2709: Solar System Model

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Solar System Model
The Earth is, on average, located in the habitable zone, but at any given time it has a certain probability of being outside it, which is why life exists on Earth but is mortal.
Title text: The Earth is, on average, located in the habitable zone, but at any given time it has a certain probability of being outside it, which is why life exists on Earth but is mortal.


This comic parodies the analogy of early-20th century models of atomic structure to the structure of the solar system. Electrons were thought to be orbiting the nucleus "like planets around a sun" until it was discovered that their locations are probabilistic. The comic flips this on its head: instead of the atomic structure model lacking a known causal relationship, it is now the planetary system that is quantum mechanical in nature, split into probabilistic orbitals.

Miss Lenhart is shown here to be teaching an astronomy class, and claims that it was thought that the planets moved around the sun like electrons around the nucleus before this model was superseded by the probabilistic quantum mechanical view of orbital locations for planetary movement.

This is another one of the comics where Lenhart tries to fool her class, as in for instance 1519: Venus. Most likely it is not to be taken to be true that her world is like this, or that she believes in it. She just likes to mess with her students.

If what she said was to be taken literally it would suggests that in this reality not only do electrons have distinct bodies that orbit a nucleus, but also that atomic structure was known before the correct planetary one.

In reality, the description of probabilistic orbitals is applied to the electrons in an atom; quantum uncertainty effects are not large enough to notice at the planetary scale[citation needed]. However, such a concept has been prominently featured in the video game Outer Wilds, with its Quantum Moon. Immanuel Velikovsky proposed that our solar system's planets could jump between orbits suddenly, quantum-mechanically, in the same way that electrons do around atomic nuclei. This proposal was not well received in academia. Real astronomers do talk about probability distributions of orbiting bodies, especially in the context of collision calculations, but it's not because the position of a satellite or asteroid is in a quantum superposition of states; rather, it is our less than infinite accuracy of measurement and knowledge of those orbits, plus their evolution under the influence of less-predictable effects like space weather or other still unidentified additional factors, that makes long-term estimates progressively more uncertain.

The title text is Miss Lenhart trying to use the first joke to set up another that builds on the first. She says that the consequence of planets having probabilistic locations would mean that they would spend some time in the lower-probability locations closer to or further from the Sun. The Earth's real orbit is in a so called habitable zone where the temperature allows liquid water and thus allows life as we know it to exist. A probabilistic Earth would spend most of its time in the habitable zone, which is why life exists, but then, in short periods when it is outside the zone, some life would die. The title text claims this is why life on Earth is mortal, thus indirectly implying that life only dies in the periods where Earth leaves the habitable zone, and that life staying in the habitable zone would be immortal.

There was already an orbital model parody made in 2100: Models of the Atom, which featured the planetary one, but at that time it was solely for the humorous insertion of 'facts' into the subject of atomic theory.


[Miss Lenhart is teaching a class. In front of her sits a student with curly hair at his desk pen ready on the paper to write notes. The front of the next table behind him can be seen. Behind Lenhart is a white board with two drawings and a large underlined header at the top. The drawing beneath the header shows a solar system with a radiating sun and two planets orbiting with the orbits shown and the planets marked with small circles, one on either side of the sun, both above the sun. Beneath this is another sun in the middle of either a group of four eight-like shapes, or a diagram similar to the usual depiction of the 4fxyz or 4fzx2 - zy2 orbitals. Lenhart points at the board with a pointing stick while looking out over the class.]
Miss Lenhart: Early 20th century models of the solar system imagined that planets circled the Sun like electrons in an atom.
Miss Lenhart: We now know planets have no precise location, but instead occupy probabilistic orbitals...
Header: Astronomy

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Like the Quantum Moon from Outer Wilds. DanielLC (talk) 06:30, 10 December 2022 (UTC)

The lead sentence needs correcting: ELECTRONS orbit the nucleus, not ATOMS orbit the nucleus (talk) 08:54, 10 December 2022 (UTC) 08:56, 10 December 2022 (UTC)

Fixed. —While False (museum | talk | contributions | logs | rights | printable version | page information | what links there | related changes | Google search | current time: 00:15) 09:10, 10 December 2022 (UTC)

Also, the electrons ORBIT, not REVOLVE. (talk) 09:01, 10 December 2022 (UTC) 09:01, 10 December 2022 (UTC)

You can fix that yourself? click the edit button and replace it. That's... the whole point of wikis i'm pretty sure. 14:36, 10 December 2022 (UTC)Bumpf
Yes, That is what I was trying to do but was locked out. Leaving a message was the next best thing. 08:36, 11 December 2022 (UTC)

When I first read the comic, I was confused about Randall (Ms. Lenhart) describing quantum orbitals correctly. See, I knew the real history of science, so my brain autocorrected it to read that we used to think electrons had elliptical orbits. I had to look three times before I even saw the inversion. Nitpicking (talk) 16:28, 10 December 2022 (UTC)

Someone should add something about Lyapunov time, and how orbits are unpredictable on longer timescales. 16:59, 10 December 2022 (UTC)

(talk) 3:42, 10 December 11 (UTC) Someone PLEASE explain this to me like I'm five? The explanation confused me :(

