Planet's Water Question

[casquilho]

I had an idea and realized I am unsure of an answer. If a planet has Hydrographic %, does it have to be surface water or could it be below the surface of the planet? Could a planet look like a desert world but have water below the surface that could be pumped up to the surface? Or does the Hydrographic % mean the % of surface covered by water?

I am sure I should know this but I am drawing a blank and can't find the answer.

Thank You for your help.

 

[Spinward Flow]

does the Hydrographic % mean the % of surface covered by water?

While there are exceptions (Ice Capped, Fluid Oceans, etc.), in the main hydrographic percentage is meant to represent the proportion of surface that is liquid. Usually this means water ocean(s), but not always.

Terra, for example is ~69% water on the surface, so Terra has a hydrographic code of 7.

 

[casquilho]

While there are exceptions (Ice Capped, Fluid Oceans, etc.), in the main hydrographic percentage is meant to represent the proportion of surface that is liquid. Usually this means water ocean(s), but not always.

Terra, for example is ~69% water on the surface, so Terra has a hydrographic code of 7.

Thank You Sir. I thought that was the case, but could not find it for sure.

 

[McPerth]

If a planet has Hydrographic %, does it have to be surface water or could it be below the surface of the planet?

Several sources specify it's surface water (or other fluids, in exotic atmospheres), be it in solid or liquid form. A world with hydrographycs 0 can still have large amounts of subsurface water.

 

[G. Kashkanun Anderson]

Could a planet look like a desert world but have water below the surface that could be pumped up to the surface?

A lot of these worlds -- and by that I mean the Dune and Tatooine type worlds, not airless rocks -- would be very, very old planets whose surface water has since been subducted into the lower crust or mantle by now dormant (or at least very soon to be dormant) tectonic activity. Most of these worlds would not have liquid aquifers in the way that we understand them, however; instead, water would have to be accessed in the form of churning up hydrous minerals via deep mining activity and unlocking them in refineries, assuming the local tech level and economic realities make that a feasible option.

I can think of at least one world in OTU canon that is at this moment relatively late in the process of transforming from Terra-like to Dune-like: Jaeyelya, the semi-desiccated homeworld of the Ael Yael. The mineral rich 'Glittering Floor' geographic feature of that world is the basin of a dying ocean.

While there are exceptions (Ice Capped, Fluid Oceans, etc.), in the main hydrographic percentage is meant to represent the proportion of surface that is liquid. Usually this means water ocean(s), but not always.

This allows me to vent on something that has always bothered me about one of the Trade Codes: namely, type A atmospheres do not mean fluid oceans!

Or, at least, most of them wouldn't. Type A atmosphere worlds are unbreathable (reducing/no oxygen) but otherwise shirtsleeve/light protection environments. This means -- or at least very strongly suggests -- that no exotic chemicals are dominant.* The bog standard of such an arrangement would be a mixture of carbon dioxide, nitrogen, water vapor and traces of other elements, AKA the same general atmosphere that Terra had for most of the first 2 billion years or so of its existence.

And we had oceans chock full of water during all that time. Gnarly, possibly smelly, anaerobic water, for the most part. But it was still water.

*It also means that they are in the Habitable Zone -- or at least whatever range that would be for them, given the albedo and greenhouse qualities of their particular atmosphere mix, since 'protective suits are not needed' also means not requiring any special protection against dying horribly of ultra-frostbite or being cooked to death.

 

[Condottiere]

Dirt covered iceball.

Frozen centre, instead of a molten core.

 

[Spinward Flow]

This allows me to vent on something that has always bothered me about one of the Trade Codes: namely, type A atmospheres do not mean fluid oceans!

Or, at least, most of them wouldn't. Type A atmosphere worlds are unbreathable (reducing/no oxygen) but otherwise shirtsleeve/light protection environments. This means -- or at least very strongly suggests -- that no exotic chemicals are dominant.* The bog standard of such an arrangement would be a mixture of carbon dioxide, nitrogen, water vapor and traces of other elements, AKA the same general atmosphere that Terra had for most of the first 2 billion years or so of its existence.

And we had oceans chock full of water during all that time. Gnarly, possibly smelly, anaerobic water, for the most part. But it was still water.

For UWP purposes, what you're describing amounts to a Tainted atmosphere (pressure not relevant to the purposes of our discussion).

