3187: High Altitude Cooking Instructions - Revision history

Elektrizikekswerk: /* Explanation */ No reason for tag given. Explanation seems complete, removed tag.

2026-03-30T08:53:26Z

‎Explanation: No reason for <incomplete> tag given. Explanation seems complete, removed tag.

R128: /* Explanation */

2026-01-08T18:39:43Z

‎Explanation

BunsenH: real-world version

2026-01-06T15:08:41Z

real-world version

82.13.184.33: /* Explanation */

2026-01-06T10:11:44Z

‎Explanation

82.13.184.33: /* Explanation */

2026-01-06T10:09:40Z

‎Explanation

82.13.184.33: /* Explanation */

2026-01-06T10:07:33Z

‎Explanation

174.53.211.85: /* Explanation */

2026-01-03T13:44:55Z

‎Explanation

174.53.211.85: /* Explanation */

2026-01-03T13:42:00Z

‎Explanation

BunsenH: stuff about effects of pressure

2026-01-01T00:38:14Z

stuff about effects of pressure

KelOfTheStars!: /* Transcript */ added the further characters from top line

2025-12-31T21:33:04Z

‎Transcript: added the further characters from top line

← Older revision		Revision as of 08:53, 30 March 2026
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	==Explanation==		==Explanation==
−	~~{{incomplete\|This page was created by a crew member using the ISS food warmer. Don't remove this notice too soon.}}~~
	At very low air pressures, typical of higher altitudes, cooking involves extra complications. This was previously mentioned in [[2153: Effects of High Altitude]]. This comic imagines food preparation instructions with additional caveats specifically for high-altitude cooking. These types of instructions are relatively common in the real world for certain kinds of products, such as cake mixes, but the comic involves extreme extrapolation of the concept.		At very low air pressures, typical of higher altitudes, cooking involves extra complications. This was previously mentioned in [[2153: Effects of High Altitude]]. This comic imagines food preparation instructions with additional caveats specifically for high-altitude cooking. These types of instructions are relatively common in the real world for certain kinds of products, such as cake mixes, but the comic involves extreme extrapolation of the concept.

@@ Line 23: / Line 23: @@
 At an altitude of 250,000-450,000 ft (approximately 76-137 km), the instructions assume the user is partaking in some kind of controlled spaceflight. The "cooking instructions", therefore, are instead instructions for reentry; basically, telling the user "You can wait until you get home". Once back on the ground it tells you to use the sea level cooking instructions.
-In this range of altitudes, you are ''highly'' likely to actively be either on the way down or, perhaps, still on the way up to space; cooking shouldn't be your primary concern in either case. The air-launched {{w|North American X-15|X-15}} and the later {{w|SpaceShipOne}} ultimately 'flew' at around 350,000 ft, though (as with rockets, re-entry capsules or {{w|Project HARP|projectiles}}) there is no real capability to loiter at these altitudes, being well above even the unmanned balloon-flight record or that of any {{w|AeroVironment Helios Prototype#Records|sustained level flight}}. Only in the latter might you even expect to be a passenger — not too busy to enjoy a light pre-prepared snack — already cooked, as necessary, at ground level.
+In this range of altitudes, you are ''highly'' likely to actively be either on the way down or, perhaps, still on the way up to space; cooking shouldn't be your primary concern in either case. The air-launched {{w|North American X-15|X-15}} and the later {{w|SpaceShipOne}} ultimately 'flew' at around 350,000 ft, though (as with rockets, re-entry capsules or {{w|Project HARP|projectiles}}) there is no real capability to loiter at these altitudes, being well above even the unmanned balloon-flight record or that of any {{w|AeroVironment Helios Prototype#Records|sustained level flight}}. Only in the latter might you even expect to be a passenger — not too busy to enjoy a light pre-prepared snack — already cooked, as necessary, at ground level. Additionally, these altitudes are [https://www.freemars.org/jeff/speed/index.htm too low to orbit], being subject to high atmospheric drag.
 The title text goes a step further and assumes that the user is in orbit — specifically, on the {{w|International Space Station}} — at an altitude of 1,300,000-1,400,000 (396-426 km) (the ISS is between 413-422 km above Earth's surface). Anyone on an orbiting space station is presumably going to be there for an extended period, so they cannot wait until after they return to Earth for a meal, so the "cooking instructions" simply direct the user to someone who can show them how to use the on-board facilities. Even if the pressure is one atmosphere, cooking with boiling water in a microgravity environment (as one might experience on a free-falling space station) is likely not the best of ideas, so it's better to ask someone for directions.

