Difference between revisions of "Atmosphere"

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* Very small [[world]]s, [[planetoid]]s, [[asteroid]]s, and other small objects almost never have an atmosphere unless artificially modified using advanced technology.  
 
* Very small [[world]]s, [[planetoid]]s, [[asteroid]]s, and other small objects almost never have an atmosphere unless artificially modified using advanced technology.  
 
* [[Tent World]]s are an example of a world ordinarily too small to contain an atmosphere, but artificially and technologically modified to possess an atmosphere using [[paraterraforming]].
 
* [[Tent World]]s are an example of a world ordinarily too small to contain an atmosphere, but artificially and technologically modified to possess an atmosphere using [[paraterraforming]].
−
+
 
 
== Description / Specifications==
 
== Description / Specifications==
 
Few worlds will be found where a single chemical makes up the entire atmosphere. Most atmospheres have a complex gas mix which will include a variety of specific elements, some in great amounts, while others are barely detectable. Atmospheric mixes include active and inert gases. On Earth, oxygen (02) is active, but forms less than 25% of the total atmosphere around us. Three times as much is nitrogen (N2), plus a few trace elements such as argon. These inert gases are not usually required by animal at plant life, and take no part in the chemical reactions essential for life (except for nitrogen, a special case). They are, nonetheless, part of the atmosphere. In this [[AAB]] article, when we refer to a specific gas such as methane making up an atmosphere, we are referring to the active element, which may make up only a fraction of the total atmospheric mix. {{Page cite|name=Exotic Atmospheres|page=3-4}}
 
Few worlds will be found where a single chemical makes up the entire atmosphere. Most atmospheres have a complex gas mix which will include a variety of specific elements, some in great amounts, while others are barely detectable. Atmospheric mixes include active and inert gases. On Earth, oxygen (02) is active, but forms less than 25% of the total atmosphere around us. Three times as much is nitrogen (N2), plus a few trace elements such as argon. These inert gases are not usually required by animal at plant life, and take no part in the chemical reactions essential for life (except for nitrogen, a special case). They are, nonetheless, part of the atmosphere. In this [[AAB]] article, when we refer to a specific gas such as methane making up an atmosphere, we are referring to the active element, which may make up only a fraction of the total atmospheric mix. {{Page cite|name=Exotic Atmospheres|page=3-4}}
−
 
+
−
=== Basic Atmosphere Types ===
 
−
The [[UWP]] atmosphere table, in use by the [[IISS]], indicates that there are nine basic main types of atmosphere: {{Page cite|name=The Universal World Profile|page=14}}
 
−
# [[Vacuum]]
 
−
# [[Trace Atmosphere|Trace]]
 
−
# [[Very Thin Atmosphere|Very Thin]]
 
−
# [[Thin Atmosphere|Thin]]
 
−
# [[Standard Atmosphere|Standard]]
 
−
# [[Dense Atmosphere|Dense]]
 
−
# [[Exotic Atmosphere|Exotic]]
 
−
# [[Corrosive Atmosphere|Corrosive]]
 
−
# [[Insidious Atmosphere|Insidious]]
 
−
 
 
−
'''''NOTE''''': They are listed in order of pressure and density.
 
−
 
 
−
=== Expanded Basic Atmosphere Types ===
 
−
Combinations of the below atmospheres may exist and are not comprehensively listed:
 
−
# [[Corrosive Atmosphere]]
 
−
# [[Dense Atmosphere]]
 
−
# [[Ellipsoid Atmosphere]]
 
−
# [[Exotic Atmosphere]]
 
−
# [[High Pressure Atmosphere]]
 
−
# [[High Temperature Atmosphere]]
 
−
# [[Insidious Atmosphere]]
 
−
# [[Low Pressure Atmosphere]]
 
−
# [[Low Temperature Atmosphere]]
 
−
# [[Standard Atmosphere]] (Tolerable pressure, temperature, constituent gases, etc. for [[Conventional Life|conventional]] [[lifeform]]s)
 
−
# [[Tainted Atmosphere]]
 
−
# [[Thin Atmosphere]]
 
−
# [[Trace Atmosphere]]
 
−
# [[Vacuum]] ([[Interstellar Medium]])
 
−
# [[Very Thin Atmosphere]]
 
−
 
 
−
'''''NOTE''''': They are listed in [[Anglic]] alphabetical order.
 
−
 
 
 
=== World Atmosphere Classification Codes Table ===
 
=== World Atmosphere Classification Codes Table ===
 
As a generality, small worlds are unable to maintain a sufficient gravity to maintain an atmosphere and tend to have thinner or trace atmospheres while larger worlds grow increasingly dense. Corrosive and insidious worlds tend to be at extreme ends of the tolerable temperature spectrum.  
 
