UWP Changes

[robject]

Not known to me. The Khurda I have has no water, indeed, but is a Fl world, not a desert:

</font><blockquote>code:</font><hr /><pre style="font-size:x-small; font-family: monospace;">Khurda 1036 D9D469B-6 S Ni Fl 304 Im K4 V </pre>[/QUOTE]HOWEVER, the example 'regenerated' UWP is a desert world:

</font><blockquote>code:</font><hr /><pre style="font-size:x-small; font-family: monospace;">1036 Khurda D860858-5 S De Ri Pr 4111 Im M V M V </pre>[/QUOTE]

 

[jfetters]

:slaps hand on forehead:

Sorry! I meant to say that I was using the updated UWPs that you regenerated.

So the point was that there was an issue in the regen with that world not being able to be a desert with the size and atmosphere.

Hydrographics is 2D6 - 7 + size. So it is impossible for a size 8 world to be a desert. Just wanted to make sure your regen code would catch those kinds of things, that's all.

Also, your PBG is four digits. What is the fourth and what is their order?

 

[robject]

That's a great point.

 

[robject]

The UWP has a few... experimental pieces to it. The PBG in the regen files is actually the PBRG file, where 'R' is the number of "rockball worlds" in the system. That group may be replaced by PBGO, where 'O' is the orbit number of the mainworld.

Or maybe we'll just keep using PBG.

The regeneration code is different from the generation code, which means it has bugs in it. The bugs all have to do with the relationships between the UWP digits. You've just found a subtle one.

It would be safer for me to only use the straight generation code, and run it on each world until the results match the AOTI fingerprint:

</font><blockquote>code:</font><hr /><pre style="font-size:x-small; font-family: monospace;">$uwp = randomWorld() until $uwp matches AOTI fingerprint;</pre>[/QUOTE]

 

[jfetters]

Rockball! Okay! I thought I was going to go crazy trying to figure out what that was.

In any case, my vote would be to either use the PBGO, as it seems to me the orbit # would be more useful than "rockball," or just keep the plain old PBG.

Also, from a code simplification perspective, the "regen until matched" approach is certainly faster.

 

[robject]

I agree that PBGO is more useful. You're validating my suspicions. So I'm throwing away Rockball.

Regen until matched is slower... except when you're talking about debugging an algorithm... so yeah.

 

[aramis]

Orbit No. + stellar type = source of year length.

I like PBRGO, but at that point, one is dangerously close to expanded gen....

 

[robject]

Agree, and I'm not sure expanded gen is a good idea.

 

[Malenfant]

Well you know, heaven forbid that anyone should try to expand a system that evidently doesn't provide enough information as it is...

I really don't understand this attitude at all. If something can be changed to make it either more understandable or useful then why not just do it? If it's a case of having to persuade MWM that this is a better way to present the data then why not start making efforts to persuade him? Or is he just not going to listen regardless of any potential benefits (which I wouldn't put past him).

 

[robject]

Quite so. In fact, adding more cruft to the UWP might not be as useful as simply indicating the orbit in descriptive text, plus for do-it-yourselfers, a small table indicating the likely habitable zone based on primary.

 

[Peter Newman]

I have a somewhat radical change to suggest, but it won't require redoing any worlds not in this solar system.

Change size from 'Diameter in thousands of miles' (EARLY CT) [1] to '_radius_ in thousands of _kilometers_. This will make every world almost 25% bigger and not quite twice as massive.
More massive planets can hold thicker atmospheres. This will cut down on the improbable number of moon to mars sized planets with earth density atmospheres.

This would change Earth to size 6, and this would result in a large number of large high gravity worlds but better that than what we have now. It would also get rid of the last vestage of the Imperial system in the rules.

 

[aramis]

It also has the advantage of making worlds of nearly 2G without breaking the system nor adding higher densities.

But it also means redefining Tprime, Tsec, and all the landing tables, and gives us (inconveniently) earth being about 6.3. Smack dab between 6 and 7, since d≅12,756.3 km (nineplanets.org) and thus r≅6378km.

Some quick figures:
</font><blockquote>code:</font><hr /><pre style="font-size:x-small; font-family: monospace;">r S(xE) M(xE) Gs(@SG=1E)
1000 0.157 0.004 0.162
2000 0.314 0.031 0.314
3000 0.47 0.104 0.471
4000 0.627 0.246 0.626
5000 0.784 0.482 0.784
6000 0.941 0.833 0.941
7000 1.097 1.32 1.097
8000 1.254 1.972 1.254
9000 1.411 2.809 1.411
10000 1.568 3.855 1.568</pre>[/QUOTE]which gives a nearly 5-9% difference from earth and 1G.

