Difference between revisions of "1752: Interplanetary Experience"

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| Pluto, Moon, Mercury || Night || Mt. Everest at night || Pluto, Moon and Mercury are relatively small, rocky bodies with practically no atmosphere and relatively slow rotation. Therefore their surfaces not illuminated by Sun will cool down to very low temperatures (around -170 °C, -290 °F, 100 K), making their nighttime hemispheres desolate, dark and cold places. Randall proposes the summit of Mt. Everest as the place on Earth that will emulate the conditions most closely. It is a rocky, desolate and cold place. Even though it is not the coldest place on Earth, it is the highest point on land, therefore it has the lowest atmospheric pressure. It cannot be compared to the near-zero pressure and 100 Kelvins conditions on the aforementioned bodies, but it is as close as you can get on Earth. The top of Mt. Everest has an air pressure just 1/3 of what it is at sea level, and the oxygen levels are so low that they are barely survivable ([http://adventureblog.nationalgeographic.com/2016/04/21/how-climbing-everest-without-oxygen-can-go-very-wrong/ a few people have reached the top without oxygen tanks, but others have died after losing their supply]), making it as close as you can get on Earth to the near-vacuum found on these worlds.
 
| Pluto, Moon, Mercury || Night || Mt. Everest at night || Pluto, Moon and Mercury are relatively small, rocky bodies with practically no atmosphere and relatively slow rotation. Therefore their surfaces not illuminated by Sun will cool down to very low temperatures (around -170 °C, -290 °F, 100 K), making their nighttime hemispheres desolate, dark and cold places. Randall proposes the summit of Mt. Everest as the place on Earth that will emulate the conditions most closely. It is a rocky, desolate and cold place. Even though it is not the coldest place on Earth, it is the highest point on land, therefore it has the lowest atmospheric pressure. It cannot be compared to the near-zero pressure and 100 Kelvins conditions on the aforementioned bodies, but it is as close as you can get on Earth. The top of Mt. Everest has an air pressure just 1/3 of what it is at sea level, and the oxygen levels are so low that they are barely survivable ([http://adventureblog.nationalgeographic.com/2016/04/21/how-climbing-everest-without-oxygen-can-go-very-wrong/ a few people have reached the top without oxygen tanks, but others have died after losing their supply]), making it as close as you can get on Earth to the near-vacuum found on these worlds.
 
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| Moon || Day || Mt. Everest at noon under a tanning lamp || As explained above, Mt. Everest is as good emulation of Moon surface at night as you can get. During the Moon's day, its surface gets about as much Sun's radiation as Earth, because both bodies' distance from the Sun is almost the same. The Earth's atmosphere, however, stops most of the Sun's ultraviolet radiation. A {{w|tanning lamp}} is a device emitting mostly ultraviolet radiation for the purpose of artificial {{w|tanning}}; here it is used to augment the filtered Sun's radiation in an attempt to emulate Moon's daytime conditions better.
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| Moon || Day || Mt. Everest at noon under a tanning lamp || As explained above, Mt. Everest is as good emulation of Moon surface at night as you can get. During the Moon's day, its surface gets about as much Sun's radiation as Earth at noon, because both bodies' distance from the Sun is almost the same. The Earth's atmosphere, however, stops most of the Sun's ultraviolet radiation. A {{w|tanning lamp}} is a device emitting mostly ultraviolet radiation for the purpose of artificial {{w|tanning}}; here it is used to augment the filtered Sun's radiation in an attempt to emulate Moon's daytime conditions better.
 