However, a location such as Titan ought to be considered Atmosphere: A with an above zero hydrographics, yielding Fluid Oceans (or lakes, if hydrographics are low enough). The reason why Titan is not merely Atmosphere: 9 (Dense, Tainted) is because of the chemistry involved (solid, liquid and gaseous). The atmosphere is low (to no) oxygen content, so you can't just use a filter to breathe it (which you can do with tainted atmospheres in Traveller). The temperature is so low that water is not liquid, it is solid (like rock) on Titan. The atmosphere and liquid on the surface are loaded with hydrocarbons thanks to photochemistry due to sunlight.

So Titan's atmosphere is "hostile" ... but not actively so like the atmosphere of Venus (which is loaded with sulfuric acid).
With enough thermal insulation/protection (because Titan is COLD!), it would be possible to walk around in Titan's atmosphere without a pressure suit ... but you would still need to bring your own oxygen to breathe (because the atmosphere won't have useful enough quantities to work with).

 

[Krikkitone]

For UWP purposes, what you're describing amounts to a Tainted atmosphere (pressure not relevant to the purposes of our discussion).

However, a location such as Titan ought to be considered Atmosphere: A with an above zero hydrographics, yielding Fluid Oceans (or lakes, if hydrographics are low enough). The reason why Titan is not merely Atmosphere: 9 (Dense, Tainted) is because of the chemistry involved (solid, liquid and gaseous). The atmosphere is low (to no) oxygen content, so you can't just use a filter to breathe it (which you can do with tainted atmospheres in Traveller). The temperature is so low that water is not liquid, it is solid (like rock) on Titan. The atmosphere and liquid on the surface are loaded with hydrocarbons thanks to photochemistry due to sunlight.

So Titan's atmosphere is "hostile" ... but not actively so like the atmosphere of Venus (which is loaded with sulfuric acid).
With enough thermal insulation/protection (because Titan is COLD!), it would be possible to walk around in Titan's atmosphere without a pressure suit ... but you would still need to bring your own oxygen to breathe (because the atmosphere won't have useful enough quantities to work with).

No he’s describing type A…a Nitrogen atmosphere with no oxygen
Titan is Also type A.

So one could say that water oceans are possible on type A…of course they are also possible on type B and probably C as well.

If Venus cooled off the sulfuric acid…well that’s water…just with sulfuric acid in it.

I think the “Fluid” code means significant liquid with more than just a little taint.
If you removed all the oxygen and photosynthesizers from Earth, the oceans would very quickly* have a bunch of nasty/useful compounds, even though they are 99.99% water.

*ecologic and or geological time

 

[Spinward Flow]

If Venus cooled off the sulfuric acid…well that’s water…just with sulfuric acid in it.

Old chemistry joke.
Do not confuse the H₂O with H₂SO₄.

If you need to "do your own research" on why the joke is funny ... well ... it's your funeral.

 

[mike wightman]

Two chemists walk into a bar.
"what will it be gents?" asks the barkeep
"I'll have eitch two ohh!" says the first, pretentiously.
The second, not to be outdone, says:
"I'll have eitch two ohh too". He takes a sip and his head explodes.

 

[Grav_Moped]

Old chemistry joke.
Do not confuse the H₂O with H₂SO₄.

If you need to "do your own research" on why the joke is funny ... well ... it's your funeral.

Set-up for the punchline: "I can't quite recall -- it's on the tip of my tongue."

 

[G. Kashkanun Anderson]

So Titan's atmosphere is "hostile" ... but not actively so like the atmosphere of Venus (which is loaded with sulfuric acid).
With enough thermal insulation/protection (because Titan is COLD!), it would be possible to walk around in Titan's atmosphere without a pressure suit ... but you would still need to bring your own oxygen to breathe (because the atmosphere won't have useful enough quantities to work with).

And what you are describing in this case is explicitly not a Type A atmosphere as it is put forth in the Traveller rules:

"Exotic atmospheres require the use of oxygen tanks, but protective suits are not required."
-- CT LBB 3 ('Worlds & Adventures'), page

This is a description of a simple inert or nontoxic reducing (anaerobic) environment. They are otherwise not hostile environments. You may not be able to breathe in it, but you are able to walk around otherwise unclad -- or at least in as little as local modesty rules and basic hygiene or comfort allow.

The average temperature on Titan, on the other hand, is -180c. There is no amount of exposed human skin that is safe under those conditions.

If you are on a world where you have to wear full protective gear in order to prevent yourself from experiencing a medical emergency upon contact with it, if not outright death, then its environment is more than just 'exotic'; it is 'corrosive' or 'insidious'. There is no reason why these definitions should be limited to a chemical processes, as extreme cold and/or heat (and radiation, for that matter) can be just as destructive to people and equipment as many chemical processes.

