2750: Flatten the Planets

2025-08-19T08:08:33Z

2A0A:EF40:C2:3201:5779:E28C:76F7:757B:

{{comic
| number = 2750
| date = March 15, 2023
| title = Flatten the Planets
| image = flatten_the_planets_2x.png
| imagesize = 740x647px
| noexpand = true
| titletext = We'll turn the asteroid belt into ball bearings to go between different rings orbiting at different speeds.
}}

==Explanation==
{| class="wikitable sortable floatright"
! rowspan="2" | Planet
! colspan="2" | Thickness
|-
!in
!mm
|-
| Mercury || 1/8" || 3.2 mm
|-
| Venus || 1" || 25 mm
|-
| Earth || 3/4" || 19 mm
|-
| Mars || 5/512" || 0.25 mm
|-
| Jupiter || 18" || 460 mm
|-
| Saturn || 3" || 76 mm
|-
| Uranus || 1/8" || 3.2 mm
|-
| Neptune || 1/16" || 1.6 mm
|}

This comic depicts a situation where the planets in the solar system are flattened to create a ring system around the Sun. This may be inspired by the {{w|Alderson disk}}, a hypothetical megastructure intended to gain truly massive amounts of living space by constructing a literal disk of matter around a star. This would require several solar systems' worth of matter to do, and materials with a tensile strength beyond what is likely physically possible for any known form of matter. The planets of our solar system would not be suitable for this endeavor; alas, Randall apparently cannot comprehend why {{w|NASA}} is rejecting this proposal to "improve" the planets. This comic may be a follow-up to [[2258: Solar System Changes]].

The title text explains what would happen to the asteroid belt if this was done. He is proposing that the asteroids should be turned into ball bearings to go in between the planetary discs. There is enough matter in the asteroid belt to do this, dependent upon the size and distribution of the ball bearings used, and furthermore it implies that the discs would actually have small gaps between them. Unless the discs were made of material with impossibly high tensile strength, the whole structure would soon be torn apart by the relative forces between the inner and outer fringes of each disc trying to both 'orbit' at the rate more suited to a radial distance somewhere between the two, and crushing the bearings placed between adjacent ones. Although less so than with a single structural disc rotating at any single given compromise rotation (or not at all).

After this comic was released, NASA <span class="plainlinks">[https://bsky.app/profile/xkcd.com/post/3klz7zr6s7i2x issued a three-page response]</span>, claiming that they do not have any records of rejecting it. In their response, they outline the various strengths and weaknesses of Randall's idea. In the end, NASA decided not to fund the project, for obvious reasons.
Strengths:
* Simplifies navigation of the Solar System
* Reduces need to study orbital dynamics
* Simplifies seasonal migration patterns as seasons no longer exist
* Would demonstrate the first real-world use of incredibly strong materials as regular materials could not withstand those strengths (NASA cites Laplace 1787 and undergraduate problem sets since then)
* Would increase the amount of ice skating, cross country skiing, and Keplerian ice-boat racing in the Outer Solar System
* Increases Solar System's visibility to galactic neighbors
* Easier visualization of the Solar System
* Removes ambiguity of comet and asteroid origins
* The night sky would be darker and there would only be night
* Would cause an actual collision with Apophis instead of a near miss
* Enables new methods of exploring the Solar System
Weaknesses:
* Would require rapid transfer of orbital assets
* Mars would be very thin and liable to being pierced by interplanetary dust particles
* Does not include Pluto
* Time scale was not sufficiently addressed
* The proposal did not address the varying density of the planets
* The proposal did not include details on the environmental impact. They said they believe this was an intentional ommision
* Results in the end of all Solar eclipses
* Slides and roller coasters would be much less entertaining due to reduced gravity
* Not enough information on the thickness of Kuiper Belt and Oort Cloud
* Did not sufficiently account for Mercury heating up and expanding due to solar energy from the Sun
* May conflict with the exploration of the secrets of the Universe

==Transcript==
:[This comic depicts a situation where the planets of the Solar System are flattened using a rolling pin to create a contiguous ring system around the Sun, with each planet taking up the part within their orbit to the next planet (or the Sun).]

:[The top part shows a normal image of the Solar System with the eight planets orbiting the Sun, and their orbits shown as circles. The Sun is yellow and the planets have approximately the color they typically are shown in. Earth has more features than the other three rocky planets. Jupiter has clear features including the red spot, while Saturn has its rings. Beneath this is a broad arrow pointing down.]
:↓
:[The arrow points to a rolling pin. A similar arrow points down to the next image.]
:↓
:[The second large image shows the Solar System with the planets flattened to fill out the gap between the Sun and each of the planets, so they each cover the area of the circle within their orbits, into the next planet (or the Sun). Each segment has kept a similar color as used for the planets in the first image. The Sun is not flattened and is now the center of a huge ring with eight different colors, some with patterns, mainly Earth, but also Jupiter and Saturn's discs show features.]

:[Beneath this to the right is a side view of the flattened Earth, with its thickness indicated with two arrows pointing in at the top and up at the bottom of two dotted lines continuing where the "Earth" stops. A label has been written between these two lines, and the thickness is compared to US quarter and penny coins.]
:Earth
:3/4"

:[Below this and going all the way across the panel is a side view with a segment of the Sun to the left followed by all the flattened planets, labeled with their name and their thicknesses. Arrows point to the relevant segment from the three rocky planets other than Earth. Above Jupiter and Saturn is a label between two arrows. Text alternates between being above and below the planets. Their thicknesses differ quite a lot, with Mars being the thinnest and Jupiter by far the thickest. Cueball stands on the flattened Earth.]
:← Not to scale →
:Mercury 1/8"
:Venus: 1"
:Earth 3/4"
:Mars 250 microns
:Jupiter 18"
:Saturn 3"
:Uranus 1/8"
:Neptune 1/16"

:[Caption below the panel:]
:I don't know why NASA keeps rejecting my proposals to improve the Solar System

{{comic discussion}}

[[Category:Comics with color]]
[[Category:Comics featuring Cueball]]
[[Category:Astronomy]]
[[Category:Space]]

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2750: Flatten the Planets