A new size scale for stellar systems

[Malenfant]

Eeee, that'd be complicated. And I think you're thinking of the post I did about gas giant satellites having a fixed mass percentage of their primary?

 

[TheEngineer]

If thats the way, what about producing a full featured solar system genesis simulation starting with some distributed nebula and ending in a dying central star ... somewhere you can press the stop key and say "I'll take that"....

Mal, would You do that ?

 

[Liam Devlin]

Originally posted by Malenfant:
Eeee, that'd be complicated. And I think you're thinking of the post I did about gas giant satellites having a fixed mass percentage of their primary?

Yes, thats the one.

 

[Liam Devlin]

Of course, would that only give us the base number of ejectionable mass for the Gas giant's satellites, not the whole solar system's?

If so, then perhaps once GG's and belts are in the system creation process, and the Sizes of the jovians determined (LGG or SGG), this could be useful into projecting the number of, or approx. size potential of the jovian's satellites?

 

[TheEngineer]

IMHO in a solar system formation setting jovian satellites are nothing but "chaotic dirt" and I would not dare to set up rules for them, based only on their center body mass.

Simulations show, that there is a kind of "degree of initial disturbance" during formation, thats somehow related to the fragmented development of mass centers in the primary disk and thus sub disks or sub sub disk etc...
E.g. in a sim of a perfect cloud without any turbulences, there is no formation of anything.
It needs a spark ...

Perhaps it would make sense to use such a "fragmentation level" attribute to influence the complete (Traveller) system generation process ?

 

[Malenfant]

I'm hesitant to get into a discussion about gas giant satellites given that Tom/Laryssa was one of the people who (along with Aramis, who has been strangely quiet lately) derailed the original thread about the subject with their claims that the science was wrong/flawed and that what they believed was right instead.

 

[Space Cadet]

Originally posted by Malenfant:
Well, politics is a no-go now - the politics board has been removed, anyone talking politics outside gets stomped on by the mods (which we now have, and are decent and timely in their response). So there won't be any talk of politics.

However, it will take more than a new email account to hide your true identity from people - your style just doesn't change at all, whether you're Tom Kalbfus, Laryssa, or Space Cadet. That and the fact that BR spotted you on another forum talking about the same thing, didn't exactly make it hard to figure out who you really were.

What worries me more here is that I know what your attitude to science and realism is. So long as you don't start claiming that science is wrong, or doesn't know anything about planetary formation, or anything like that then there won't be a problem.

Now, my main problem with this table isn't so much about realism, it's more about its necessity. I just don't think anyone ever needs to generate an entire continuum of objects from 1.5 metres in diameter up to 190,000km or whatever. If your stated aim is to come up with codes for objects that Traveller doesn't classify, then why not just add those to the existing system?

Ok, I admit, my system for generating a solar system is a bit ad hoc, but what about just the mainworld? You have a map, and a listing for all the mainworlds, one per hex, what if you wanted a system that could include gas giants and asteroids as main worlds, rather than just planets from 1,000 to 10,000 miles in diameter? It is possible with standard Traveller technology to live within the atmosphere of a gas giant itself, not a satellite thereof but the actual gas giant, all you really need is a way to avoid falling into the crushing depths of the gas giant's atmosphere. In Traveller there is gravitic technology, another method is a hot hydrogen balloon. Since fusion is standard technology in Traveller, what better place for a high tech civilization to exist than in an environment where you are surrounded by fusion fuel? You could have a "cloud city" or a number of cloud cities dotting the atmosphere of a gas giant. A city can levitate either through gravitic technology or by heating the gases inside a giant balloon so that it is less dense than the surrounding atmosphere and thereby providing lift for a city. Since the most convenient energy source is fusion, then we're talking about a civilization that is at least tech level 8, probably 9 would be easier.

Originally posted by Malenfant:
[QB]For example, Book 6 says that S (Small World) is 200km radius. Personally, I say it covers everything from 500 to 1500 km diameter (2d+3 x 100 km diameter). I also add a code T (Tiny) for things smaller than that, for which I use this table:

Roll (1d6) Size T Diameter

1: 4d6 km
2-3: 5d20 + 20 km
4-5: d% + 100 km (00 = 100)
6: (1d6 +3) x 50 km

You roll 1d6, then use the result to determine the length of each of the xyz axes of the object, because it's small enough to not have a spherical shape. That gives you a broad spectrum for all small bodies. Or, I just pick three numbers for each axis and be done with it.