Now, at s=1100km
</font><blockquote>code:</font><hr /><pre style="font-size:x-small; font-family: monospace;">
r S(xE) M(xE) Gs(@SG=1E)
1100 0.172 0.005 0.169
2200 0.345 0.041 0.344
3300 0.517 0.138 0.516
4400 0.69 0.329 0.691
5500 0.862 0.641 0.863
6600 1.035 1.109 1.035
7700 1.207 1.758 1.207
8800 1.38 2.628 1.38
9900 1.552 3.738 1.552
11000 1.725 5.133 1.725</pre>[/QUOTE]size 6 is only 3% over

Of course, if we assume the 2% stronger G of traveller (Vland, perhaps? Or Sylea?) and set that to size 7 "Default" (moving earth off both the G and D defaults), we get the following:
S G
1 0.143
2 0.286
3 0.429
4 0.571
5 0.714
6 0.857
7 1.000
8 1.143
9 1.286
A 1.429

 

[Malenfant]

Originally posted by Peter Newman:
Change size from 'Diameter in thousands of miles' (EARLY CT) [1] to '_radius_ in thousands of _kilometers_. This will make every world almost 25% bigger and not quite twice as massive.
More massive planets can hold thicker atmospheres. This will cut down on the improbable number of moon to mars sized planets with earth density atmospheres.

That's be problematic. You're rolling 2d-2 to get radius - the average roll (after modifiers) will be 5, which means a radius of 5,000km - Earth and Venus, as you say, will be size 6. Which means that the most common terrestrial bodies in the universe will be around earth-sized. Most satellites will need major negative modifiers to produce results like those seen in our own solar system (where no satellite is greater than size 3 in your version).

And at the higher end, planets will be so massive that they won't be terrestrial anymore - they'd often snowball into gas giants because they can easily hold onto hydrogen.

If you want to get rid of small planets with earthlike atmospheres, then it makes more sense to fiddle with how atmospheres are generated, not with the size parameters.

 

[Peter Newman]

Aramis wrote

"Of course, if we assume the 2% stronger G of traveller (Vland, perhaps? Or Sylea?)"

As far as I can tell G = 10m/sec was just made up by GDW to make the math easier when calculating travel times. I'd
tend to assume that in the Traveller universe 1 G is also 10m/sec just to make the math easier. Someone, probably during the Terrran Confederation, just decided easier math was good.

Sylea is about 0.69 G, so that's around 6.77 m/sec and a 'standard' gravity is a hair under 1.5 Sylean G's. Vland is 1.15 g or about 11.3 m/sec (At 9.826 m/G)

Aramis also wrote

" and set that to size 7 "Default" (moving earth off both the G and D defaults), we get the following:
S G
1 0.143
2 0.286
3 0.429
4 0.571
5 0.714
6 0.857
7 1.000
8 1.143
9 1.286
A 1.429"

Well I suppose you could do it that way. The way I'd prefer to do it is for the basic system generation to assume a standard density (earths) and for the expanded system generation to allow you to generate an exact planetary density. This expanded system would modify density by atmospheric density (and maybe hydrographics), so that a planet with the physical UPP 266 would be denser than a planet with a physical UPP of 200. Heck you could even modify it by population so that planets with higher populations tended towards more average graviy, rigging density up for smalll worlds, and rigging it down for larger ones to get more comfortable values for local gravity.

 

[Peter Newman]

Malenfant wrote

"quote:
Originally posted by Peter Newman:
Change size from 'Diameter in thousands of miles' (EARLY CT) [1] to '_radius_ in thousands of _kilometers_. This will make every world almost 25% bigger and not quite twice as massive."

That's be problematic. You're rolling 2d-2 to get radius - the average roll (after modifiers) will be 5, which means a radius of 5,000km - Earth and Venus, as you say, will be size 6. Which means that the most common terrestrial bodies in the universe will be around earth-sized."

Yes, thats the point. Earth sized planets with earth like atmospheres are way more plausible than mars sized ones.

Malenfant wrote
"Most satellites will need major negative modifiers to produce results like those seen in our own solar system (where no satellite is greater than size 3 in your version)."

The generation of sattellites _should_ need major modifiers. The system was origionally intended for generating main worlds, and that is still its main use. Satellites should be small, and they should require altering the standard rules. YMMV.

