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| | ==Explanation== | | ==Explanation== |
| | + | {{incomplete|Created by a CAT-LOVING LASER POINTER - Please change this comment when editing this page. Do NOT delete this tag too soon.}} |
| | + | Space is really, really big,{{citation needed}} and the things that are in space can also end up being very big themselves. As a result of this, most quantities in astronomy can vary by huge scales. For example, Earth weighs 10^23 times more than the average human, and the Sun weighs 10^5 times more than that, which itself is 10^12 times less massive than the Milky Way. The same applies to speeds, distances, and time, which can often be measured in terms of light speed, light-years, and millions (or even billions) of years. Because of this, it's a truly unusual occurrence for anything in space to end up in the fairly narrow range of scales of mass, size, speed, or time that humans can easily grasp. |
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| − | Space [https://neal.fun/size-of-space/ is big], to the point that it regularly defies our earthly notions of scale. As a result, most quantities in astronomy have huge scales beyond anything that humans regularly experience or measure. (In fact, the word "astronomical" is sometimes used colloquially to describe any extremely large quantity).
| + | Ponytail, a scientist apparently researching something related to Earth's orbit, remarks that she finds it “suspicious” when reasonably human-scaled numbers come up. She then extends this paranoia to things that should be measured in regular numbers, such as the weight of cats. The vet (Megan) is seemingly used to this problem (perhaps she gets a lot of physicists) so restates the 12 lb weight of Ponytail’s cat in solar masses, which sounds more correct to the astronomer. |
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| − | For example, Earth has a mass 10<sup>23</sup> times more than the average human, and the Sun is 10<sup>5</sup> times more than that, which itself is 10<sup>12</sup> times less massive than the Milky Way. The same applies to speeds, distances, and time, which can often be measured in terms of light speed, light-years, and millions or billions of years. Because of this, it's a truly unusual occurrence for anything in space to end up in the fairly narrow range of scales of mass, size, speed, or time that humans can easily grasp.
| + | Although the Earth's orbital velocity around the Sun is far above any "normal" scales (around 30 kilometers per second or 108,000 kilometers per hour), Earth has a pretty circular orbit around the Sun so most of this speed ends up being tangential (sideways) rather than radial (towards or away from) the Sun, which is the value relevant for Ponytail's calculations. On January 1, Earth's radial velocity is close to its smallest value because we reach our closest point to the Sun in the first few days of January each year (in 2023, happens on January 4) so by January 1, it's nearly come to a standstill before it starts travelling away from the San again. On the other hand, by April 3, 2023, Earth will be receding from the Sun by almost 500 meters per second or 1800 kilometers per hour, a slightly less normal speed for the average person to encounter in everyday life.{{citation needed}} |
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| − | [[Ponytail]], apparently a scientist researching something related to Earth's orbit, finds that on a particular date, Earth will be approaching the sun at a velocity of 65 miles per hour. To American ears, this is a very normal sounding value (i.e. the speed of a fast-moving vehicle, often used as a speed limit on highways in the US). As Ponytail is accustomed to astronomical values, she is thrown off by this, and remarks that she finds it "suspicious" when reasonably human-scaled numbers come up in astronomy.
| + | 65 miles per hour is approximately equal to 105 kilometres per hour, although the even more typical scientific value (in {{w|International System of Units|SI}} derived units) would be 29 metres per second. 3 × 10^−30 solar masses is approximately equal to 6 kilograms or 13 pounds (consistent with the 12 pounds, or slightly under 5.5 kilogrammes, of the original figure) and is normal, if perhaps slightly overweight, for a cat. |
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| − | However, Ponytail seems to take this philosophy to an absurd degree by insisting that ''all'' scales should be as incomprehensible as astronomical ones, even those used for human-scale measurements, such as the weight of cats. In the third panel, the vet, [[Megan]], is seemingly used to this problem (perhaps she gets a lot of astronomers, or Ponytail has a hypochondriac cat), so she restates the 12-lb weight of Ponytail's cat in solar masses. Since using this unit yields an ''incredibly'' small number, 3×10<sup>-30</sup> (a three preceded by a decimal point and 29 zeroes), it satisfies Ponytail's need for incomprehensibly-scaled values. This weight is in fact about 13 lb 2 oz (about 5.5 kilograms), slightly heavier than the initial figure given for the cat, but within [[2585: Rounding|rounding error]] for the single digit of precision that Megan uses.