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| Mercury || Day || A lava flow at a volcano at noon || Mercury never quite reaches lava temperatures (if it did, its surface would be molten), but it gets close. At noon, Mercury's equator reaches 420°C (800°F, 700 K) - depending on what type of rock it's formed from, [http://hvo.wr.usgs.gov/volcanowatch/archive/2003/03_04_17.html lava can erupt] at 500°C-600°C (930°F-1100°F, 770-870 K). Standing on a partially solidified lava flow (which, it goes without saying, is incredibly dangerous) would expose you to similar temperatures. Close to the North Pole, Mercury is around 100°C (230°F, 380 K).
 
| Mercury || Day || A lava flow at a volcano at noon || Mercury never quite reaches lava temperatures (if it did, its surface would be molten), but it gets close. At noon, Mercury's equator reaches 420°C (800°F, 700 K) - depending on what type of rock it's formed from, [http://hvo.wr.usgs.gov/volcanowatch/archive/2003/03_04_17.html lava can erupt] at 500°C-600°C (930°F-1100°F, 770-870 K). Standing on a partially solidified lava flow (which, it goes without saying, is incredibly dangerous) would expose you to similar temperatures. Close to the North Pole, Mercury is around 100°C (230°F, 380 K).

Revision as of 10:57, 28 October 2016

Interplanetary Experience
But instead of hitting the ocean, you should land in an overheating hot tub on a sinking cruise ship, sending it crashing through the floor into the burning engine room as the ship goes under.
Title text: But instead of hitting the ocean, you should land in an overheating hot tub on a sinking cruise ship, sending it crashing through the floor into the burning engine room as the ship goes under.

Explanation

Table of celestial bodies and like Earth places

Body(ies) Day/Night Place on Earth Explanation
Pluto, Moon, Mercury Night Mt. Everest at night Pluto, Moon and Mercury are relatively small, rocky bodies with practically no atmosphere and relatively slow rotation. Therefore their surfaces not illuminated by Sun will cool down to very low temperatures (around -170 °C, -290 °F, 100 K), making their nighttime hemispheres desolate, dark and cold places. Randall proposes the summit of Mt. Everest as the place on Earth that will emulate the conditions most closely. It is a rocky, desolate and cold place. Even though it is not the coldest place on Earth, it is the highest point on land, therefore it has the lowest atmospheric pressure. It cannot be compared to the near-zero pressure and 100 Kelvins conditions on the aforementioned bodies, but it is as close as you can get on Earth. The top of Mt. Everest has an air pressure just 1/3 of what it is at sea level, and the oxygen levels are so low that they are barely survivable (a few people have reached the top without oxygen tanks, but others have died after losing their supply), making it as close as you can get on Earth to the near-vacuum found on these worlds.
Moon Day Mt. Everest at noon under a tanning lamp As explained above, Mt. Everest is as good emulation of Moon surface at night as you can get. During the Moon's day, its surface gets about as much Sun's radiation as Earth at noon, because both bodies' distance from the Sun is almost the same. The Earth's atmosphere, however, stops most of the Sun's ultraviolet radiation. A tanning lamp is a device emitting mostly ultraviolet radiation for the purpose of artificial tanning; here it is used to augment the filtered Sun's radiation in an attempt to emulate Moon's daytime conditions better.
Mercury Day A lava flow at a volcano at noon Mercury never quite reaches lava temperatures (if it did, its surface would be molten), but it gets close. At noon, Mercury's equator reaches 420°C (800°F, 700 K) - depending on what type of rock it's formed from, lava can erupt at 500°C-600°C (930°F-1100°F, 770-870 K). Standing on a partially solidified lava flow (which, it goes without saying, is incredibly dangerous) would expose you to similar temperatures. Close to the North Pole, Mercury is around 100°C (230°F, 380 K).
Venus A heat-shrink wetsuit in a blast furnace The average surface temperature on Venus is around 470°C (870°F, 740 K), and the pressure is 92 bar (by comparison, pressure on earth is only about 1 bar). A blast furnace is a bit too hot - the blast itself is 900 °C to 1300 °C (1600 °F to 2300 °F), and they can reach 2000 °C - but either temperature is enough to kill you in seconds. As the blast furnace would emulate Venus temperature but not pressure, Randall proposes a daring volunteer shall wear a hypothetical heat-shrink wetsuit. A wetsuit is an elastic garment worn mostly over the whole body by swimmers, divers etc. Heat-shrink tubing is a tube made of a material that shrinks when heated, used to provide extra insulation and mechanical or environmental protection in electrical and electronics work - you put a length of tubing over your wire, connector, or a joint and heat it with hot air gun, making it shrink and crimp over your device. A hypothetical heat-shrink wetsuit worn while sitting in a blast furnace supposedly would shrink rapidly in the extreme temperature, extorting great pressure on your body, thus emulating Venus surface atmospheric pressure.
Mars Mt. Everest at sunset Again, thin atmosphere and very cold temperatures, but Mars's dusty, greenhouse-gas-containing atmosphere means it's not as cold as Mercury at night, nor as hot as the Moon during the day. The sunset will also make the sky reddish-purple, similar to the way the Martian sky often looks.
Titan Waist-deep in an outgassing Siberian swamp Titan is one of the promising worlds for life - given that its surface temperature is −180°C (−290°F, 95 K), that says a lot about how inhospitable the rest of the solar system is. The chemistry of the planet is interesting - there are lots of nitrogen compounds and hydrocarbons, and the atmosphere is mostly nitrogen and methane. Similar compounds are produced by rotting material in swamps, hence the comparison. One key difference though is that on Earth, swamps are mostly water. On Titan, they're liquid methane. Siberia also has some of the most extreme temperature differences on Earth, while Titan is just consistently cold. Randall is presumably referencing Siberia's Pole of Cold, the coldest point in the Northern hemisphere having reached −71.2 °C (−96.2 °F). Not quite Titan levels of cold, but certainly deadly enough.
Jupiter, Saturn, Uranus, Neptune Jumping from a high-altitude balloon over an Antarctic Ocean winter storm (title text: and landing in an overheating hot tub on a sinking cruise ship, sending it crashing through the floor into the burning engine room as the ship goes under.) They're called gas giants for a reason. All the planets have stormy weather (Uranus is the least active, and Neptune is the most active) and a very dramatic temperature and pressure gradient. On the edge of the atmosphere, conditions aren't much different to space, but as you fall in, the temperature and pressure rapidly increases past freezing point (allowing clouds of ice and water), past boiling point, and up to thousands of degrees until you reach the core of superheated iron and nickel. Being inside a burning metal ship crushed by the water pressure of the deep ocean is the closest imaginable representation of the pressure, but in fact the cores of these planets are far, far more inhospitable than that - Jupiter is so hot and high-pressure that hydrogen becomes a metal.