In the early 20th century atoms was in some respects believed to behave similar to solar systems, in that electrons orbited around the core of the atom like planets orbit around their sun. Nowadays, it has been discovered that electrons do not orbit around the core of the atom in such a manner; rather, the position of electrons are described with a more complicated model involving so called orbitals and probabilities. However, planets are still considered to orbit around their sun. The joke in this comic is that it claims the opposite: that atoms are still imagined with electrons in simple orbits, while planets have turned out to move according to the more complicated model with orbitals and probabilities. If this is amusing, it is probably because it is an absurd thought that something as big as planets would move in such an unintuitive way, which can not be described with classical mechanics. It may also be amusing that the history writing in the comic is very similar but opposite to the accepted one.
While False (museum | talk | contributions | logs | rights | printable version | page information | what links there | related changes | Google search | current time: 00:15) 05:29, 11 December 2022 (UTC)

It's not space weather which makes position of planets hard to predict. It's the fact that while we have exact equations for two bodies, Three-body problem has no closed-form solution and leads to chaotic behaviour ... and there is little more than three bodies in our solar system. Also note that it gets even more complicated when you add theory of relativity into the mix. -- Hkmaly (talk) 07:42, 11 December 2022 (UTC)

Space weather and uncountable minor bodies that have not yet been recorded and the inability to provide current motion/mass data to quite impossible levels (even for those bodies we haven't missed) lead to potentially chaotic divergences in the future.
What Mars does in a million years might depend upon solar activity, precisely where it is in its orbit compared to the other major planets, whether any comet has purturbed its moons or indeed what humans have done to/around it (nudged some comets towards it, assembled a web of space elevators from its adjusted satellites and imported asteroid-belt masses, caused it to lose mass for various intentional practical or accidental reasons, who knows..?).
Even ignoring anthropogenic changes, a slightly slower/faster orbit would effect the other planets (at least the inner rocky ones, but probably Jupiter gets resonated differently, eventually, thenceforth most of the system readjusts), which would in turn effect Mars again.
It is a chaotic system, and basic unknowns such as whether one or more CME will directly engulf any given inner planet (and when) are a detail that can drastically change the already fuzzy propobabilities of exactly when resonances conspire to make great changes to the current astronomical models. Refining the probabilities (based upon current understanding of various odds involved) is a continuous problem, and can never even rule out something unpredictable making even 'short'-term predictions all wrong. You can emperically run an idealised N-body problem through (with multiple runs to encompass the latitude of uncertainty in overtly known values, if you wish, as with weather services) but when something makes it an (N+m)-body problem, all bets are off, to the degree you did not anticipate the extra complications. 19:08, 13 December 2022 (UTC)

Of course, we now know that the planets are actually styrofoam balls held up by bits of string. 22:02, 11 December 2022 (UTC)

ChatGPT sez: "The comic is about a teacher teaching a class about astronomy and how the models of the solar system have changed over time. In the past, it was believed that planets circled the sun in precise paths, like electrons orbiting the nucleus of an atom. However, we now know that planets do not have a fixed location and instead occupy "probabilistic orbitals," which means that their position is not certain but can be predicted with a certain probability. The title text suggests that this probabilistic model of planetary orbits also applies to the Earth's position in the habitable zone, where conditions are suitable for life. This is why life exists on Earth but is also mortal."

Nope. 23:55, 11 December 2022 (UTC)

I just want to say that "This proposal was not well received in academia" was very funny! Well done, whoever wrote that.

Thank you! I was originally going to explain how nonsensical the idea was. And how every time Velikovsky made an assertion in field X, all of the experts in that field thought it was silly but were willing to accept his claims about other fields. I was concerned that to do so might attract the attention of his loyal followers, who still are out there, which would result in edit wars and vandalism. Then I realized that a very dry NPOV would do. BunsenH (talk) 17:00, 13 December 2022 (UTC)

IF I understand quantum mechanics correctly the chance of switching orbits is the chance of the electron suddenly switching locations to a far distance (exceedingly low [citation needed]) multiplied by the inverse ratio of all the electrons in the planet (exceedingly high [citation needed]) which makes a super exceedingly low number [citation: all the math classes where I tried multiplying low ratio numbers and they got smaller. the lower the ratio the smaller the number -- {math is fun <yes it is shuttup>}] So I think that all scientists believe that the planets can switch their orbits, but the chances of this are a) VERY EXCEEDINGLY SUPER LOW and b) about 100% chance going to end up with an unstable orbit [citation the quantum possibility of the entire planet moving to another orbit doesn't change the velocity or acceleration with regard to the new orbital position's relation to the sun's gravitational pull thus with the old velocity and new position's gravitational pull the orbit is no longer a stable one]. CONCLUSION: the statement "This proposal was not well received in academia" may be inadequate. The chances are probably well within 1/TREE(3) chances of happening and I would be shocked if they were not withing 1/TREE(TREE(3)).

QM applies to all objects, not just electrons. For example, all of the QM behaviour that we're used to applying to electrons is also seen for neutrons: diffraction, double-slit experiments, etc., but scaled appropriately for the mass difference. There is QM uncertainty associated with objects of planetary mass, it's just really really tiny. Planetary objects do change their orbits by absorption and emission of quanta, but the changes in those orbits are unobservably small. Velikovsky was proposing orbit changes on the scale of a solar system. Supposedly, after Venus was barfed out of Jupiter, QM effects caused it to go ping-ponging around the solar system, and its repeated passing by Earth created several of the Biblical miracles. One of the (many) problems with the concept is that it would require the absorption and emission of quanta that would be proportionately enormous, to account for the changes in energy and momentum. BunsenH (talk) 17:00, 13 December 2022 (UTC)

“ quantum uncertainty effects are not large enough to notice at the planetary scale…”

What if you had a cat the size of six solar masses and put it in a box with…