As a generality, small worlds are unable to maintain a sufficient gravity to maintain an atmosphere and tend to have thinner or trace atmospheres while larger worlds grow increasingly dense. Corrosive and insidious worlds tend to be at extreme ends of the tolerable temperature spectrum.  
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| [[Vacuum]]   
 
| [[Vacuum]]   
 
| 0.10-0.42
 
| 0.10-0.42
−
| [[Very Thin Atmosphere|Very Thin]] requires a [[respirator]]. The atmosphere has a pressure of 0.1 to 0.42 atmospheres, which requires the use of a [[respirator]] to ensure sufficient oxygen.
+
| [[Very Thin Atmosphere|Very Thin]] requires a [[respirator]]. The atmosphere has a pressure of 0.1 to 0.42 atmospheres, which requires the use of a respirator to ensure sufficient oxygen.
 
|-
 
|-
 
| 4   
 
| 4   
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| [[Thin Atmosphere|Thin]]  
 
| [[Thin Atmosphere|Thin]]  
 
| 0.43-0.70
 
| 0.43-0.70
−
| [[Tainted Atmosphere|Tainted]] requires a [[filter mask]]. The atmosphere contains an unusual taint such as such as [[Diseases & Plagues of Charted Space|disease]], a hazardous gas mix, [[pollutant]]s, or sulfur compounds which requires the use of a [[filter mask]].  
+
| [[Tainted Atmosphere|Tainted]] requires a [[filter mask]]. The atmosphere contains an unusual taint such as such as disease, a hazardous gas mix, pollutants, or sulfur compounds which requires the use of a [[filter mask]].  
 
|-
 
|-
 
| 5   
 
| 5   
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| [[Thin Atmosphere|Thin]]  
 
| [[Thin Atmosphere|Thin]]  
 
| 0.43-0.70
 
| 0.43-0.70
−
| No survival gear required. The atmosphere has a pressure of 0 43 to 0.70 atmospheres. The atmosphere is a standard oxygen/nitrogen mix, which is breathable without assistance.
+
| The atmosphere has a pressure of 0 43 to 0.70 atmospheres. The atmosphere is a standard oxygen/nitrogen mix, which is breathable without assistance.
 
|-
 
|-
 
| 6   
 
| 6   
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| [[Standard Atmosphere|Standard]]  
 
| [[Standard Atmosphere|Standard]]  
 
| 0.71-1.49
 
| 0.71-1.49
−
| No survival gear required. The atmosphere has a pressure of 0.71 to 1.49 atmospheres. The atmosphere is a standard oxygen/nitrogen mix, which is breathable without assistance.
+
| The atmosphere has a pressure of 0.71 to 1.49 atmospheres. The atmosphere is a standard oxygen/nitrogen mix, which is breathable without assistance.
 
|-
 
|-
 
| 7   
 
| 7   
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| [[Dense Atmosphere|Dense]]  
 
| [[Dense Atmosphere|Dense]]  
 
| 1.50-2.49
 
| 1.50-2.49
−
| No survival gear required. The atmosphere has a pressure of 1.50 to 2.49 atmospheres The atmosphere is a standard oxygen/nitrogen mix, which is breathable without assistance.
+
| The atmosphere has a pressure of 1.50 to 2.49 atmospheres The atmosphere is a standard oxygen/nitrogen mix, which is breathable without assistance.
 
|-
 
|-
 
| 9  
 
| 9  
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| A (10)  
 
| A (10)  
 
| [[Exotic Atmosphere|Exotic]]
 
| [[Exotic Atmosphere|Exotic]]
−
| [[Exotic Atmosphere|Exotic]], Conventional   
+
| [[Exotic Atmosphere|Exotic]] , Conventional   
 
| varies
 
| varies
 
| An unusual gas mix which requires the use of [[oxygen tank]]s, but [[protective suit]]s are not needed.
 
| An unusual gas mix which requires the use of [[oxygen tank]]s, but [[protective suit]]s are not needed.
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| B (11)
 
| B (11)
 
| ([[Corrosive Atmosphere|Corrosive]])   
 
| ([[Corrosive Atmosphere|Corrosive]])   
−
| [[Exotic Atmosphere|Exotic]], Conventional   
+
| [[Exotic Atmosphere|Exotic]] , Conventional   
 
| varies
 
| varies
 
| A concentrated gas mix or unusual temperature creates a corrosive environment, which requires the use of a [[Hostile environment suit]] or [[vacc suit]].
 
| A concentrated gas mix or unusual temperature creates a corrosive environment, which requires the use of a [[Hostile environment suit]] or [[vacc suit]].
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| ([[Dense Atmosphere|Dense]], [[High Pressure Atmosphere|high]])
 
| ([[Dense Atmosphere|Dense]], [[High Pressure Atmosphere|high]])
 
| [[Exotic Atmosphere|Exotic]], Unusual  
 
| [[Exotic Atmosphere|Exotic]], Unusual  
−
| 2.5 or greater {{Page cite|name= Mongoose Traveller Main Rulebook|page=170}}
+
| 2.5 {{Page cite|name= Mongoose Traveller Main Rulebook|page=170}}
−
| Typically no survival gear required under many conditions. Pressure at or below sea level is too great to support life but is breathable at higher altitudes.
+
| Pressure at or below sea level is too great to support life but is breathable at higher altitudes.
 