I think the “Fluid” code means significant liquid with more than just a little taint.
If you removed all the oxygen and photosynthesizers from Earth, the oceans would very quickly have a bunch of nasty/useful compounds, even though they are 99.99% water.

I've considered that, personally. And I would have been willing to acknowledge that as an official possibility, except for the fact that the rules, again, state otherwise:

"Fluid Oceans: Oceans composed of fluids other than water."
-- CT LBB 7 ('Merchant Prince'), page 36

The authors clearly wanted something other than water for these places, such as worlds with ammonia, methane or even nitrogen or chorine oceans. You know, good 'n weird, high space opera, science fictioney environments. I guess my problem with that is that I can not see any way to have such a thing without making the rest of the world as brutally toxic to human life as those oceans. Worlds with Type B and C atmospheres are easy to conjure up that way (with the varying deadly combinations of extreme pressures, temperatures or nasty chemicals allowing for it), but Type A atmospheres are just too ... accommodating, at least in the galactic sense.

 

[Spinward Flow]

So Titan's atmosphere is "hostile" ... but not actively so like the atmosphere of Venus (which is loaded with sulfuric acid).
With enough thermal insulation/protection (because Titan is COLD!), it would be possible to walk around in Titan's atmosphere without a pressure suit ... but you would still need to bring your own oxygen to breathe (because the atmosphere won't have useful enough quantities to work with).

And what you are describing in this case is explicitly not a Type A atmosphere as it is put forth in the Traveller rules:

"Exotic atmospheres require the use of oxygen tanks, but protective suits are not required."
-- CT LBB 3 ('Worlds & Adventures'), page

This is a description of a simple inert or nontoxic reducing (anaerobic) environment. They are otherwise not hostile environments. You may not be able to breathe in it, but you are able to walk around otherwise unclad -- or at least in as little as local modesty rules and basic hygiene or comfort allow.

The average temperature on Titan, on the other hand, is -180c. There is no amount of exposed human skin that is safe under those conditions.

Hmmm ... let's see. What did I write that obviously wasn't comprehended?

So Titan's atmosphere is "hostile" ... but not actively so like the atmosphere of Venus (which is loaded with sulfuric acid).

Chemically speaking, if you warmed up Titan's atmosphere (to a nominal 15-25º C) through some kind of heat exchanger system, a human wouldn't be able to (usefully) breathe it due to a lack of O₂ in it. Therefore, you would need to bring your own (tanked) oxygen to breathe in Titan's atmosphere.

Exotic atmospheres require the use of oxygen tanks

With enough thermal insulation/protection (because Titan is COLD!), it would be possible to walk around in Titan's atmosphere without a pressure suit

That's a thermal problem, rather than an atmospheric pressure problem. In other words, a full on vacc suit is not necessarily required for a "pressure sealed environment" to keep a human alive.

Additionally, LBB3.81 was written at a time when ALL of the mainworlds represented by UWP codes were in the "habitable zone" and thus biased towards being survivable. The fact that Titan is a moon of an "outer orbit gas giant" located beyond the snow line in the Sol system wasn't a factor when LBB3.81 was being written and edited.

but protective suits are not required

If you step over the thermal issue (because outer system planetary orbit), Titan's atmosphere is not chemically hostile in an active way to machinery, technology and engineering, let alone human flesh. Titan's atmosphere will not chemically "destroy" stuff the same way (or at the same rate) that superheated sulfuric acid suspended in the atmosphere would. The hydrocarbon chemistry of Titan's atmosphere is "relatively benign" (code: A) compared to the sulfuric acid chemistry present in the atmosphere of Venus (code: B).

To take the analogy one step further, I would imagine that an atmosphere which is predominantly chlorine/fluorine would be code: B-C depending on chemical composition and how rapidly that atmospheric chemistry "attacks" machinery, technology and engineering (let alone human flesh).

Titan's atmosphere may "smell bad" and it may leave an unpleasant residue on anything moving around in it, but it isn't going to start DISSOLVING machines and people exposed to it.

The atmosphere of Venus, however ... IT HATES EVERYTHING ... especially down at the planetary surface (where everything gets "hot & melty"). Higher up in the Venusian atmosphere, where the pressure drops down to "Terra nominal" the temperature also drops to something "Terra nominal" but you're still looking at an atmosphere that is actively circulating sulfuric acid through it, so not only will it SMELL like rotten eggs (that distinctive sulfur smell) but it will also slowly EAT whatever is put there (in some kind of "floating city" context).

Sulfuric acid doesn't chemically "attack" everything, necessarily ... but there are an awful lot of materials and molecules that sulfuric acid "doesn't play nice with" ... so code: B Corrosive at the bare minimum.