeled to a very high degree of accuracy (see section Modern developments). > Lunar theory includes: > Lunar theory has a history of over 2000 years of investigation. Its more modern developments have been used over the last three centuries for fundam... The Sun effects all sorts of crazy perturbations/distortions, a few of which were known in ancient times (e.g., evection), but to approach modern standards of accuracy you need thousands of terms. ---
**Author:** ![naita](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/naita/32/5862_2.png) [@naita](https://boards.straightdope.com/u/naita)\ **Post date:** [May 14, 2022, 12:52pm UTC](https://boards.straightdope.com/t/historical-views-about-the-revolution-of-the-moon/964384/12 "2022-05-14T12:52:45Z")
The heliocentric model won out because it was a simpler explanation than the epicycles required to explain retrograde motion of the planets. The Moon with its very regular orbit never required such a simplification, so if anyone ever suggested it it would have been because they were absolutely terrible astronomers. When looking at the available information to astronomers it’s not that surprising the geocentric model was the most popular for so long. The Moon obviously orbits the Earth in a nice patter. The Sun does the same. All the fixed stars do too. That there’s also a few “wandering stars” doesn’t seem like a reason to search for a “better” explanation until you get a telescope and discover how majorly different they are from the fixed stars. ---
**Author:** ![k9bfriender](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/k9bfriender/32/3283_2.png) [@k9bfriender](https://boards.straightdope.com/u/k9bfriender)\ **Post date:** [May 14, 2022, 2:15pm UTC](https://boards.straightdope.com/t/historical-views-about-the-revolution-of-the-moon/964384/13 "2022-05-14T14:15:18Z")
> [@naita](#): > > That there’s also a few “wandering stars” doesn’t seem like a reason to search for a “better” explanation until you get a telescope and discover how majorly different they are from the fixed stars. And you start to see that they have moons of their own. ---
**Author:** ![74westy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/74westy/32/3950_2.png) [@74westy](https://boards.straightdope.com/u/74westy)\ **Post date:** [May 14, 2022, 4:21pm UTC](https://boards.straightdope.com/t/historical-views-about-the-revolution-of-the-moon/964384/14 "2022-05-14T16:21:18Z")
> [@naita](#): > > When looking at the available information to astronomers it’s not that surprising the geocentric model was the most popular for so long. Looking at dtilque’s link: > [@dtilque](#): > > [Tycho’s alternate theory](https://en.wikipedia.org/wiki/Tychonic_system) I see: > [@Wikipedia](#): > > In regard to physics, Tycho held that the Earth was just too sluggish and heavy to be continuously in motion. According to the accepted Aristotelian physics of the time, the heavens (whose motions and cycles were continuous and unending) were made of [“Aether” or “Quintessence”](https://en.wikipedia.org/wiki/Aether_(classical_element)); this substance, not found on Earth, was light, strong, and unchanging, and its natural state was circular motion. By contrast, the Earth (where objects seem to have motion only when moved) and things on it were composed of substances that were heavy and whose natural state was rest. Consequently, the Earth was considered to be a “lazy” body that was not readily moved.[[7]](https://en.wikipedia.org/wiki/Tychonic_system#cite_note-7) If this was the accepted science of the time, it’s hardly surprising that good scientists created bad theories. Any good theories would have shattered the foundations.