|-
 
|-
 
| E (14) '''<sup>†</sup>'''
 
| E (14) '''<sup>†</sup>'''
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| [[Exotic Atmosphere|Exotic]], Unusual  
 
| [[Exotic Atmosphere|Exotic]], Unusual  
 
| 0.5 or less {{Page cite|name= Mongoose Traveller Main Rulebook|page=170}}
 
| 0.5 or less {{Page cite|name= Mongoose Traveller Main Rulebook|page=170}}
−
| Typically no survival gear required under many conditions. The world’s surface is [[Ellipsoid World|ellipsoidal]], not spherical. Because the atmosphere remains spherical, surface atmospheric pressure ranges from very high at the middle to very low at the ends. Breathable bands may exist at some point within the range of pressure.
+
| The world’s surface is [[Ellipsoid World|ellipsoidal]], not spherical. Because the atmosphere remains spherical, surface atmospheric pressure ranges from very high at the middle to very low at the ends. Breathable bands may exist at some point within the range of pressure.
 
|-
 
|-
 
| F (15) '''<sup>†</sup>'''
 
| F (15) '''<sup>†</sup>'''
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| [[Exotic Atmosphere|Exotic]], Unusual   
 
| [[Exotic Atmosphere|Exotic]], Unusual   
 
| varies
 
| varies
−
| Typically no survival gear required under some conditions. The [[Ellipsoid World]] is large and massive, with a thin atmosphere which settles to the lowest levels of the terrain. The atmosphere is unbreathable at most altitudes except the very low ones (as in depressions or deep valleys).
+
| The [[Ellipsoid World]] is large and massive, with a thin atmosphere which settles to the lowest levels of the terrain. The atmosphere is unbreathable at most altitudes except the very low ones (as in depressions or deep valleys).
 
|}
 
|}
−
'''<sup>†</sup>''' - '''''NOTE''''':  In '''MgT''' and '''T5''', Atm type '''E''' is "'''Thin, Low'''", and Atm type '''F''' is "'''Unusual'''", which includes (but is not limited to) Ellipsoidal atmospheres.''
+
'''<sup>†</sup>''' - '''''NOTE''':  In '''MgT''' and '''T5''', Atm type '''E''' is "'''Thin, Low'''", and Atm type '''F''' is "'''Unusual'''", which includes (but is not limited to) Ellipsoidal atmospheres.''
  
 
=== Protective Measures Based on Atmosphere ===
 
=== Protective Measures Based on Atmosphere ===
−
The various atmosphere types require specific personal equipment for survival and protection. {{Page cite|name=Worlds and Adventures|page=9|citeName=WA9}}
+
The various atmosphere types require specific personal equipment for survival and protection. {{Page cite|name=Worlds and Adventures|page=9}}
 
* '''Codes 0 and 1:''' [[Vacuum|No atmosphere]] and [[trace atmosphere]] require use of a [[vacc suit]] and associated support equipment.
 
* '''Codes 0 and 1:''' [[Vacuum|No atmosphere]] and [[trace atmosphere]] require use of a [[vacc suit]] and associated support equipment.
 
* '''Codes 2, 4, 7, and 9:''' [[Tainted atmosphere]]s require the use of specialized [[filter mask]]s.
 
* '''Codes 2, 4, 7, and 9:''' [[Tainted atmosphere]]s require the use of specialized [[filter mask]]s.
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* '''Code C:''' [[Insidious atmosphere]]s are similar to [[corrosive atmosphere]]s, but will defeat any personal protective measures in 2 to 12 hours.
 
* '''Code C:''' [[Insidious atmosphere]]s are similar to [[corrosive atmosphere]]s, but will defeat any personal protective measures in 2 to 12 hours.
 
* '''Codes D, E, and F:''' represent "Unusual Atmospheres" with special conditions such as [[Ellipsoid Atmosphere]]s.
 
