Difference between revisions of "2524: Comet Visitor"

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When a long-period comet comes into the inner Solar System, it's often figuratively called a "visit". But Megan and Cueball treat this more literally. Just as one usually neatens up their home when they're expecting guests, to make a good impression, they realize they need to clean up the Earth and its vicinity in preparation for this "visitor". Cueball starts handing out assignments -- he'll clean up the {{w|Pacific Garbage Patch}}, and suggests that Megan take care of all the debris in orbit. It's also common to put some useful objects out of view without throwing them away (perhaps to prevent someone damaging them), planning on returning them to their normal place after the visit; Cueball suggests doing this with the Mars rovers. And he suggests sweeping up the footprints that NASA astronauts left on the Moon during the Apollo missions. However, since the comet will never be anywhere near Earth and Mars, all this hardly seems necessary; it would be like cleaning up your home because the President or some other dignitary will be somewhere in the same metropolitan area. Furthermore, sweeping footprints in the Moon, that Cueball sees as a way of tidying up, would be seen as [https://www.smithsonianmag.com/science-nature/nasa-looks-to-protect-historic-sites-on-the-moon-47186092/ destroying an invaluable archaeological sites by NASA and other people].
 
When a long-period comet comes into the inner Solar System, it's often figuratively called a "visit". But Megan and Cueball treat this more literally. Just as one usually neatens up their home when they're expecting guests, to make a good impression, they realize they need to clean up the Earth and its vicinity in preparation for this "visitor". Cueball starts handing out assignments -- he'll clean up the {{w|Pacific Garbage Patch}}, and suggests that Megan take care of all the debris in orbit. It's also common to put some useful objects out of view without throwing them away (perhaps to prevent someone damaging them), planning on returning them to their normal place after the visit; Cueball suggests doing this with the Mars rovers. And he suggests sweeping up the footprints that NASA astronauts left on the Moon during the Apollo missions. However, since the comet will never be anywhere near Earth and Mars, all this hardly seems necessary; it would be like cleaning up your home because the President or some other dignitary will be somewhere in the same metropolitan area. Furthermore, sweeping footprints in the Moon, that Cueball sees as a way of tidying up, would be seen as [https://www.smithsonianmag.com/science-nature/nasa-looks-to-protect-historic-sites-on-the-moon-47186092/ destroying an invaluable archaeological sites by NASA and other people].
  
The title text debunks the claim that the {{w|Great Wall of China}} is the only human-made structure visible from outer space; in fact the Great Wall cannot easily be distinguished from space (as it is very long but not wide), but some other human constructions such as the Pyramids can (and cities are easily visible at night because they emit light).
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The title text debunks the claim that the {{w|Great Wall of China}} is the only [https://en.m.wikipedia.org/wiki/Artificial_structures_visible_from_space human-made structure visible from outer space]; in fact the Great Wall cannot easily be distinguished from space (as it is very long but not wide), but some other human constructions such as the Pyramids can (and cities are easily visible at night because they emit light).
  
 
==Transcript==
 
==Transcript==

Revision as of 13:32, 5 October 2021

Comet Visitor
It's a myth that the Great Wall of China is the only human-made structure visible from space--there are LOTS of structures for us to feel self-conscious about!
Title text: It's a myth that the Great Wall of China is the only human-made structure visible from space--there are LOTS of structures for us to feel self-conscious about!

Explanation

Ambox notice.png This explanation may be incomplete or incorrect: Created by a PACIFIC MOON FOOT-PATCH - Please change this comment when editing this page. Do NOT delete this tag too soon.
If you can address this issue, please edit the page! Thanks.
Comet C/2014 UN271 is a large comet that was discovered in 2014 almost as far from the Sun as the orbit of Neptune, and it will reach its closest approach in 2031, near Saturn's orbit. It's an Oort Cloud comet, with a period of more than 4 million years. Since modern humans (homo sapiens) evolved about 300,000 years ago (although tool-making ancestors were around about 2.5 million years ago), the last time it was among the planets was long before humans evolved.

When a long-period comet comes into the inner Solar System, it's often figuratively called a "visit". But Megan and Cueball treat this more literally. Just as one usually neatens up their home when they're expecting guests, to make a good impression, they realize they need to clean up the Earth and its vicinity in preparation for this "visitor". Cueball starts handing out assignments -- he'll clean up the Pacific Garbage Patch, and suggests that Megan take care of all the debris in orbit. It's also common to put some useful objects out of view without throwing them away (perhaps to prevent someone damaging them), planning on returning them to their normal place after the visit; Cueball suggests doing this with the Mars rovers. And he suggests sweeping up the footprints that NASA astronauts left on the Moon during the Apollo missions. However, since the comet will never be anywhere near Earth and Mars, all this hardly seems necessary; it would be like cleaning up your home because the President or some other dignitary will be somewhere in the same metropolitan area. Furthermore, sweeping footprints in the Moon, that Cueball sees as a way of tidying up, would be seen as destroying an invaluable archaeological sites by NASA and other people.

