Hydro Code

[Garnfellow]

Reading that NASA Spots What May Be Plumes Of Water On Jupiter's Moon Europa, I wondered about Traveller's hydro code. In GURPS, the hydro code is specifically defined as liquid surface water, so a world completely covered with frozen water could have a hydro value of 0%.

Do other versions of Traveller also specify liquid water as part of the hydro code? How would T5 code Europa's hydro code?

 

[Magnus von Thornwood]

Ic?

For T5, maybe Ice-capped or in this case Ice-covered..hmm, dangit I packed up the Traveller for the move and so can't check there might be Ice Worlds now that I think of it, by the Other Worlds section with Storm and Big Worlds.

So, myabe Hydro 0, Ice-capped? Or Ice World.

 

[SanDragon]

Having poked through my T5.09, I bid frozen!

Beyond habitable zone by a minimum of +2, and most gases being a solid by then.

 

[Timerover51]

Tho following statements appear in the cited Classic Traveller books.

1981 Edition LBB3: Worlds and Adventures, page 9.

Hydrographics: It is possible for some worlds with vacuum atmospheres to have hydrographic percentages greater than 0. In such cases, the world has ice-caps present; the water will not be free-standing liquid

Traveller Starter Edition Book 1, page 45.

Ice-capped worlds have water present only in the form of ice caps; these are vacuum worlds which would otherwise have no water. An ice-capped world has an atmosphere of 0 or 1 and hydrographic percentage of 1 or greater.

The Traveller Book, page 83.

Hydrographics: It is possible that some worlds with vacuum atmospheres may have hydrographic percentages greater than 0. In such cases, the world has ice-caps present; the water will not be free-standing liquid

T4: Marc Miller's Traveller, page 132.

Hydrographlcs: It is possible that some worlds with vacuum atmospheres may have hydrographic percentages greater than zero. In such cases, the world has ice-caps present, and the water will not be free-standing liquid.

Traveller 5.09 allows for Ice-Capped Worlds, with no liquid water present on the surface.

If using the 1977 Edition of the LBB, where the Hydrographic percentage is 2D-7+Size, you could readily get an ice-capped world if you roll 7 or higher on the die roll, with the atmosphere of 0 or 1.

Europa could exist in Traveller without major problems.

Edit Note: I do not have MegaTraveller on my computer, but will check later tonight. I suspect that it will echo the Classic books.

 

[Timerover51]

Do other versions of Traveller also specify liquid water as part of the hydro code? How would T5 code Europa's hydro code?

T5, per page 410 would code Europa as a Hydrographic code of "A". with atmosphere of "0".

 

[Garnfellow]

T5, per page 410 would code Europa as a Hydrographic code of "A". with atmosphere of "0".

For a UWP of something like X20A000-0.

Interestingly, you could never generate that result through T5. The IceWorld secondary world type probably ought to allow that somehow, but it doesn't. In fact, you currently could end up with an IceWorld with hydro of 0.

I like that T5 has different classes for secondary worlds, but as written they don't produce particularly distinct results.

 

[McPerth]

Edit Note: I do not have MegaTraveller on my computer, but will check later tonight. I suspect that it will echo the Classic books.

Your suspiction is right. MT:RM, page 21:

Hydrosphere: (...) Some worlds with vacuum atmospheres may have hydrographic percentages greater than 0: the world has ice caps present; the water will not be free-standing liquid

See that the Ic (ice caped) travel code is specifically for thsoe cases...

I guess an ice world would in fact be hydrophere A...