* '''Codes D, E, and F:''' represent "Unusual Atmospheres" with special conditions such as [[Ellipsoid Atmosphere]]s.
 +
 +
=== Basic Atmosphere Types ===
 +
Combinations of the below atmospheres may exist and are not comprehensively listed:
 +
# [[Corrosive Atmosphere]]
 +
# [[Dense Atmosphere]]
 +
# [[Ellipsoid Atmosphere]]
 +
# [[Exotic Atmosphere]]
 +
# [[High Pressure Atmosphere]]
 +
# [[High Temperature Atmosphere]]
 +
# [[Insidious Atmosphere]]
 +
# [[Low Pressure Atmosphere]]
 +
# [[Low Temperature Atmosphere]]
 +
# [[Standard Atmosphere]] (Tolerable pressure, temperature, constituent gases, etc. for [[Conventional Life|conventional]] [[lifeform]]s)
 +
# [[Tainted Atmosphere]]
 +
# [[Thin Atmosphere]]
 +
# [[Trace Atmosphere]]
 +
# [[Unusual Atmosphere]]
 +
# [[Vacuum]] ([[Interstellar Medium]])
 +
# [[Very Thin Atmosphere]]
 +
 +
=== UWP & Atmospheres ===
 +
The third digit in the UWP identifies the type of atmosphere that the world has. As a rule, only larger worlds have a gravitational field large enough to hold on to an atmosphere, but there certainly are exceptions. An atmosphere is essentially a layer of gas or gasses that cloak the surface of the planet and there are a number of reasons why a world may or may not be lucky enough to have one. As we have already mentioned, a big world has the muscle to keep its atmosphere and the bigger the world, in all likelihood the denser (or thicker) the atmosphere will be. Conversely, moons and small planets with relatively low surface gravities will generally have only trace atmospheres, if they have anything at all. {{Page cite|name=The Universal World Profile|page=13}}
 +
 +
Other factors also come into play. A world sitting close to the main star might have its atmosphere stripped away by the destructive energy of the star's solar wind sweeping past. The only chance a planet has of retaining its layer of gasses in this situation, is if it also benefits from a molten core that is producing a protective magnetosphere. Compare the Earth, whose atmosphere is shielded by its magnetosphere, with Mars. The red planet has a trace or very thin atmosphere that was considerably thicker in ancient times, but as the planet cooled it first lost its magnetosphere and then its atmosphere. {{Page cite|name=The Universal World Profile|page=13}}
 +
 +
Yet there are exceptions; in the depths of the solar system, the moon Titan orbits the ringed planet Saturn. Titan is cold, far from the sun and seismically inactive. It has no magnetosphere and with a surface gravity of only 0.14 G should not be able to retain an atmosphere - yet it has a dense atmosphere that is 1.45 times thicker than that of Earth's! Ganymede and Callisto, comparable-sized moons of Jupiter, are of a similar composition but do not have atmospheres. One theory suggests that Titan, being farther from the sun than the moons of Jupiter, was colder during its formation. Gasses were trapped in the ice at those low temperatures and later made their way into Titan's atmosphere. {{Page cite|name=The Universal World Profile|page=13-14}}
  
 
== History & Background / Dossier ==
 
== History & Background / Dossier ==
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=== Techno-Environmental Limits ===
 
=== Techno-Environmental Limits ===
−
No information yet available.
+
The typical [[sophont]] species needs to invent various kinds of protective equipment in order to colonize atmospheres to which it is not native.
  
 +
:{| class="wikitable sortable" width="90%"
 +
|+ Techno-Environmental Limits
 +
! Atmosphere <br> (Nomenclature)Code
 +
! Minimum <br> [[TL]]
 +
! Remarks
 +
|-
 +
| [[Thin Atmopshere|5]], [[Standard Atmopshere|6]] or [[Dense Atmopshere|8]]
 +
| [[TL-0]]
 +
| No survival equipment required.
 +
|-
 +
| [[Tainted Atmosphere|4, 7 or 9]]         
 +
| [[TL-3]]
 +
| Tainted atmospheres require [[filter]]s.
 +
|-
 +
| [[Very Thin Atmopshere|2 or 3]]
 +
| [[TL-5]]
 +
| Very thin atmospheres require [[compressor]]s.
 +
|-
 +
| [[High Pressure Atmopshere|13 (D)]] or [[Low Pressure Atmopshere14 (E)]]   
 +
| [[TL-5]]
 +
| Unusual atmospheres require a variety of protective equipment.
 +
|-
 +
| [[Vacuum|0]] or [[Trace Atmosphere|1]]         
 +
| [[TL-8]]
 +
| Trace or vacuum atmospheres require a [[vacc suit]] and [[oxygen tank]]s.
 +
|-
 +
| [[Exotic Atmosphere|10 (A)]]           
 +
| [[TL-8]]
 +
| Unbreathable atmospheres require [[oxygen tank]]s.
 +
|-
 +
| [[Unusual Atmosphere|15 (F)]]           
 +
| [[TL-8]]
 +
| Unusual atmospheres such as ellipsoids require equipment under selected conditions.
 +
|-
 +
| [[Corrosive Atmosphere|11 (B)]]           
 +
| [[TL-9]]
 +
| Corrosive atmospheres require a variety of capable protective equipment.
 +
|-
 +
| [[Insidious Atmosphere |12 (C)]]         
 +
| [[TL-10]]
 +
| Insidious atmospheres require a variety of heavy-duty protective equipment.
 +
|-
 +
|}
 +
 
=== Atmospheric Equipment ===
 
=== Atmospheric Equipment ===
 
Some selected [[equipment]] used in nonstandard [[environment]]s with [[Exotic Atmosphere|nonstandard and unusual atmosphere]]s include:
 
Some selected [[equipment]] used in nonstandard [[environment]]s with [[Exotic Atmosphere|nonstandard and unusual atmosphere]]s include:
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# [[Atmospheric Survival Suit]]
 
