2783: Ruling Out

2025-12-20T23:03:55Z

2600:1700:94A0:6BE0:8066:23AC:7388:B268: /* Explanation */

{{comic
| number = 2783
| date = May 31, 2023
| title = Ruling Out
| image = ruling_out_2x.png
| imagesize = 295x396px
| noexpand = true
| titletext = We were able to replicate and confirm prior authors' detection of a moon orbiting the Earth with high confidence.
}}

==Explanation==
Most science studies are intended to discover new knowledge. In astronomy, the goal is often to find different types of objects in space, or learn how astronomical objects are formed and behave. But often from studying things that exist, we also learn about limits of the kinds of things that ''can'' exist; when this happens, we say that we've "ruled out" the excluded phenomena.

[[Cueball]] lists five impossible objects his team has ruled out:

* "Earthlike stars": A play on "Earth-like planets" which scientists are very interested in finding. The [https://solarsystem.nasa.gov/planets/earth/overview/ Earth] is ([[3063: Planet Definitions|probably]]) not a {{w|star}}, hence stars cannot be Earthlike (even other similarities (such as habitability and liquid water) are extremely hard to achieve, due to high gravity and sometimes very high temperature).
: Searches for both {{w|List of potentially habitable exoplanets|Earth-like planets}} and {{w|Solar analog|Sun-like stars}} go unabated, with various near matches found.

* "Exoplanets in our solar system": {{w|Exoplanet}}s are by definition not in our solar system.
: Planets in our solar system (even {{w|Planets beyond Neptune|undiscovered ones}}) are unaffected, as is the {{w|List of exoplanet search projects|search for exoplanets}} around other stars, with conclusive evidence of both.

* "Habitable-zone quasars": {{w|Quasar}}s in the {{w|habitable zone}}s of stars are only theoretically feasible for relatively small {{w|black hole}}s with active {{w|accretion disk}}s in a star's habitable zone, visible from the Earth and brighter than the Sun, because of the technical criteria for classifying them in terms of their {{w|apparent magnitude}} relative to that of their galaxy.[https://iopscience.iop.org/article/10.1088/0004-637X/728/1/26] None such have ever been observed. While typical galaxies usually have only one quasar in their center, merging galaxies often have two far apart. Perhaps in 4-5 billion years, when the {{w|Andromeda Galaxy}} merges with our {{w|Milky Way}}, its [https://www.sci.news/astronomy/article00779.html microquasar] might qualify, but that is extremely unlikely.
:While not certain, habitable zones around some quasars have not been ruled out.[https://iopscience.iop.org/article/10.3847/1538-4357/ab1b2f/meta][https://iopscience.iop.org/article/10.1088/1742-6596/2364/1/012057/meta]

* "Stars with subsurface oceans": Because the temperatures inside stars are higher than that which can support the existence of liquids as we understand them, stars cannot have subsurface oceans. After many billions of years, a {{w|white dwarf}} will cool to the point where it no longer emits significant heat or light, becoming a {{w|black dwarf}}, eventually cooling to the point where it might develop subsurface liquids.{{acn}} However, the universe is not old enough for any black dwarfs to exist yet,[https://iopscience.iop.org/article/10.1086/375341/pdf] and sufficiently cool black dwarfs might not even be considered stars, but rather {{w|rogue planet}}s.
: The possibility of subsurface oceans within various planets and moons is an {{w|Extraterrestrial liquid water|active subject of study}}, and was previously mentioned 10 comics ago in [[2773: Planetary Scientist]].

* "Tectonically active black holes": Black holes do not have {{w|tectonic plate}}s, so they cannot be tectonically active.
: There are theories that neutron stars can exhibit {{w|Quake (natural phenomenon)#Starquake|tectonic-like movements}} (as some of the more typical rocky bodies certainly do), but the physics of the 'inside' of a black hole are thought to involve {{w|Black hole#Singularity|strange physics}} incompatible with any form of geology, and cannot be observed anyway – it is believed that the only externally-observable properties of black holes are mass, electric charge, and angular momentum, poetically called the '{{w|no-hair theorem}}'.

The joke is that you don't actually have to study anything to come to these almost patently obvious conclusions. The objects are contradictory by their very names ("Exoplanets in the solar system") so the fact they ''can't'' exist would be obvious to most laypeople, much less a research in an astronomy-related field. The counter-proposals would need far more effort to even justify them as valid theories, by common understanding, and greater still to try to observe any supporting proof.

