1677: Contrails

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Astronomy (or "astrology" in British English) is the study of...
Title text: Astronomy (or "astrology" in British English) is the study of...

[edit] Explanation

Contrails (short for "condensation trails") are trails of vapor produced by aircraft exhaust, trailing the airplane. They are formed from water condensing on jet fuel exhaust particles, some impurities of which provide bases for ice crystals to accumulate on. Some can dissipate in minutes, but others can last for hours or even longer, depending on the temperature, relative humidity and wind conditions at that particular altitude. Long-lasting contrails is a sign of high relative humidity and may sometimes predict the formation of clouds and rain. The chemtrail conspiracy theory claims that contrails lasting unusually long are actually chemical or biological agents sprayed into the air for sinister purposes. There is no known evidence such a thing is happening.

Here, White Hat notices that there are a lot of contrails in the air. Cueball corrects him, saying that in American English, contrails are called chemtrails, which is incorrect.

This is a comic in the My Hobby series. Some of these comics involve Cueball giving misleading information about pedantic terms, such as 1405: Meteor. Another of these comics, 966: Jet Fuel, even mentions chemtrails, saying that they are made of mind-control agents carried on board the planes that make them. Later they were again mentioned in 1803: Location Reviews.

The title text includes a similar situation, implying that astronomy and astrology are synonymous, with astrology being the term used in British English. However, this is incorrect. Astronomy is the scientific study of things in outer space, like stars, planets, and galaxies, whereas astrology is a system that infers a person's personality and characteristics from those same things in outer space. Though both involve studying celestial objects, astrology is considered a pseudoscience rather than an empirical science.

The joke is that British English and American English use different terms to refer to the same object, and one can often learn new words for a simple thing. This, however is not the case in this comic; contrail and chemtrail do not refer to the same thing, the latter being only a subtype of the former. And it being xkcd, we can assume that chemtrail is a term that is frowned upon. Thus the comic states it as misinformation.

This new found hobby is developing to another hobby about spreading misinformation that was released less than two month after this: 1697: Intervocalic Fortition.

[edit] Transcript

[Cueball and a White Hat are walking. White Hat is looking up to the sky while Cueball, walking in front holds out one arm towards him.]
White Hat: Lots of contrails today.
Cueball: Oh, you must be from the UK. In American English it's "Chemtrail".
[Caption below the panel:]
My hobby: Spreading linguistic misinformation

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Aside: worst name ever for university department: Astronomy and Cosmology - it's almost as if they want people to make the association... 10:58, 6 May 2016 (UTC)

Love the title text, you can choose to laugh or take offence irrespective of where you call home. Which you do says more about you than the text. Toltec (talk) 11:41, 6 May 2016 (UTC)

Worth noting that 'contrails' is itself a North Americanism? 12:03, 6 May 2016 (UTC)

The final paragraph does not logically follow from the comic or from the explanation. He's hooking different pseudoscience terms on different cultures (astrology on the UK and chemtrails on the US) so the comic doesn't take a stance on which country's educational system is better or more prone to superstitions than the other. 15:04, 6 May 2016 (UTC)

I've always called them vapour trails (north west England) -- (talk) (please sign your comments with ~~~~)

I can tell. I didn't know the english even put a 'u' in 'vapor'. 17:34, 19 December 2016 (UTC)

🐍 Its Canadian usage as well. Rush has an album by that name, and a song titled, and referencing them in the lyrics. video These Are Not The Comments You Are Looking For (talk) 20:28, 7 May 2016 (UTC) (Can't figure out how to prevent the font from changing)

The comic reminded me of the Hungarian Phrasebook sketch from Monty Python - basically someone who enjoys causing confusion for its own sake between speakers of (in this case, slightly) different languages. 18:21, 6 May 2016 (UTC)Pat

I grew up (US Midwest then Northwest) calling them "plane tracks" (by extension from "train tracks," I suppose) and later, "jet trails." I don't think I've ever /heard/ (as opposed to read) either "chemtrails" or "contrails," but they're both far outside my normal areas of work/interest, that there never would have been a reason for them to come up or pass by. 19:01, 6 May 2016 (UTC)

For difference in vocabulary between British English and American English, see Lists of words having different meanings in American and British English JakubNarebski (talk) 17:44, 7 May 2016 (UTC)

Contrails is more of a technical term, I think. I grew up in the southeast and currently live in the midwest and I only ever hear them called jet trails or vapor trails, only rarely does someone say contrails, and they're usually fairly technical people. 02:34, 8 May 2016 (UTC)

Should we mention the alternate meanings of "Con", especially Confidence trick would seem relevant here. Condor70 (talk) 06:42, 9 May 2016 (UTC)

I don't think that's relevant at all, the term "contrail" as mentioned is from "condensation", i.e. "to condense". I don't think a full etymology is merited on this page. 17:33, 19 December 2016 (UTC)
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