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3035: Trimix

2025-01-09T09:52:27Z

Complynx: wiki protestor

{{comic
| number = 3035
| date = January 8, 2025
| title = Trimix
| image = trimix_2x.png
| imagesize = 436x259px
| noexpand = true
| titletext = You don't want the nitrogen percentage to be too high or you run the risk of eutrophication.
}}

==Explanation==
{{incomplete|Created by a FLOATING TRIMIX SCUBA DIVER - Please change this comment when editing this page. Do NOT delete this tag too soon.}}
{{w|Trimix (breathing gas)|Trimix}} is a gas used in SCUBA tanks that consists of {{w|helium}}, {{w|oxygen}}, and {{w|nitrogen}}. Trimix comes in some standard ratios between the component gases, depending on the required diving depth, for example 21/35/44 (percentage oxygen/helium/nitrogen), 18/45/37 and 15/55/30 for increasing depth. Helium replaces a portion of the nitrogen to minimize nitrogen's narcotic effects at greater depths and to ease the effort required for breathing. This comic jokes that if the helium amount is too high, a diver will float away before reaching the water to start a dive, as a helium balloon will do if not securely tethered.

The reason a helium balloon creates lift is that it can inflate and a thin layer, that weighs almost nothing - the balloon tissue, thus can take up a large volume with low density gas inside. A SCUBA tank is made of metal, is heavy and cannot inflate{{Citation needed}} (it can only get to a point where there is too much pressure inside, and if it cannot be released via a valve, it will explode.) Thus it will never be able to create any kind of lift, no matter the amount of helium or any other gas that is compressed inside of it.

For a standard SCUBA tank to serve as a helium balloon capable of lifting a human diver of average size (not counting extra mass from dive accoutrements such as weight belts), it would need to contain approximately 70 kg of pure helium. This loading is more than an order of magnitude greater than the norm of around 3 kg of gas. It might prove difficult to fit such a tank with a regulator that could deliver the gas evenly and safely, and the absence of oxygen could be detrimental to the diver. Moreover, it would cost on the order of US$2000-4000 to charge the tank, an extra financial burden on an already expensive operation. Consider also that, at a mere 10 atm pressure, the density of helium is greater than that of air, hence a fixed-wall helium-containing tank at that density won't float. Normally-loaded SCUBA tanks are around 150 atm pressure, with a correspondingly higher density of the contained gas, and correspondingly lower likelihood that the tank will float. For these reasons, SCUBA divers floating in air are seldom encountered, the helium content of their tanks notwithstanding.

More to the point, the rise into the air would be caused by Archimede's force, which is proportional to the weigh of the displaced volume. Air being ~ 1,3 g/L, it takes 1m3 to lift 1,3kg, and ~50m3 to lift a 65kg person. Such a volume represents a 2.3m radius sphere, which is obviously way bigger than the helium tank.

The real reason SCUBA divers need to be careful with the amount of helium is to not get too little oxygen or too much nitrogen.

The title text asserts that a trimix diver whose gas mix contains an excess of nitrogen runs "the risk of eutrophication". The term {{w|Eutrophication|eutrophication}} describes the process by which nutrients ("fertilizers") accumulate in an environment, typically a body of water, leading to consequences that are often unfortunate for inhabitants or users of that environment. The human body is an ecosystem, but one that is not typically subject to eutrophication due to its manner of acquiring and jettisoning nutrients. Moreover, the nitrogen in trimix is diatomic elemental nitrogen, not the {{w|Nitrogen_fixation|"fixed"}} nitrogen that serves as a component of eutrophication. The diver would not breathe "fixed" nitrogen unless nitrogen-fixing bacteria were somehow incorporated into the SCUBA gear, a complex feature of dubious utility.

[[Randall]] addressed the question "how much helium is needed to lift a human body" in a [https://what-if.xkcd.com/62/ What if?] article. Helium has also featured in comics [https://xkcd.com/2766/ 2766] and [https://xkcd.com/2972/ 2972].

==Transcript==
:[In a single frame five images of Cueball is shown as a kind of carton, with each image a later time in the process. The first image to the left shows Cueball standing by the shore of a body of water. He is wearing SCUBA gear, goggles, breathing tubes, SCUBA tanks with a small H logo on it on his back, and swimming flippers, which almost touch the water.]

:[In the next four images he has the same equipment on, but with changes. It should be seen as he is still at the edge of the water, but that is not drawn in the next four depictions of Cueball.]

:[In the second image to the right of the first, Cueball's SCUBA tank is beginning to float upwards, so the end that is not teetered to Cueball move out and up, as shown with three small lines beneath the tank.]

:[In the third image the SCUBA tank is now floating above Cueball's head and the strings pull his arms a bit upwards. Cueball has turned his head looking up at the tank floating above and behind his head. Again three small lines beneath the tank indicates it is moving upwards.]

:[In the fourth image Cueball is now being lifted up, so his feet are now off the ground and he is tilting forward. The tank is now pointing it's bottom almost straight up and Cueball is looking down with his arms out the each side as the tank pulls him up. Two lines on either side of the tank indicate that it now wobbles above him as it lifts him up.]

:[In the fifth and last image the SCUBA tank is now pulling a dangling Cueball high above the ground, above his head's height in the first image. The tank is now turned so it points it's bottom to the left with lines on either side indicating wobbling motion. Cueball is floating as lying prone a bit bended on the middle as the tanks straps pulls him up. At this point he yells:]
:Cueball: ''Help!''