@@ Line 11: / Line 11: @@
 ==Explanation==
 {{incomplete|This page was created by a crew member using the ISS food warmer. Don't remove this notice too soon.}}
-At very low air pressures, typical of higher altitudes, cooking involves extra complications. This was previously mentioned in [[2153: Effects of High Altitude]]. This comic imagines food preparation instructions with additional caveats specifically for high-altitude cooking.
+At very low air pressures, typical of higher altitudes, cooking involves extra complications. This was previously mentioned in [[2153: Effects of High Altitude]]. This comic imagines food preparation instructions with additional caveats specifically for high-altitude cooking. These types of instructions are relatively common in the real world for certain kinds of products, such as cake mixes, but the comic involves extreme extrapolation of the concept.
 As air pressure decreases, the boiling point of water also decreases. Such a pressure decrease would be caused by any increase in altitude, but the effect isn't usually significant except for locations that are high up on mountains or highly elevated plateaus. This has two major effects on food cooking. If the food is cooked by boiling in water, that will be happening at a lower temperature than usual. The lower temperature means that to fully cook the food, it will be necessary to cook it for longer than at sea level. Lower pressure means that water will evaporate more easily, and for foods that aren't being boiled, longer cooking times will also give any moisture in the food more time to evaporate. This would leave the food relatively dried out. In this case, it will be necessary to add more water to begin with, so that the amount of moisture left at the end of the cooking process is correct.

@@ Line 25: / Line 25: @@
 In this range of altitudes, you are ''highly'' likely to actively be either on the way down or, perhaps, still on the way up to space; cooking shouldn't be your primary concern in either case. The air-launched {{w|North American X-15|X-15}} and the later {{w|SpaceShipOne}} ultimately 'flew' at around 350,000 ft, though (as with rockets, re-entry capsules or {{w|Project HARP|projectiles}}) there is no real capability to loiter at these altitudes, being well above even the unmanned balloon-flight record or that of any {{w|AeroVironment Helios Prototype#Records|sustained level flight}}. Only in the latter might you even expect to be a passenger — not too busy to enjoy a light pre-prepared snack — already cooked, as necessary, at ground level.
-The title text goes a step further and assumes that the user is in orbit - specifically, on the {{w|International Space Station}} at an altitude of 1,300,000-1,400,000 (396-426 km) (The ISS is between 413-422 km above Earth's surface). Anyone on an orbiting space station is presumably going to be on that space station for an extended period, so they cannot wait until after they return to Earth for a meal, so the "cooking instructions" simply direct the user to someone who can show them how to use the on-board facilities. Even if the pressure is one atmosphere, cooking with boiling water in a microgravity environment (as one might experience on a free-falling space station) is likely not the best of ideas, so better ask someone for directions.
+The title text goes a step further and assumes that the user is in orbit — specifically, on the {{w|International Space Station}} — at an altitude of 1,300,000-1,400,000 (396-426 km) (the ISS is between 413-422 km above Earth's surface). Anyone on an orbiting space station is presumably going to be there for an extended period, so they cannot wait until after they return to Earth for a meal, so the "cooking instructions" simply direct the user to someone who can show them how to use the on-board facilities. Even if the pressure is one atmosphere, cooking with boiling water in a microgravity environment (as one might experience on a free-falling space station) is likely not the best of ideas, so it's better to ask someone for directions.
 Interestingly, ''just'' below the 1,300,000 feet limit, you may instead be able to ask a Taikonaut how to use their {{w|Tiangong space station#Food and personal hygiene|microwave or recently installed air-fryer}}.