The title text debunks the claim that the Great Wall of China is the only human-made structure visible from outer space; in fact the Great Wall cannot easily be distinguished from space (as it is very long but not wide), but some other human constructions such as the Pyramids can (and cities are easily visible at night because they emit light).

Transcript

Ambox notice.png This transcript is incomplete. Please help editing it! Thanks.
[Megan sits at a desk in front of a computer, looking to the left off-panel and pointing at the screen]
Megan: Have you seen this big comet, C/2014 UN271? It'll pass near Saturn's orbit in 10 years.
[Cueball stands behind Megan, who is now looking at the computer and typing]
Cueball: Wow, look at the orbital period.
Megan: Yeah, it hasn't been to this part of the solar system since humans evolved. At least.
[Cueball starts running off-panel, holding his finger in the air. Megan looks towards him with both arms resting on the back of her chair]
Cueball: Well, we definitely need to tidy up. I'll start on the Pacific Garbage Patch, you tackle orbital debris.
Megan: What about the moon footprints?
Cueball: Sweep them up. Collect the Mars rovers, too! We can put them back once it's gone.


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Discussion

Yup. nobody says that the Dinosaur Killer wasn't aliens saying "don't get cocky, lifeforms". Best to keep the head down. 141.101.99.82 06:53, 5 October 2021 (UTC)

AFAIK cosmonauts reported that the Great Wall of China actually isn't visible from space - it's too thin and blends in with the background. Though technically we can probably claim that everything visible on Google Satellite View qualifies as "visible from space"... 172.68.10.245 09:10, 5 October 2021 (UTC)

This somehow seems like the perfect setup for a "Your mom" joke.127.0.0.1 20:49, 7 October 2021 (UTC)
If it were satellite view all along. It's aerial view for the higher zoom levels. BTW, anything on Earth is visible from space, provided there's equipment with sufficient resolution, selectivity and sensitivity vs. distance. From Saturn, well, it needs truly alien equipment to see anything of concern, no big worries. Sweep it under the rug and smile. Send some hello's over Arecibo... ah, crap. -- 162.158.93.178 10:29, 5 October 2021 (UTC)

Should we also mention that the Great Pacific Garbage Patch isn't visible AT ALL, even to humans who might be swimming in it? From Wiki: Despite the common public perception of the patch existing as giant islands of floating garbage, its low density (4 particles per cubic meter) prevents detection by satellite imagery, or even by casual boaters or divers in the area. This is because the patch is a widely dispersed area consisting primarily of suspended "fingernail-sized or smaller bits of plastic", often microscopic, particles in the upper water column known as microplastics. mezimm 172.69.68.22 13:46, 5 October 2021 (UTC)

Although perhaps obvious, I feel like this is Randall trying to provide motivation to clean up the Earth (eg. Global warming and what not) in general, but making it kinda fun instead of doomsday scenarios. Might be useful to mention in body of explanation. Stephenjuniverse (talk) 14:00, 5 October 2021 (UTC)

Possibly, but it could also be prompted by the plan to deploy lots of Starlink satellites that interfere with astronomy. And increasing concern over all the space junk in orbit. We're just messy on many levels, like a teenager who never cleans up his room. Barmar (talk) 14:28, 5 October 2021 (UTC)
That's a fair point. Stephenjuniverse (talk) 14:20, 6 October 2021 (UTC)

Regarding the visibility of the Great Wall, it is possible that the chain of geographical significant boundary features (upon which the wall was built, beacause it was a convenient definable and defendable ribbon of terrain to make a claim over) are notably visible. As might other (unrelated, unWalled) geographies/geologies, but you're not looking at those bits 'imagining' you can see the Wall and seeing man-made patterns where there should be none. (Also, if settlements and/or transport links roughly hug one side or the other of the vague and intrinsically non-visible route, for historical or recent reasons, they might add 'relief' enhancement to the scene by whatever geophysical 'smudged marks' they display to the orbital viewer. A bit like Belgium's borders are made very visible at night due to the legislatedly ubiquitous street-lighting, compared to its neighbours, or North Korea by the inverse effect - but especially against its southern neighbour.) 141.101.77.69 18:28, 5 October 2021 (UTC)