Some studies are also done to confirm the results of previous studies, to ensure that the conclusions were not mistaken or a fluke. The title text describes a study that was done to confirm the existence of a moon orbiting Earth, even though any sighted person can walk outside and see the Moon, the existence of the Moon has been known for at least as long as humanity has existed, and the fact that it orbits the Earth has been assumed or known for upwards of 3,000 years. The ancient Greeks and Babylonians, for example, thought that the Moon orbited the Earth, though they lacked a detailed physical understanding of the system (they also believed, erroneously, that {{w|Geocentric model|everything else in the universe orbited the Earth too}}). {{w|Anaxagoras}} (c. 500–428 BC) is credited with the correct explanation of lunar eclipses, and reportedly was the first to explain that the Moon shines due to reflected light from the Sun. However, it was not until the work of {{w|Nicolaus Copernicus}} in the 16th century that a detailed and accurate model of the Moon's orbit around the Earth was developed. Regardless, at this stage, a study to confirm the validity of Copernican orbits would contribute nothing to the scientific process, much less a study confirming the mere existence of the Moon.

==Transcript==

:[Cueball is talking to Megan.]
:Cueball: So far our astronomy group has published studies ruling out the existence of Earthlike stars, exoplanets in our solar system, habitable-zone quasars, stars with subsurface oceans, and tectonically active black holes.

:[Caption below the panel:]
:Science got way easier when we realized you were allowed to do studies just to rule stuff out.

{{comic discussion}}

[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Megan]]
[[Category:Astronomy]]
[[Category:Science]]
[[Category:Scientific research]]

3183: Pole Vault Pole

2025-12-20T09:14:10Z

2600:1700:94A0:6BE0:8066:23AC:7388:B268: /* Explanation */

{{comic
| number = 3183
| date = December 19, 2025
| title = Pole Vault Pole
| image = pole_vault_pole_2x.png
| imagesize = 550x464px
| noexpand = true
| titletext = My goal in life is to be personally responsible for at least one sports rule change.
}}

==Explanation==
{{incomplete|This page was created by a BOT OF UNLIMITED LENGTH. Don't remove this notice too soon.}}

The comic shows three hypothetical ways to cheat at {{w|pole vault}}, taking advantage of the fact that the rules don't limit the physical size of the pole. {{w|World Athletics}}' competition rules, rule 28.11, states, "The pole may be of any material or combination of materials and of any length or diameter, but the basic surface must be smooth."

The first way uses a pole that's short but with a very large diameter. It's then turned 90 degrees horizontally, so it can actually be used as a large wheel. The vaulter balances on top, then uses their feet to make it roll towards a crossbar at about the same height as the pole's diameter. When it reaches the bar, they simply jump a short amount to clear the bar.

The second method uses a pole whose length is more than twice the height of the crossbar. It's stretched over the bar and somehow attached to the ground at each end. Then the vaulter simply climbs up and over the bar.

The third method ties the ends of a very long and wide pole together, forming a large hoop that can be rolled towards the crossbar. The vaulter grabs onto the hoop, and when they reach the top they let go, and their momentum tosses them over the bar.

There are several flaws with these designs:

• Chiefly, the reason that the IAAF has not yet specified a standard measurement for poles is because there have not been any attempts to use a bizarre or potentially-advantageous design like these in sanctioned competitions. Were someone to try to do so, the authorities would {{tvtropes|ObviousRulePatch|take notice}} (though as we will see in the title text, Randall would count this as a win).

• The first design is hampered by its size; any material sturdy enough to take a human's weight would cause a wheel that big to be considerably massive, difficult for a human to start in motion from a dead stop, dangerous if the user falls off while rolling it down the track, and capable of continuing on after the vaulter makes their jump, dislodging the bar from the vaulting frame and thereby disqualifying the attempt.

• The second design needs a few minutes in order to be sturdily embedded in the take-off & landing pits, causing a lot of stress to gather along the bowed pole which could make it snap or suddenly dislodge itself. Climbing along the pole also does not meet the defined action of vaulting, which is the apogee of the vaulter's ascent when their momentum should carry them over the bar on their own.

• The third design combines the first design's risks of the vaulter falling off and dislodging the bar with the second's risk of snapping or coming unfurled.

The title text says that Randall wants to be responsible for a sports rule change. Based on the contents of the comic, the implication is that he would go about this by exploiting some loophole that the organizers would be forced to patch.

Pole vaulting and unfair methods of gaining height are also discussed in the first chapter of [[How To]].

==Transcript==
{{incomplete transcript|Don't remove this notice too soon.}}
:[At top left: A large wheel whose diameter is more than 4 times Cueball's height. Cueball is at the top, running backwards so that the wheel will roll towards a pole-vaulting crossbar at the same height.]
:[At top right: A long pole is bent into an arch going over a very high pole-vaulting crossbar. Cueball is climbing up the left part, and is about 3/4 of the way to the top.]
:[Along the bottom: A long pole has been bent into a circular hoop, with the ends tied together. It's rolling left-to-right towards a very high pole-vaulting crossbar, and three positions are shown. On the left Cueball is running to catch up with it. In the middle he has jumped and caught the left part of the pole. On the right, he has let go and is thrown into the air towards the crossbar.]
:[Caption below the panel:]
:Fun fact: There are no limits on the length or diameter of the pole in pole vault.

{{comic discussion}}<noinclude>

[[Category:Comics featuring Cueball]]
[[Category:Sport]]

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2783: Ruling Out

3183: Pole Vault Pole