@@ Line 21: / Line 21: @@
 While the first two sections are reasonable accommodations, given the lower boiling point of water under less pressure, for altitudes of 3,500-6,500 ft (1-2 km) and 6,500-9,500 ft (2-3 km), the instructions - as is typical for xkcd - soon veer into absurdity.
-At an altitude of 250,000-450,000 ft (approximately 76-137 km), the instructions assume the user is partaking in some kind of controlled spaceflight. The "cooking instructions", therefore, are instead instructions for reentry; basically, telling the user "You can wait until you get home". Once back on the ground it tells you to use the sea level cooking instructions. These are most likely the one that is written on the top part of the comic.
+At an altitude of 250,000-450,000 ft (approximately 76-137 km), the instructions assume the user is partaking in some kind of controlled spaceflight. The "cooking instructions", therefore, are instead instructions for reentry; basically, telling the user "You can wait until you get home". Once back on the ground it tells you to use the sea level cooking instructions.
-In this range of altitudes, you are ''highly'' likely to actively be either on the way down or, perhaps, still on the way up to space; cooking shouldn't be your primary concern in either case. The air-launched {{w|North American X-15|X-15}}, as did the later {{w|SpaceShipOne}}, ultimately 'flew' at around 350,000 ft, though (as with rockets, re-entry capsules or {{w|Project HARP|projectiles}}) there is no real capability to loiter at these altitudes, being well above even the unmanned balloon-flight record or that of any {{w|AeroVironment Helios Prototype#Records|sustained level flight}}. And only in the latter might you even expect to be a passenger, not too busy to enjoy a light pre-prepared snack — already cooked, as necessary, at ground level.
+In this range of altitudes, you are ''highly'' likely to actively be either on the way down or, perhaps, still on the way up to space; cooking shouldn't be your primary concern in either case. The air-launched {{w|North American X-15|X-15}} and the later {{w|SpaceShipOne}} ultimately 'flew' at around 350,000 ft, though (as with rockets, re-entry capsules or {{w|Project HARP|projectiles}}) there is no real capability to loiter at these altitudes, being well above even the unmanned balloon-flight record or that of any {{w|AeroVironment Helios Prototype#Records|sustained level flight}}. Only in the latter might you even expect to be a passenger — not too busy to enjoy a light pre-prepared snack — already cooked, as necessary, at ground level.
 The title text goes a step further and assumes that the user is in orbit - specifically, on the {{w|International Space Station}} at an altitude of 1,300,000-1,400,000 (396-426 km) (The ISS is between 413-422 km above Earth's surface). Anyone on an orbiting space station is presumably going to be on that space station for an extended period, so they cannot wait until after they return to Earth for a meal, so the "cooking instructions" simply direct the user to someone who can show them how to use the on-board facilities. Even if the pressure is one atmosphere, cooking with boiling water in a microgravity environment (as one might experience on a free-falling space station) is likely not the best of ideas, so better ask someone for directions.

@@ Line 14: / Line 14: @@
 As air pressure decreases, the boiling point of water also decreases. Such a pressure decrease would be caused by any increase in altitude, but the effect isn't usually significant except for locations that are high up on mountains or highly elevated plateaus. This has two major effects on food cooking. If the food is cooked by boiling in water, that will be happening at a lower temperature than usual. The lower temperature means that to fully cook the food, it will be necessary to cook it for longer than at sea level. Lower pressure means that water will evaporate more easily, and for foods that aren't being boiled, longer cooking times will also give any moisture in the food more time to evaporate. This would leave the food relatively dried out. In this case, it will be necessary to add more water to begin with, so that the amount of moisture left at the end of the cooking process is correct.
 People who live at high altitudes and cook frequently are often aware of the kinds of adjustments to instructions that they need to make to have their cooking come out "right", but it's useful to have the adjustments given explicitly. This is especially true for foods of a kind likely to be used by people who will be cooking at unfamiliar altitudes, such as dehydrated foods for backpackers and amateur explorers. This comes at a "cost" of giving non-high-altitude people more instructions to read, which can appear daunting at first glance, and occupying more space on the food's packaging, leaving less for pretty pictures or other inducements to buy the product. Or the instructions can be printed in a smaller font, making them harder to read for some users.
-At the top of this comic, there are a part of these instructions that can only partly be seen; presumably, these are the "sea level" instructions mentioned later. What can be seen for sure is "remove from" and "for 3 minutes before serving." A qualified guess is that it says "remove from heat and let stand for 3 minutes before serving," but as nothing above this is visible, it is impossible to tell what the meal is, and the original cook time and temperature can only be guessed at. Below follows the separate High Altitude version, which list instructions for three different heights above sea level.
+At the top of this comic, there are a part of these instructions that can only partly be seen; presumably, these are the "sea level" instructions. What can be seen for sure is "remove from" and "for 3 minutes before serving." A qualified guess is that it says "remove from heat and let stand for 3 minutes before serving," but as nothing above this is visible, it is impossible to tell what the meal is, and the original cook time and temperature can only be guessed at. Below follows the separate High Altitude version, which lists instructions for three different heights above sea level.
 While the first two sections are reasonable accommodations, given the lower boiling point of water under less pressure, for altitudes of 3,500-6,500 ft (1-2 km) and 6,500-9,500 ft (2-3 km), the instructions - as is typical for xkcd - soon veer into absurdity.

