Corran J. Webster · 20 November 1992
Hi again,
Well, I seem to have got some response to my posting...
Catie Helm([email removed]) writes:
> Now about Corran's proposed UPP scale, based mostly on planetary
> composition, which translated to rocks, solid cores, molten cores,
> etc.
I actually stole these classifications from the World Builders'
Handbook by DGP, in a vague attempt to fit in with some previously
published information. The World Builders' Handbook basically uses
these to split planets up into density categories:
Icy body = 0.18 to 0.48 earths
Rocky Body = 0.50 to 0.80 earths
Molten Core = 0.82 to 1.12 earths
Heavy Core = 1.10 to 2.25 earths
OK, let's try discarding the idea of whether or not the core is molten
or not, and just stick with categories such as "Icy body", and three
grades of Rocky bodies: "Light", "Medium" and "Heavy". I'm pretty sure
it doesn't matter to the average player whether or not the core is
currently molten. Actually I'll take that back - molten cores and so
forth would probably affect the existence of magnetic fields,
radiation belts, volcanic action (expert opinions welcome :-), so it
probably would affect things. In fact I suppose a "molten core" icy
body could be an icy body with liquid underneath a crust of ice (I
think Europa is thought to be like this?). Nevertheless gravity and
atmosphere are far more fundamental...
One thing I'm unsure about is where a moon like Io fits into the
scheme of things: it's certainly not icy, does it have a rocky core?
what's it's density? Should the "icy body" category contain strange
bodies like Io?
OK, so now we can work out the approximate atmospheric pressure:
assume that icy bodies have a density of 1/3 of that of earth (an
over-estimate?), light rocky bodies have a density of 2/3, medium
rocky bodies have a density of 1 and heavy rocky bodies have a
density of 4/3. Then the formula is:
density*size/8
(which incidentally is also the surface gravity). In terms of the
original traveller atmosphere densities (vacuum: 0 atm, trace: 0 -
0.09 atm, v. thin: 0.10 - 0.42, thin: 0.43 - 0.70, std 0.71 - 1.49,
dense: 1.50 - 2.49) we have:
size
0/S 1 2 3 4 5 6 7 8 9 A
d "icy" vac tr tr vt vt vt vt vt vt vt th
e light vac tr vt vt vt th th th th st st
n medium vac vt vt vt th th st st st st st
s heavy vac vt vt th th st st st st de de
Consequences:
Much fewer worlds with _no_ atmosphere, much more with very thin
atmospheres, fewer worlds with dense atmospheres, and probably fewer
with standard atmospheres. It also gets rid of my original gripe about
small worlds with normal atmospheres.
Problem:
I notice that the Moon (size 2, density light) and mercury (size 3,
density medium) should have very thin atmosphere (Moon: atm pressure
approx 0.16). This seems too high (according to the rules you could
breathe on the moon with the aid of a compressor)... I suspect it is a
problem with the pressure = gravity approximation.
Perhaps larger world sizes should be allowed?
Solution:
Modifiers: If the world is in the inner or habital zones and has a
size of 0,S,1,2,3, then decrease the atm type by one (eg. th -> vt ->
tr -> vac), which solves the problem of Mercury and the Moon.
Any other suggestions, folks?
Right, so then there's only atmospheric composition left, and that can
be summarised into the following categories:
OK to breathe:Standard 02/N2 type mix
Bad news to breathe:Tainted 02/N2 type mix
Really bad news to breathe:Exotic
Wear your protective gear:Irritant, Corrosive, Insidious
Finally there are the weird ones: D (dense, high), E (ellipsoid), F
(thin, low). These are really atmospheric pressure considerations, (in
fact ellipsoid is really a planetary _shape_ consideration). So there
are 2 choices here:
If you want good compatability with the previous traveller system,
then consider the following:
Composition Density Atmosphere
0 Icy Exotic, Irritant or Corrosive
1 Icy Standard
2 Icy Tainted
3 Light Exotic, Irritant or Corrosive
4 Light Tainted
5 Light Standard
6 Medium Standard
7 Medium Tainted
8 Heavy Standard
9 Heavy Tainted
A Medium Exotic, Irritant or Corrosive
B Heavy Exotic, Irritant or Corrosive
C Heavy Insidious
D Heavy Dense, High
E Medium Ellipsoid*
F Light Thin, Low
* or maybe Insidious if you don't mind incompatibility.
If you need to know whether a given atmosphere is exotic, irritant or
corrosive, then roll 1D: 1-3 Exotic, 4 Irritant, 5-6 Corrosive.
The only real difference here is that 3 goes from very thin to
exotic/corrosive, so concievably a large world could be having its
effective atmosphere type changed from 3 to A or B under the old
system, however the atmosphere density will only change from 3 to 4 or
5.
All in all, I think it should work OK.
Now for the virus story:
Hans Rancke-Madsen [email removed] writes:
>> The Virus is going to make technological advance extremely
difficult in
>>affected areas, however, so that recovery may well be not possible -
every
>>time that a civilisation gets to TL 7 or so, it will almost surely
start
>>using silicon chips,
>
>What's the bet that someone will develop a non-silicon chip before
the
>Cymberline predator has been on the scene 10 years?
Yes, but you seem to have missed the point: is such a substitute going
to be accessible to a TL7 or 8 world? Indeed I think I mentioned that
I would be surprised if your average TL15 ship's computer used silicon
chips. The point still remains: unless the virus is not much of a
threat, there is not going to be any easy way for a world to develop
to TL9 and get interstellar travel (or if they do, it won't be long
before the virus finds them and eats all their electronics).
>
>> Realising the military potential of this discovery for the
Domain of
>>Deneb, the development of stutterwarp drive ships are fast-tracked
and the
>>problems with the electronics surmounted by new (and incidentally
Virus-
>>proof) technologies. By the time the Domain of Deneb is threatened
by the
>>Virus a small squadron of fighting ships is ready. This handful of
ships
>>then defeats a Virus Armada coming through Corridor.
>
>> [Deneb then helps]
>>the Aslan Heirate (in exchange for the Ihatei to stop their
attacks),
>
>The ihatei isn't even a real threat without the virus. With the
Aslans
>plagued by the Virus and Deneb controlling virus-free, stutterwarp
ships
>there's only one way the Aslans are going to get any: As loyal
vassals
>of Archduke Norris.
True, you have a valid point here.
Then again, there is probably no way that Deneb could even contemplate
conquest of the Aslan Heirate (especially if they have had major
problems with virus incursions), just like they could not contemplate
annexing the Zhodani. In addition, the Domain seems to be
non-expansionist. I can see that a hard-pressed Deneb might reach some
sort of agreement with the Aslan (after all, the Domain is really only
fighting the ihatei, not the Heirate itself).
Admittedly, in the long run the Heirate is defenseless against Deneb,
but I s'pose that once it is known that stutterwarp is possible, the
Aslan & Zhodani may well develop it fairly rapidly.
- -or-
Maybe the Hivers help out the Aslan.
Or sell the stutterwarp to them after Deneb has defeated the virus...
Any other suggestions?
It's late. I'd better stop this. 8-)
See ya 'round
Corran Webster
[email removed]