For Jovians I just use a snowballing method (like 2300AD) to build them up from a smaller size.

Quite interesting. What I am looking for was a simple metric that describes the size of an object in three digits. I could use the actual diameter, but that would have a differing range of sizes. The Traveller code uses one digit, but what if you were to substitute that one digit with three?

Terra for example is this

Terra A867A69-F B

The actual diameter of Earth is 12,756.28 km

How about this:

Terra A85.267A69-F B

Jupiter would be:

Jupiter E98.1AA000-0

E is no starport
98.1 is 142,000 km
Jupiter's diameter is 142,984 km, so that't pretty close.
The atmosphere is Exotic A at the most habitable attitude.
Jupiter has 100% fluid coverage underneath its crushing atmosphere, the fluid is liquid hydrogen though.
Jupiter has a population of 0,
a government of 0,
and a law level of 0, as the Jupiter in the traveller campaign OTU is not inhabited, but it could be,
and without a population, it has no technology so therefore 0.

I think gas giants are possibly neglected as potential mainworlds. Not all mainworlds have breathable atmophere's after all, it just also happens that gas giant's also don't have a surface you can stand on.

 

[atpollard]

Space Cadet,
I like your enhanced generation of world sizes, but I don't think that changing the UWP size system is a viable option. It invalidates all previous published data and the size 4 = 4000 miles is too intuitive to discard. It would have been better if the UWP size was x 1000 km radius since Traveller is a metric units game, but it is too late to change CT and all that has followed it.

A multi-digit planet size would only work if the first digit corresponded to the UWP sizes and the other digits filled in the details (like rounding to significant figures), so the UWP could remain unchanged but the detailed size could fill in the missing data. For example, a 198 km diameter world could be listed as size 0.1 or 0.12 or 0.123 in the text description so the referee would know that this sub 1000 mile world was actually about 100 or 120 or 123 miles in diameter.

More detail on gas giants would be nice, but the narrow range of planet sizes and the vast range of gas giant sizes makes a common system for both unlikely. A system for gas giant sizes where 10,000 miles diameter (16,092 km) was a size 1 gas giant and 120,000 miles diameter (193,112 km) was a size 12 gas giant (each size = 10,000 miles diameter) might work to achieve your range of desired sizes without trashing 30 years of existing material. The gas giant and planet sizes could be combined if gas giants used letters where A = 10,000 miles diameter; B=20,000 miles; C=30,000 miles … N=120,000 miles. You would just need a table to index a random number to a size, and this could be adjusted to tailor the system to various design assumptions.

On the subject of orbits, I have no idea how orbits actually work, but I would prefer a system that generates roughly the correct number of orbits in roughly the correct locations based on our best understanding of solar system formation. More orbits than the existing rules are only better if there should be more orbits.

 

[Malenfant]

For gas giants you could just use codes D (SGG) and E (LGG) (I'd keep B and C free for 11,000 and 12,000 mile diameter terrestrials). Then you don't have to stick decimal points in the UWP.

I'd actually call the atmosphere type "C" (Insidious) - remember there's Hydrogen in there, and that seeps into vacc suits etc.

So Neptune would be xDC0xxxx, Jupiter would be xEC0xxxx, etc.

 

[Liam Devlin]

Originally posted by Malenfant:
For gas giants you could just use codes D (SGG) and E (LGG) (I'd keep B and C free for 11,000 and 12,000 mile diameter terrestrials). Then you don't have to stick decimal points in the UWP.

I'd actually call the atmosphere type "C" (Insidious) - remember there's Hydrogen in there, and that seeps into vacc suits etc.

So Neptune would be xDC0xxxx, Jupiter would be xEC0xxxx, etc.

Good reminder Mal of the B & C-class sized worlds. There aren't many in Known space by the UWP's but they do crop up 1-2 a sector, those sneaky High-Grav worlds do.