| + | The title text suggests that laser pointers "love chasing" a new cat with a weight of 12 solar masses (an inversion of the typical cat behavior of [[729: Laser Pointer|chasing laser pointer dots]]). This is presumably due to the effects of gravity, which would cause an ordinary object such as a laser pointer to be irresistibly pulled towards the hypothetical cat... along with everything else, up to and including the sun, because said cat would be the most massive object in the solar system by an order of magnitude. In fact, 12 solar masses, when compressed down to a radius of around 36 kilometres, would be a black hole, so making that mass the size of a cat would very definitely qualify as even the laser light is drawn into it. |
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| − | The Earth's orbital velocity around the Sun is far above normal human scales (around 30 kilometers per second or 108,000 kilometers per hour). However, Earth has a fairly circular orbit around the Sun, so most of this speed ends up being tangential (sideways) rather than radial (towards or away from) the Sun, which is the value relevant for Ponytail's calculations. On January 1 (the date being discussed in the comic), Earth's radial velocity is close to its smallest value because we reach our closest point to the Sun in the first few days of January each year (in 2023, {{w|Perihelion|perihelion}} happens on January 4). Thus, by January 1, the Earth's velocity toward the Sun is nearly zero before it starts traveling away from the Sun again. This is how Ponytail ended up with the "suspiciously" small value of 65 miles per hour.
| + | ==Transcript== |
| | + | {{incomplete transcript|Do NOT delete this tag too soon.}} |
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| − | On the other hand, by April 3, 2023, Earth will be receding from the Sun by almost 500 meters per second or 1800 kilometers per hour, which is a less normal speed for the average person to encounter in everyday life{{citation needed}}. | + | Ponytail: "…And we need to correct for our elliptical orbit. On January 1st, Earth will be approaching the sun at a rate of…let's see… |
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| − | 65 miles per hour is approximately equal to 105 kilometers per hour, although the even more typical scientific value (in {{w|International System of Units|SI}} derived units) would be 29 meters per second. | + | 65 miles per hour. |
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| − | The title text makes a joke by reversing the typical cat behavior of [[729: Laser Pointer|chasing laser pointer dots]] by envisioning a cat with a mass equivalent to 12 solar masses. The {{w|Schwarzschild radius}} for an object of that mass would be around 36 kilometers, so a cat-sized object of that mass would be a black hole, and would therefore bend all nearby light (including that from the laser) inwards towards its singularity. But then it should also draw in the physical laser pointer device itself, if it is neither very far away nor in orbit.
| + | Weird. Okay." |
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| − | ==Transcript==
| + | Cueball: "Weird?" |
| − | :[Ponytail is standing in front of a whiteboard writing on it with a pen, while Cueball looks over her shoulder from behind her. On the board is an almost circular ellipse with a cross that centers on a dot towards the left side of it. On the right side there is a small circle on the ellipse's line. There are several lines of wiggles representing unreadable text. To the left of the ellipse there are two lines near the top of and four near at the bottom of the ellipse. Ponytail is writing a fifth line below these almost under the ellipse. At the bottom to the left there is a rectangular frame with a line of text beneath it and at the bottom left corner there is a line forming a half closed rectangle around two dots.] | + | |
| − | :Ponytail: …And we need to correct for our elliptical orbit. On January 1<sup>st</sup>, Earth will be approaching the sun at a rate of ...let's see...
| + | Ponytail: "I get suspicious whenever I see a normal number in astronomy. We're not supposed to have those. Feels wrong. |
| − | :Ponytail: 65 miles per hour.
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| − | :Ponytail: Weird. Okay.
| + | Scales should all be incomprehensible." |
| − | :Cueball: Weird?
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| | + | Earlier, at the vet: |
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| | + | Megan in coat: "Your cat weighs 12 lbs." |
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| | + | Ponytail: "Ridiculous, nothing weighs '12'. You must mean 10<sup>-20</sup>? or 10<sup>40</sup>?" |
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| − | :[Ponytail has turned towards Cueball, the pen is no longer in her hand and the white board is no longer shown.] | + | Megan: "Fine. Your cat weighs 3x10<sup>-30</sup> solar masses." |
| − | :Ponytail: I get suspicious whenever I see a normal number in astronomy. We're not supposed to have those. Feels wrong.
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| − | :Ponytail: Scales should all be incomprehensible.
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| − | :[Across the top of the next panel there is a label:]
| + | Ponytail: "Okay. Better." |
| − | :Earlier, at the vet:
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| − | :[Megan in a lab-coat raises her hand palm up towards an animal carrier cage standing on her desk. The cage has a handle and five air holes are at the top. Behind two of them something black inside the cage can be seen. Ponytail is standing on the other side of the desk looking at Megan.]
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| − | :Megan: Your cat weighs 12 lbs.
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| − | :Ponytail: Ridiculous, nothing weighs "12". You must mean 10<sup>-20</sup>? Or 10<sup>40</sup>?
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| − | :Megan: Fine. Your cat weighs 3x10<sup>-30</sup> solar masses.
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| − | :Ponytail: Okay. Better.
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| | {{comic discussion}} | | {{comic discussion}} |
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| | [[Category:Comics featuring Cueball]] | | [[Category:Comics featuring Cueball]] |
| | [[Category:Comics featuring Ponytail]] | | [[Category:Comics featuring Ponytail]] |
| | + | [[Category:Astronomy]] |
| | [[Category:Comics featuring Megan]] | | [[Category:Comics featuring Megan]] |
| − | [[Category:Astronomy]]
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| − | [[Category:Cats]]
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