@@ Line 15: / Line 15: @@
 As air pressure decreases, the boiling point of water also decreases. Such a pressure decrease would be caused by any increase in altitude, but the effect isn't usually significant except for locations that are high up on mountains or highly elevated plateaus. This has two major effects on food cooking. If the food is cooked by boiling in water, that will be happening at a lower temperature than usual. The lower temperature means that to fully cook the food, it will be necessary to cook it for longer than at sea level. Lower pressure means that water will evaporate more easily, and for foods that aren't being boiled, longer cooking times will also give any moisture in the food more time to evaporate. This would leave the food relatively dried out. In this case, it will be necessary to add more water to begin with, so that the amount of moisture left at the end of the cooking process is correct.
-A part of these instructions is thus labeled ''High Altitude Cooking Instructions'', probably on the back of the food package given the limited view we have of it. These particular instructions are relatively common in the real world for certain kinds of products, such as cake mixes. Other alternative times are also often given for different means of preparing food, such as with ovens, stove-top cooking, and microwave ovens (of specified power).<!-- e.g. "HEATING INSTRUCTIONS // HOB: Empty chili into a saucepan. Heat gently, stirring occasionally until piping hot. // MICROWAVE: Empty into a microwavable bowl, cover loosely. Cook on high (100%). // [Table] Cat D 750W : 4 mins / Cat E 850W 3½ mins // Stir halfway through cooking and before serving. // Microwave ovens vary. // The following[sic!] is a guide only." -->
+A part of these instructions is thus labeled ''High Altitude Cooking Instructions'', probably on the back of a food package. These types of instructions are relatively common in the real world for certain kinds of products, such as cake mixes. Alternative times are also often given for different means of preparing food, such as with ovens, stove-top cooking, and microwave ovens (of specified power).<!-- e.g. "HEATING INSTRUCTIONS // HOB: Empty chili into a saucepan. Heat gently, stirring occasionally until piping hot. // MICROWAVE: Empty into a microwavable bowl, cover loosely. Cook on high (100%). // [Table] Cat D 750W : 4 mins / Cat E 850W 3½ mins // Stir halfway through cooking and before serving. // Microwave ovens vary. // The following[sic!] is a guide only." -->
 People who live at high altitudes and cook frequently are often aware of the kinds of adjustments to instructions that they need to make to have their cooking come out "right", but it's useful to have the adjustments given explicitly. This is especially true for foods of a kind likely to be used by people who will be cooking at unfamiliar altitudes, such as dehydrated foods for backpackers and amateur explorers. This comes at a "cost" of giving non-high-altitude people more instructions to read, which can appear daunting at first glance, and occupying more space on the food's packaging, leaving less for pretty pictures or other inducements to buy the product. Or the instructions can be printed in a smaller font, making them harder to read for some users.