And Hydrogen, gents, was listed under the JTAS article on "Insidious Atmospheres" as one of those low molecule gases that seeps into HazEnviro suits over time.

Agree with atpollard, the UWP doesn't need *more* added to it, but better ways to explain it.

 

[Pickles]

Originally posted by Malenfant:
So Neptune would be xDC0xxxx, Jupiter would be xEC0xxxx, etc.

Here's a thought - what if there was a permanent settlement, an sort of gravitic atmospheric arcology perhaps, atually within the upper atmosphere of a gas giant? Think Cloud City. This would mean we could give gas giants complete UWPs, e.g. CDC0358-A.

 

[Space Cadet]

Size diameter
0.0 = 0.0 m to 0.7 m
0.1 = 0.8 m to 2.4 m
0.2 = 2.5 m to 7.9 m
0.3 = 8.0 m to 24.9 m
0.4 = 25.0 m to 79.9 m
0.5 = 80.0 m to 249.0 m
0.6 = 250.0 m to 799.9 m
0.7 = 800.0 m to 2.4 km
0.8 = 2.5 km to 7.9 km
0.9 = 8.0 km to 24.9 km
S.0 = 25.0 km to 79.9 km
S.1 = 80 km to 159 km
S.2 = 160 km to 239 km
S.3 = 240 km to 319 km
S.4 = 320 km to 399 km
S.5 = 400 km to 479 km
S.6 = 480 km to 559 km
S.7 = 560 km to 639 km
S.8 = 640 km to 719 km
S.9 = 720 km to 799 km
1.0 = 800 km to 959 km
1.1 = 960 km to 1,119 km
1.2 = 1,120 km to 1,279 km
1.3 = 1,280 km to 1,439 km

 

[Malenfant]

Originally posted by the Bromgrev:
</font><blockquote>quote:</font><hr />Originally posted by Malenfant:
So Neptune would be xDC0xxxx, Jupiter would be xEC0xxxx, etc.

Here's a thought - what if there was a permanent settlement, an sort of gravitic atmospheric arcology perhaps, atually within the upper atmosphere of a gas giant? Think Cloud City. This would mean we could give gas giants complete UWPs, e.g. CDC0358-A. </font>[/QUOTE]Yep. Then you can keep the general UWP format and have GGs as mainworlds - Tom's table becomes unneccessary.

 

[Malenfant]

Originally posted by Liam Devlin:
Good reminder Mal of the B & C-class sized worlds. There aren't many in Known space by the UWP's but they do crop up 1-2 a sector, those sneaky High-Grav worlds do.

Realistically speaking there might be quite a few of these big worlds - especially panthalassics. These are huge, volatile-rich worlds that are 1-3 earth masses, up to half of which might actually be water and atmosphere. They'd usually be found in the middle zone, between the habitable zone and outer zone.

 

[Space Cadet]

Actually, I'm now thinking the table above is too complex How about base 16 instead, it would be a simpe linear scale.

It goes like this:

Digits Size
00.0 = 0 km
00.1 = 100 km
00.2 = 200 km (Small)
00.3 = 300 km
00.4 = 400 km
00.5 = 500 km
00.6 = 600 km
00.7 = 700 km
00.8 = 800 km
00.9 = 900 km
00.A = 1,000 km
00.B = 1,100 km
00.C = 1,200 km
00.D = 1,300 km
00.E = 1,400 km
00.F = 1,500 km
01.0 = 1,600 km (1,000 miles)
01.1 = 1,700 km
...
02.0 = 3,200 km (2,000 miles)
03.0 = 4,800 km (3,000 miles)
04.0 = 6,400 km (4,000 miles)
05.0 = 8,000 km (5,000 miles)
06.0 = 9,600 km (6,000 miles)
07.0 = 11,200 km (7,000 miles)
08.0 = 12,800 km (8,000 miles)
09.0 = 14,400 km (9,000 miles)
0A.0 = 16,000 km (10,000 miles)
0B.0 = 17,600 km (11,000 miles)
0C.0 = 19,200 km (12,000 miles)
0D.0 = 20,800 km (13,000 miles)
0E.0 = 22,400 km (14,000 miles)
0F.0 = 24,000 km (15,000 miles)
10.0 = 25,600 km (16,000 miles)
11.0 = 27,200 km (17,000 miles)
12.0 = 28,800 km (18,000 miles)
13.0 = 30,400 km (19,000 miles)
14.0 = 32,000 km (20,000 miles)
...
24.0 = 57,000 km (36,000 miles)
...
34.0 = 82,600 km
...
44.0 = 108,200 km
...
54.0 = 133,800 km
...
64.0 = 159,400 km
64.1 = 161,000 km

This is fairly consistent with the Traveller Unicode for size. If you drop in two extradigits and a hexadecimal point for all non-standard sized worlds, it becomes fairly clear what size your talking about.