# [[Atmospheric Survival Suit]]
 
# [[Rescue Ball|Ball, Rescue]]
 
# [[Rescue Ball|Ball, Rescue]]
−
# [[Advanced Base|Base, Advanced]] {{Page cite|name=Worlds and Adventures|page=17|citeName=WA17}}
+
# [[Advanced Base|Base, Advanced]] {{Page cite|name=Worlds and Adventures|page=17}}
 
# [[Battle Dress]]
 
# [[Battle Dress]]
 
# [[Emergency Beacon|Beacon, Emergency]]
 
# [[Emergency Beacon|Beacon, Emergency]]
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# [[Prefabricated Cabin|Cabin, Prefabricated]]
 
# [[Prefabricated Cabin|Cabin, Prefabricated]]
 
# [[Combat Environment Suit]]
 
# [[Combat Environment Suit]]
−
# [[Combination Filter Mask-Respirator]] {{Page cite|citeName=WA17}}
+
# [[Combination Filter Mask-Respirator]] {{Page cite|name=Worlds and Adventures|page=17}}
 
# [[Compressor]]
 
# [[Compressor]]
 
# [[Extended Life Support Sytem]] {{Page cite|name=High Passage 3|page=28}}
 
# [[Extended Life Support Sytem]] {{Page cite|name=High Passage 3|page=28}}
−
# [[Filter Mask]] {{Page cite|citeName=WA17}}
+
# [[Filter Mask]] {{Page cite|name=Worlds and Adventures|page=17}}
 
# [[Filter Respirator Combination]]
 
# [[Filter Respirator Combination]]
 
# [[Filter Suit]]
 
# [[Filter Suit]]
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# [[Protective Mask|Mask, Protective]]
 
# [[Protective Mask|Mask, Protective]]
 
# [[Oxygen Rebreather]]
 
# [[Oxygen Rebreather]]
−
# [[Oxygen Tank]]s {{Page cite|citeName=WA17}}
+
# [[Oxygen Tank]]s {{Page cite|name=Worlds and Adventures|page=17}}
−
# [[Pre-Fabricated Cabin]] {{Page cite|citeName=WA17}}
+
# [[Pre-Fabricated Cabin]] {{Page cite|name=Worlds and Adventures|page=17}}
−
# [[Respirator]] {{Page cite|citeName=WA17}}
+
# [[Respirator]] {{Page cite|name=Worlds and Adventures|page=17}}
 
# [[Regulator]]
 
# [[Regulator]]
 
# [["Sniffer" Bioscanner]]
 
# [["Sniffer" Bioscanner]]
 
# [[Suit Air Conditioner]]
 
# [[Suit Air Conditioner]]
−
# [[Protective Suit|Suit, Protective]] {{Page cite|citeName=WA17}}
+
# [[Protective Suit|Suit, Protective]] {{Page cite|name=Worlds and Adventures|page=17}}
 
# [[Heavy Protective Suit|Suit, Protective, Heavy]]
 
# [[Heavy Protective Suit|Suit, Protective, Heavy]]
 
# [[Survival Bubble]]
 
# [[Survival Bubble]]
−
# [[Pressure Tent|Tent, Pressure]] {{Page cite|citeName=WA17}}
+
# [[Pressure Tent|Tent, Pressure]] {{Page cite|name=Worlds and Adventures|page=17}}
−
# [[Vacc Suit]] {{Page cite|citeName=WA17}} {{Page cite|name= Twilight's Peak|page=5}}
+
# [[Vacc Suit]] {{Page cite|name=Worlds and Adventures|page=17}} {{Page cite|name= Twilight's Peak|page=5}}
  
 
== References and Contributors ==
 
== References and Contributors ==
Line 212: Line 248:
 
|S1= {{Ludography cite|name=Worlds and Adventures|page=5}}
 
|S1= {{Ludography cite|name=Worlds and Adventures|page=5}}
 
|S2= {{Ludography cite|name=Exotic Atmospheres|page=1-16}} (Special Supplement 2 from the periodical [[Journal of the Travellers' Aid Society 17]])
 
|S2= {{Ludography cite|name=Exotic Atmospheres|page=1-16}} (Special Supplement 2 from the periodical [[Journal of the Travellers' Aid Society 17]])
−
|S3= [[Grand Survey]]
+
|S3= {{Ludography cite|name=Referee's Manual|page=22}}
−
|S4= {{Ludography cite|name=Referee's Manual|page=22}}
+
|S4= {{Ludography cite|name=World Builder's Handbook|page=64-68}}
−
|S5= {{Ludography cite|name=World Builder's Handbook|page=64-68}}
+
|S5= {{Ludography cite|name=World Tamer's Handbook|page=11-17}}
−
|S6= {{Ludography cite|name=World Tamer's Handbook|page=11-17}}
+
|S6= {{Ludography cite|name=First In|page=70,72}}
−
|S7= {{Ludography cite|name=First In|page=69-70,72}}
+
|S7= {{Ludography cite|name=Interstellar Wars|page=125-6}}  
−
|S8= {{Ludography cite|name=Interstellar Wars|page=125-6}}  
+
|S8= {{Ludography cite|name=Mongoose Traveller Main Rulebook|page=TBD}}
−
|S9= {{Ludography cite|name=Mongoose Traveller Main Rulebook|page=TBD}}
+
|S9= {{Ludography cite|name=T5 Core Rules|page=409}}
−
|S10= {{Ludography cite|name=T5 Core Rules|page=409}}
+
|S10= {{Ludography cite|name=The Universal World Profile|page=TBD}}
−
|S11= {{Ludography cite|name=The Universal World Profile|page=TBD}}
+
|S11= Author & Contributor: Lord (Marquis) and Master of Sophontology [[User:Maksim-Smelchak|Maksim-Smelchak]] of the [[Ministry of Science]]
−
|S12= [[Traveller Wiki Editorial Team]]
 