@@ Line 13: / Line 13: @@
 At very low air pressures, typical of higher altitudes, cooking experiences extra complications. This was previously mentioned in [[2153: Effects of High Altitude]]. This comic imagines food preparation instructions with additional caveats specifically for high-altitude cooking.
-As air pressure decreases, the boiling point of water also decreases. A decrease in pressure will occur due an increase of altitude, but the effect isn't usually significant (and also more so than weather-related variations, even in the exact same position, over time) except for locations that are particularly high up on mountains or mountainous plateaus. This has two major effects on food cooking. If the food is cooked by boiling in water, that will be happening at a lower temperature than usual. To fully cook the food, it will be necessary to cook it for longer than usual, for more time in water that isn't providing the usual rate of heat as it would at sea level, even as the water more quickly boils off. For foods that aren't being boiled, any moisture in the food will also evaporate more easily, which would leave the food relatively dried out unless it starts off more hydrated. In both cases, it will be necessary to add water (or more water than you'd normally be adding) to begin with, so that the amount of water is sufficient to complete the high-altitude cooking process safisfactorally.
+As air pressure decreases, the boiling point of water also decreases. Such a pressure decrease would be caused by any increase in altitude, but the effect isn't usually significant except for locations that are high up on mountains or highly elevated plateaus. This has two major effects on food cooking. If the food is cooked by boiling in water, that will be happening at a lower temperature than usual. The lower temperature means that to fully cook the food, it will be necessary to cook it for longer than at sea level. Lower pressure means that water will evaporate more easily, and for foods that aren't being boiled, longer cooking times will also give any moisture in the food more time to evaporate. This would leave the food relatively dried out. In this case, it will be necessary to add more water to begin with, so that the amount of moisture left at the end of the cooking process is correct.
-A part of these instructions is thus labeled ''High Altitude Cooking Instructions'', upon the packet, probably on the back with the limited view we have of it not including any particular branding, ingredients or any other clue as to what this particular food is within if. Such additional instructions are relatively common in the real world for certain kinds of products, such as alternative times to prepare from ovens, fan-assisted ovens, cooking in a pan and microwaves of one or more ratings.<!-- e.g. "HEATING INSTRUCTIONS // HOB: Empty chilli into a saucepan. Heat gently, stirring occasionally until piping hot. // MICROWAVE: Empty into a microwavable bowl, cover loosely. Cook on high (100%). // [Table] Cat D 750W : 4 mins / Cat E 850W 3½ mins // Stir halfway through cooking and before serving. // Microwave ovens vary. // The following[sic!] is a guide only." -->
+A part of these instructions is thus labeled ''High Altitude Cooking Instructions'', probably on the back of the food package given the limited view we have of it. These particular instructions are relatively common in the real world for certain kinds of products, such as cake mixes. Other alternative times are also often given for different means of preparing food, such as with ovens, stove-top cooking, and microwave ovens (of specified power).<!-- e.g. "HEATING INSTRUCTIONS // HOB: Empty chili into a saucepan. Heat gently, stirring occasionally until piping hot. // MICROWAVE: Empty into a microwavable bowl, cover loosely. Cook on high (100%). // [Table] Cat D 750W : 4 mins / Cat E 850W 3½ mins // Stir halfway through cooking and before serving. // Microwave ovens vary. // The following[sic!] is a guide only." -->
-People who live at high altitudes and cook frequently are often aware of the kinds of adjustments to instructions that they need to make to have their cooking come out "right", but it's useful to have the adjustments given explicitly, especially with foods that may be supplied specifically to mountaineering expeditions that may wish to cook the same product at various points between the foothills and a summit top. This comes at a "cost" of giving non-high-altitude people more instructions to read, which can appear daunting at first glance, and occupying more space on the food's packaging, leaving less for pretty pictures or other inducements to buy the product. Or the instructions can be printed in a smaller font, making them harder to read for some users.
+People who live at high altitudes and cook frequently are often aware of the kinds of adjustments to instructions that they need to make to have their cooking come out "right", but it's useful to have the adjustments given explicitly. This is especially true for foods of a kind likely to be used by people who will be cooking at unfamiliar altitudes, such as dehydrated foods for backpackers and amateur explorers. This comes at a "cost" of giving non-high-altitude people more instructions to read, which can appear daunting at first glance, and occupying more space on the food's packaging, leaving less for pretty pictures or other inducements to buy the product. Or the instructions can be printed in a smaller font, making them harder to read for some users.
-At the top there are a part of these instructions that can only partly be seen; presumably, these are the "sea level" instructions mentioned later. What can be seen for sure is "remove from" and "for 3 minutes before serving." A qualified guess is that it says "remove from heat and let stand for 3 minutes before serving," but as nothing above this is visible, it is impossible to tell what the meal is, and the original cook time and temperature can only be guessed at. Below follows the separate High Altitude version, which list instructions for three different heights above sea level.
+At the top of this comic, there are a part of these instructions that can only partly be seen; presumably, these are the "sea level" instructions mentioned later. What can be seen for sure is "remove from" and "for 3 minutes before serving." A qualified guess is that it says "remove from heat and let stand for 3 minutes before serving," but as nothing above this is visible, it is impossible to tell what the meal is, and the original cook time and temperature can only be guessed at. Below follows the separate High Altitude version, which list instructions for three different heights above sea level.
 While the first two sections are reasonable accommodations, given the lower boiling point of water under less pressure, for altitudes of 3,500-6,500 ft (1-2 km) and 6,500-9,500 ft (2-3 km), the instructions - as is typical for xkcd - soon veer into absurdity.

@@ Line 37: / Line 37: @@
 :[The readable part of the top note's two lines:]
-:Remove fro...
+:Remove fro[m heat]
 :for 3 minutes before serving.