 

[Space Cadet]

How about this My code vs Traveller Code
Orbt Name == UPP ======= MyCode
01 = Mercury G30046A E = G03.10046A E
02 = Venus = G8B0168 E = G07.3B0168 E
*3 = Terra = A867A69 F = A08.067A69 F
^60 Luna == F20076C F = F02.30076C F
04 = Mars == F43056A F = F04.43056A F
06 = Jupiter Large GG == X59.CCA000-0
07 = Saturn= Large GG == X4B.BCA000-0
08 = Uranus= Small GG == X20.5CA000-0

The three digits and hexadecimal point between the Starport digit and the atmosphere type is actually a hexadecimal number with a ones and a sixteens place to the left of the point and a sixteenth place to the right, this hexadecimal notiation stores the size of the world rounded off to the nearest 100 km.

 

[Space Cadet]

The standard unicode size can then be treated as shorthand for my system if you want backwards compatibility, and you just have to remember that S = 200 km or 00.2 under my size scale in hexadecimal.

 

[Malenfant]

If you can add different sized bodies in the existing UWP system (which has already been demonstrated) then your tables are completely unnecessary. Why are your tables easier than using the following instead:

S: Small World (500-1500 km diameter)
T: Tiny World (less than 500 km diameter)
U: Space Station (artificial station)
B: 11,000 mi diameter terrestrial
C: 12,000 mi diameter terrestrial
D: Small Gas Giant (more than 50,000 km radius)
E: Large Gas Giant (less than 50,000 km radius)

For space station - we can't use S for that, we can't use O (for Orbital) because that's confused with 0 (zero), can't use R because that's taken for Ring System... so just call it "U" so it follows on from S and T.

There you go - all the codes you'll need. Without the need to concoct arcane hexadecimal multi-digit tables using arbitrary exponents.

 

[Space Cadet]

I think the standard sizes should be in the center of their ranges rather than at the bottom.
S = 200 km ranging from 100 km to 799 km
1 = 800 km (average 1,600 km) to 2,399 km)
2 = 2,400 km (average 3,200 km) to 4,000 km)
etc.
T: Tiny World (Less than 100 km diameter)
U:? I'm not sure there should be a distinction between an artificial world and an asteroid, people living on an asteroid will modify it to some degree to accomodate them anyway.

I think the Unicode should extend to 15,000 miles to make it a hexadecimal digit
B: 11,000 mi diameter terrestrial
C: 12,000 mi diameter terrestrial
D: 13,000 mi diameter terrestrial
E: 14,000 mi diameter terrestrial
F: 15,000 mi diameter terrestrial

At this point the difference between a terrestrial world and a gas giant becomes somewhat academic, these large terrestrial worlds will tend to accumulate thick and crushing atmosphere, there is no way a human can survive on the surface of them anyway, so the solid surface is just as inaccessable as is the solid surface of Jupiter. Jupiter does have a solid surface after all, its just that its a tiny proportion of the planet's overall diameter. Very large terrestrials will tend to transition into gas giants as they get larger, the exact transition point between one and the other is a matter of semantics.

 

[atpollard]

Originally posted by Malenfant:
For gas giants you could just use codes D (SGG) and E (LGG) (I'd keep B and C free for 11,000 and 12,000 mile diameter terrestrials). Then you don't have to stick decimal points in the UWP.

I basicly agree, but one of SC's original goals appeared to be to increase the number of possible gas giant sizes. LGG and SGG will not do that.

Is there overlap in size between the largest rocks and the smallest gas giants? At what point is it a planet with a thick atmosphere and at what point is it a small gas giant?