−
|S13= Author & Contributor: Lord (Marquis) and Master Scout Emeritus [[User: Alagoric|Adie Alegoric Stewart]] of the [[IISS]]
 
−
|S14= Author & Contributor: Jonathan Sherlock
 
−
|S15= Author & Contributor: Lord (Marquis) and Master of Sophontology [[User:Maksim-Smelchak|Maksim-Smelchak]] of the [[Ministry of Science]]
 
 
}}
 
}}
 
   
 
   
  
 
{{LE|Planetology|Planets}}
 
{{LE|Planetology|Planets}}

Revision as of 00:14, 2 May 2018

The Atmosphere Code is a UWP code to represent the breathing environment encountered on a world.

  • It represents the mixture of gases and other elements that may be present on a sufficiently sized world or moon.
  • Varying types of atmospheres require the use of protective clothing or masks. [1]
  • Very small worlds, planetoids, asteroids, and other small objects almost never have an atmosphere unless artificially modified using advanced technology.
  • Tent Worlds are an example of a world ordinarily too small to contain an atmosphere, but artificially and technologically modified to possess an atmosphere using paraterraforming.

Description / Specifications

Few worlds will be found where a single chemical makes up the entire atmosphere. Most atmospheres have a complex gas mix which will include a variety of specific elements, some in great amounts, while others are barely detectable. Atmospheric mixes include active and inert gases. On Earth, oxygen (02) is active, but forms less than 25% of the total atmosphere around us. Three times as much is nitrogen (N2), plus a few trace elements such as argon. These inert gases are not usually required by animal at plant life, and take no part in the chemical reactions essential for life (except for nitrogen, a special case). They are, nonetheless, part of the atmosphere. In this AAB article, when we refer to a specific gas such as methane making up an atmosphere, we are referring to the active element, which may make up only a fraction of the total atmospheric mix. [2]

World Atmosphere Classification Codes Table

As a generality, small worlds are unable to maintain a sufficient gravity to maintain an atmosphere and tend to have thinner or trace atmospheres while larger worlds grow increasingly dense. Corrosive and insidious worlds tend to be at extreme ends of the tolerable temperature spectrum.

Atmospheric Code Descriptions
Code Specific Description General Description Pressure (ATM) Remarks
0 Vacuum Vacuum < 0.001 Vacuum requires a vacc suit. The atmosphere has a pressure of less than 0.001 atmospheres, which requires the use of a vacc suit.
1 (Trace) Vacuum 0.001-0.09 The atmosphere has a pressure of less than 0.1 atmospheres, which requires the use of a vacc suit.
2 (Very Thin / Tainted) Vacuum 0.10-0.42 Very Thin tainted requires a filter respirator combination
3 (Very Thin) Vacuum 0.10-0.42 Very Thin requires a respirator. The atmosphere has a pressure of 0.1 to 0.42 atmospheres, which requires the use of a respirator to ensure sufficient oxygen.
4 (Thin / Tainted) Thin 0.43-0.70 Tainted requires a filter mask. The atmosphere contains an unusual taint such as such as disease, a hazardous gas mix, pollutants, or sulfur compounds which requires the use of a filter mask.
5 Thin Thin 0.43-0.70 The atmosphere has a pressure of 0 43 to 0.70 atmospheres. The atmosphere is a standard oxygen/nitrogen mix, which is breathable without assistance.
6 Standard Standard 0.71-1.49 The atmosphere has a pressure of 0.71 to 1.49 atmospheres. The atmosphere is a standard oxygen/nitrogen mix, which is breathable without assistance.
7 (Standard / Tainted) Standard 0.71-1.49 Tainted requires a filter mask.
8 Dense Dense 1.50-2.49 The atmosphere has a pressure of 1.50 to 2.49 atmospheres The atmosphere is a standard oxygen/nitrogen mix, which is breathable without assistance.
9 (Dense / Tainted) Dense 1.50-2.49 Tainted requires a filter mask.
A (10) Exotic Exotic , Conventional varies An unusual gas mix which requires the use of oxygen tanks, but protective suits are not needed.
B (11) (Corrosive) Exotic , Conventional varies A concentrated gas mix or unusual temperature creates a corrosive environment, which requires the use of a Hostile environment suit or vacc suit.
C (12) (Insidious) Exotic, Conventional varies The atmosphere is similar to a corrosive atmosphere, but extreme conditions cause the corrosive effects to defeat any protective measures in 2 to 12 hours.
D (13) (Dense, high) Exotic, Unusual 2.5 [3] Pressure at or below sea level is too great to support life but is breathable at higher altitudes.
E (14) † (Ellipsoid) † Exotic, Unusual 0.5 or less [4] The world’s surface is ellipsoidal, not spherical. Because the atmosphere remains spherical, surface atmospheric pressure ranges from very high at the middle to very low at the ends. Breathable bands may exist at some point within the range of pressure.
F (15) † (Thin, low) † Exotic, Unusual varies The Ellipsoid World is large and massive, with a thin atmosphere which settles to the lowest levels of the terrain. The atmosphere is unbreathable at most altitudes except the very low ones (as in depressions or deep valleys).