Transcript

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Discussion

The Mars at sunset might also be reference to "alpenglow." A simple Google of "alpenglow" should suffice as explanation 172.68.54.126 (talk) (please sign your comments with ~~~~)


The explanation starts out saying that this list includes all the other planets in our system as well as a couple moons, however uranus and saturn are clearly left off the list. 108.162.238.37 15:16, 28 October 2016 (UTC)

Retracted, I did not understand the hypen in the last line. 172.68.78.125 16:18, 28 October 2016 (UTC)

Actually, the upper atmosphere of Venus has Earthlike temperature and Earthlike pressure - it is, indeed, pretty much the only planetary location in the Solar System safer enough than deep space to be worth the gravity well (you need a balloon to keep you aloft, oxygenated air, and protection from the sulfuric acid, but Earth air is a lifting gas on Venus so the first two solve each other). So "do not go to Venus" and "nowhere is even close to survivable except Earth" aren't quite true. The surface of Venus is absurdly inhospitable even to machines, but one shouldn't write off the whole planet so quickly. Magic9mushroom (talk) 04:02, 29 October 2016 (UTC)

I definitely think the part about Venus atmosphere is not only hot and dense, but also highly corrosive is worth mentioning. Sulfuric acid, phosphoric acid ... -- Hkmaly (talk) 17:53, 29 October 2016 (UTC)


This could also be a reference to the short movie Wanderers by Erik Wernquist and narrated by Carl Sagan. In the movie we can see imaginary scenes where humans are trekking the solar system for personal exploration. /LordSillion - https://vimeo.com/108650530 162.158.134.178 04:21, 11 January 2017 (UTC)

Someone who is good at this kind of things should also change the transcript to get rid of the table. --Lupo (talk) 12:16, 18 January 2019 (UTC)