:[Caption below the panel:]
:Trimix SCUBA divers need to be careful not to let the helium percentage get too high.

{{comic discussion}}

[[Category:Comics featuring Cueball]]

2004: Sun and Earth

2018-06-08T11:47:13Z

Complynx: /* Transcript */

{{comic
| number = 2004
| date = June 8, 2018
| title = Sun and Earth
| image = sun_and_earth.png
| titletext = But we don't need to worry about the boiling masses sandwiching the thin layer in which we live, since we're so fragile and short-lived that it's unlikely to kill us before something else does! Wait, why doesn't that sound reassuring?
}}

==Explanation==
{{incomplete|Created by a hurried VOLCANO - Lots of things missing: (1) links (2) description of how the Sun is a massive convective system (3) description of how the Earth is a massive convective system (4) probably reword everything}}

This is one of a number of comics which describe everyday events in unusual terms, making them sound really weird. In this case, both the Sun and the Earth are "massive convective systems" blasting "huge plumes of heat", which contrasts sharply with the daily idea of the Sun being a ball in the sky and the Earth the thing under our feet.

In fact, the {{w|Sun}} does produce great amounts of light and heat and blasts it towards us, which is why we can live on Earth. Also, the {{w|Earth#Internal_structure|Earth's interior}} is very hot, occasionally causing {{w|volcano}} eruptions, which are also huge blasts of heat.

This could sound like a very bad scenario, however the title text reminds us that the real scenario we live in is far worse, as we are not likely to die from a Sun blast or volcano eruption.

This comic was likely inspired by the recent eruptions of the {{w|Kīlauea}} and {{w|Volcán de Fuego}}. In contrast, solar activity is currently low, because the {{w|Sunspot#Solar_cycle|sunspot solar cycle}} is in the low end of the 11-year cycle.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}
:Sun
:[Two arrows pointing to the Earth and the Sun with a caption:]
:Massive convective systems which occasionally blast huge plumes of heat at us without warning through mechanisms we cant directly observe and dont really understand.

:[Cueball and Meghan standing on the surface of Earth]
:Cueball: What a nice day

:Earth

:Title text: But we don't need to worry about the boiling masses sandwiching the thin layer in which we live, since we're so fragile and short-lived that it's unlikely to kill us before something else does! Wait, why doesn't that sound reassuring?

{{comic discussion}}

1583: NASA Press Conference

2015-09-28T10:36:24Z

Complynx: Fixed the explanation of alt text

{{comic
| number = 1583
| date = September 28, 2015
| title = NASA Press Conference
| image = nasa_press_conference.png
| titletext = Why are we spending billions to ruin Mars with swarms of robots when Elon Musk has promised to ruin Mars for a FRACTION of the cost?
}}

==Explanation==
A reference to the Press Conference to be held by NASA on 28th September 2015, (the same day this comic is published), which promises to solve "The Mars Mystery", and possibly announce the discovery of water or Life on Mars.

The "questions" portion of the press conference is derailed by a reporter from a dubious news network, known only as "The News", asking irrelevant questions, including comparisons to other fields, and questions related to the Star Wars movie franchise. This causes the other reporters to forget their original questions, and join in, much to the dismay of the NASA Scientist.

The subtext refers to Elon Musk, suggested to [http://edition.cnn.com/2015/09/11/us/elon-musk-mars-nuclear-bomb-colbert-feat/ just bombing Mars].

==Transcript==
{{incomplete transcript}}
:[Cueball is standing at a podium with the NASA logo on it
:Cueball: That concludes the press conference.
:Cueball: Any questions?
:Cueball: Yes, you, From... it just says "The News"?
:[Beret Guy is standing in a crowd holding a microphone]
:Beret Guy: Hi! I have a microphone so I'm real loud now.
:Beret Guy: How does this Mars data compare to data from other fields?
:Beret Guy: Like medicine? Or sports?
:Cueball (offscreen): That question makes no sense.
:Beret Guy: If there's water on Mars is it ruined?
:Beret Guy: Or will it be okay when it dries out?
:Cueball (offscreen): Any ''other'' questions?
:[The shot zooms out]
:Beret Guy: What were those guys hassling Luke in the Mos Eisley Cantina trying to accomplish?
:Beret Guy: I felt like i was supposed to understand that.
:Cueball: Anyone ''else?''
:Ponytail: That's now my question, too.
:Megan: Were they just picking a fight?
:Ponytail: If so why did...

{{comic discussion}}

Talk:1583: NASA Press Conference

2015-09-28T10:33:15Z

Complynx:

I think the alt image text refers to the Elon Musk's idea of Mars colonization with nuclear bombs
[[User:This that|This that]] ([[User talk:This that|talk]]) 10:00, 28 September 2015 (UTC)
Yep! I suppose that too.--[[User:Complynx|Complynx]] ([[User talk:Complynx|talk]]) 10:33, 28 September 2015 (UTC)

Maybe this could be linked somewhere: http://waitbutwhy.com/2015/08/how-and-why-spacex-will-colonize-mars.html [[User:Elektrizikekswerk|Elektrizikekswerk]] ([[User talk:Elektrizikekswerk|talk]]) 10:27, 28 September 2015 (UTC)