Malenfant wrote
"And at the higher end, planets will be so massive that they won't be terrestrial anymore - they'd often snowball into gas giants because they can easily hold onto hydrogen. "

That is admittedly a problem, but I think you may be looking at it wrong from a Traveller point of view. Any size 10 planet is not going to be a gas giant or it would probably be bigger than size 10. Thus that particular size 10 planet must not be massive enough to retain hydrogen, Ths our gravity generation system should be rigged to model this.

Malenfant wrote
"If you want to get rid of small planets with earthlike atmospheres, then it makes more sense to fiddle with how atmospheres are generated, not with the size parameters."

I really can't see Marc changing the whole 2d6-2 for size, 2d6-7+Size for atmosphere rules. He might be flexible enough to chande what 'Size' means. Thus changing the atmospheric parameters is a non starter from the word go, unless I'm reading Mr Miller wrong.

 

[Malenfant]

Originally posted by Peter Newman:
Yes, thats the point. Earth sized planets with earth like atmospheres are way more plausible than mars sized ones.

This won't help you reach that goal though. All this will do is increase the average size of planets. It's doing nothing to the atmosphere generation at all.

That is admittedly a problem, but I think you may be looking at it wrong from a Traveller point of view. Any size 10 planet is not going to be a gas giant or it would probably be bigger than size 10. Thus that particular size 10 planet must not be massive enough to retain hydrogen, Ths our gravity generation system should be rigged to model this.

A 10,000 km radius planet with earthlike density in the habitable zone is only just shy of holding onto hydrogen, and can easily hold helium. Realistically it's probably going to have a higher density because of self-compression, which makes it more likely to snowball into a gas giant. And in the Middle and Outer zone they can definitely hold onto hydrogen. So you're going to have to keep coming up with exceptional explanations to explain why this isn't the case, and personally I'm dead against anything that deliberately generates exceptions all the time.

I really can't see Marc changing the whole 2d6-2 for size, 2d6-7+Size for atmosphere rules. He might be flexible enough to chande what 'Size' means. Thus changing the atmospheric parameters is a non starter from the word go, unless I'm reading Mr Miller wrong. [/QB]

It's the atmospheres stuff that needs changing, not the size. If he's not willing to do that, then the system is still screwed. In the past he's been unwilling to change anything to make it more realistic.

 

[Plankowner]

The Standard UWP generation method is supposed to be for the MAIN WORLD. This suggestion would at least fix the small world, dense atmosphere problems that pervade the current system.

For those rare Size A mainworlds, those would be lower density versions of pre-GG. OR, if they have ATM B+ (likely), they might really be transition worlds that have some exploitable resource making them desireable. Hydrogen in the atmosphere would definitely make it Insidious, since Hydrogen can seep through just about anything and when mixed with O2, it likes to go boom.

I LIKE this idea. The system generation from LBB6 was broke when it came out and has gotten nothing but worse as more data has become available.

 

[Malenfant]

Originally posted by Plankowner:
The Standard UWP generation method is supposed to be for the MAIN WORLD. This suggestion would at least fix the small world, dense atmosphere problems that pervade the current system.

It wouldn't though - changing to '2d-2 = radius in 1000s of km' just means you're going to get statistically less small main worlds. It does nothing to prevent those small worlds from having atmospheres they can't hold on to.

 

[aramis]

Actually, it does, if you understand the statistical effects.

Since the atmosphere codes would not be changed, the size 4 mars would have a max range of 0-9, rather than as a Size 6, a range of 1-B.

I could crank out the maths, but it's not worth it.

You still have potentially breathable atmospheres on sublunar sized rocks, but the correlation of diameter/radius to atmospheric pressure IS affected, even though the relationship between rolled size and rolled atm is unaffected. That size means a larger chunk of rock.

It does not fix the underlying problem that small chunks of rock can have breathable atmospheres, but it reduces the absolute numbers of submartian worlds generated by redefining the sizes.

 

[Malenfant]

Originally posted by Aramis:
[QB] Actually, it does, if you understand the statistical effects.

Since the atmosphere codes would not be changed, the size 4 mars would have a max range of 0-9, rather than as a Size 6, a range of 1-B.

Erm, under the current system (size = diameter in 1000s of miles) Mars is size 4 (4327 mile diameter). In the new system (size = radius in 1000s of km), Mars would be also size 4 (3390 km radius).