† - NOTE: In MgT and T5, Atm type E is "Thin, Low", and Atm type F is "Unusual", which includes (but is not limited to) Ellipsoidal atmospheres.

Protective Measures Based on Atmosphere

The various atmosphere types require specific personal equipment for survival and protection. [5]

Basic Atmosphere Types

Combinations of the below atmospheres may exist and are not comprehensively listed:

  1. Corrosive Atmosphere
  2. Dense Atmosphere
  3. Ellipsoid Atmosphere
  4. Exotic Atmosphere
  5. High Pressure Atmosphere
  6. High Temperature Atmosphere
  7. Insidious Atmosphere
  8. Low Pressure Atmosphere
  9. Low Temperature Atmosphere
  10. Standard Atmosphere (Tolerable pressure, temperature, constituent gases, etc. for conventional lifeforms)
  11. Tainted Atmosphere
  12. Thin Atmosphere
  13. Trace Atmosphere
  14. Unusual Atmosphere
  15. Vacuum (Interstellar Medium)
  16. Very Thin Atmosphere

UWP & Atmospheres

The third digit in the UWP identifies the type of atmosphere that the world has. As a rule, only larger worlds have a gravitational field large enough to hold on to an atmosphere, but there certainly are exceptions. An atmosphere is essentially a layer of gas or gasses that cloak the surface of the planet and there are a number of reasons why a world may or may not be lucky enough to have one. As we have already mentioned, a big world has the muscle to keep its atmosphere and the bigger the world, in all likelihood the denser (or thicker) the atmosphere will be. Conversely, moons and small planets with relatively low surface gravities will generally have only trace atmospheres, if they have anything at all. [6]

Other factors also come into play. A world sitting close to the main star might have its atmosphere stripped away by the destructive energy of the star's solar wind sweeping past. The only chance a planet has of retaining its layer of gasses in this situation, is if it also benefits from a molten core that is producing a protective magnetosphere. Compare the Earth, whose atmosphere is shielded by its magnetosphere, with Mars. The red planet has a trace or very thin atmosphere that was considerably thicker in ancient times, but as the planet cooled it first lost its magnetosphere and then its atmosphere. [7]

Yet there are exceptions; in the depths of the solar system, the moon Titan orbits the ringed planet Saturn. Titan is cold, far from the sun and seismically inactive. It has no magnetosphere and with a surface gravity of only 0.14 G should not be able to retain an atmosphere - yet it has a dense atmosphere that is 1.45 times thicker than that of Earth's! Ganymede and Callisto, comparable-sized moons of Jupiter, are of a similar composition but do not have atmospheres. One theory suggests that Titan, being farther from the sun than the moons of Jupiter, was colder during its formation. Gasses were trapped in the ice at those low temperatures and later made their way into Titan's atmosphere. [8]

History & Background / Dossier

All industrial societies must gain an expanded understanding of atmospheres, air pressure, atmospheric constituents, gas behavior, industrial pollutants, and other factors in order to build a successful, modern interstellar starfaring society of TL:10-12 or greater. The UWP is one of the external expressions of those expectations about atmospheric understandings within Charted Space.

Techno-Environmental Limits

The typical sophont species needs to invent various kinds of protective equipment in order to colonize atmospheres to which it is not native.

Techno-Environmental Limits
Atmosphere
(Nomenclature)Code 		Minimum
TL 		Remarks
5, 6 or 8 TL-0 No survival equipment required.
4, 7 or 9 TL-3 Tainted atmospheres require filters.
2 or 3 TL-5 Very thin atmospheres require compressors.
13 (D) or Low Pressure Atmopshere14 (E) TL-5 Unusual atmospheres require a variety of protective equipment.
0 or 1 TL-8 Trace or vacuum atmospheres require a vacc suit and oxygen tanks.
10 (A) TL-8 Unbreathable atmospheres require oxygen tanks.
15 (F) TL-8 Unusual atmospheres such as ellipsoids require equipment under selected conditions.
11 (B) TL-9 Corrosive atmospheres require a variety of capable protective equipment.
12 (C) TL-10 Insidious atmospheres require a variety of heavy-duty protective equipment.

Atmospheric Equipment

Some selected equipment used in nonstandard environments with nonstandard and unusual atmospheres include:

  1. Air Tanks
  2. Atmosphere Tester
  3. Atmospheric Survival Suit
  4. Ball, Rescue
  5. Base, Advanced [9]
  6. Battle Dress
  7. Beacon, Emergency
  8. Body Pressure Suit
  9. Cabin, Prefabricated
  10. Combat Environment Suit
  11. Combination Filter Mask-Respirator [10]
  12. Compressor
  13. Extended Life Support Sytem [11]
  14. Filter Mask [12]
  15. Filter Respirator Combination
  16. Filter Suit
  17. Gauge, Depth
  18. Gauge, Tank Pressure
  19. Hazard Suit
  20. Hostile Environment Suit
  21. Locator, Inertial
  22. Mask, Face
  23. Mask, Filter
  24. Mask, Protective
  25. Oxygen Rebreather
  26. Oxygen Tanks [13]
  27. Pre-Fabricated Cabin [14]
  28. Respirator [15]
  29. Regulator
  30. "Sniffer" Bioscanner
  31. Suit Air Conditioner
  32. Suit, Protective [16]
  33. Suit, Protective, Heavy
  34. Survival Bubble
  35. Tent, Pressure [17]
  36. Vacc Suit [18] [19]

References and Contributors

This list of sources was used by the Traveller Wiki Editorial Team and individual contributors to compose this article. Copyrighted material is used under license from Far Future Enterprises or by permission of the author. The page history lists all of the contributions.
  1. ↑ Marc Miller. Worlds and Adventures (Game Designers Workshop, 1977), 7.Marc Miller, Robert Eaglestone, Don McKinney. Worlds and Adventures (Far Future Enterprises, 2019), 7.
  2. ↑ J. Andrew Keith. Exotic Atmospheres (Game Designers Workshop, 1983), 3-4.
  3. ↑ Citation Missing - Mongoose Traveller Main Rulebook
  4. ↑ Citation Missing - Mongoose Traveller Main Rulebook
  5. ↑ Marc Miller. Worlds and Adventures (Game Designers Workshop, 1977), 9.Marc Miller, Robert Eaglestone, Don McKinney. Worlds and Adventures (Far Future Enterprises, 2019), 9.
  6. ↑ Paul Elliott. The Universal World Profile (Zozer Games, 2016), 13.
  7. ↑ Paul Elliott. The Universal World Profile (Zozer Games, 2016), 13.
  8. ↑ Paul Elliott. The Universal World Profile (Zozer Games, 2016), 13-14.
  9. ↑ Marc Miller. Worlds and Adventures (Game Designers Workshop, 1977), 17.Marc Miller, Robert Eaglestone, Don McKinney. Worlds and Adventures (Far Future Enterprises, 2019), 17.
  10. ↑ Marc Miller. Worlds and Adventures (Game Designers Workshop, 1977), 17.Marc Miller, Robert Eaglestone, Don McKinney. Worlds and Adventures (Far Future Enterprises, 2019), 17.
  11. ↑ Jim Cunningham. High Passage 3 (FASA, 1982), 28.
  12. ↑ Marc Miller. Worlds and Adventures (Game Designers Workshop, 1977), 17.Marc Miller, Robert Eaglestone, Don McKinney. Worlds and Adventures (Far Future Enterprises, 2019), 17.
  13. ↑ Marc Miller. Worlds and Adventures (Game Designers Workshop, 1977), 17.Marc Miller, Robert Eaglestone, Don McKinney. Worlds and Adventures (Far Future Enterprises, 2019), 17.
  14. ↑ Marc Miller. Worlds and Adventures (Game Designers Workshop, 1977), 17.Marc Miller, Robert Eaglestone, Don McKinney. Worlds and Adventures (Far Future Enterprises, 2019), 17.
  15. ↑ Marc Miller. Worlds and Adventures (Game Designers Workshop, 1977), 17.Marc Miller, Robert Eaglestone, Don McKinney. Worlds and Adventures (Far Future Enterprises, 2019), 17.
  16. ↑ Marc Miller. Worlds and Adventures (Game Designers Workshop, 1977), 17.Marc Miller, Robert Eaglestone, Don McKinney. Worlds and Adventures (Far Future Enterprises, 2019), 17.
  17. ↑ Marc Miller. Worlds and Adventures (Game Designers Workshop, 1977), 17.Marc Miller, Robert Eaglestone, Don McKinney. Worlds and Adventures (Far Future Enterprises, 2019), 17.
  18. ↑ Marc Miller. Worlds and Adventures (Game Designers Workshop, 1977), 17.Marc Miller, Robert Eaglestone, Don McKinney. Worlds and Adventures (Far Future Enterprises, 2019), 17.
  19. ↑ Marc Miller. Twilight's Peak (Game Designers Workshop, 1980), 5.
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