CO System Generation

[cray]

That, however, is a problem. It takes time - LOTS of time. Apparently it took about a billion years on Earth from the moment the planet formed to the point where cyanobacteria had a measureable effect on atmospheric composition; it took 4 billion years or so for life to spread onto dry land.

That's addressed in the habitability modifiers in the Primary Stats table and the optional rules at the end of the section.

whereas the most massive O-type and B-type stars live maybe 10 million years in total.

Hence the commentary in the "Hot, Hot, Hot" section.

So, if you want to go with the science, restrict habitable planets to F-, G- and K-type stars of class V, *possibly* classes IV and VI, plus some or all M-type stars.

Did the habitability modifiers and optional rules on those stars in CO address your concerns, or would you tweak them a bit?

As for placing planets around giant stars, I agree completely; I think BT could do with a retcon that changes all giants and O/B/A stars with habitable planets around them to something scientifically plausible.

There's a partial retcon underway. Most stars with non-main sequence stellar types get tweaked to -V when possible.

[worktroll]

The jury is still of whether life can develop on planets around M-type stars; their Liquid Water Zone is so close to the stars that a planet there would most likely be tide-locked, meaning it has the same side facing the star constantly, much like our moon does to Earth. Since that would mean one side of the planet is constantly scorched by sunlight, while the other is perpetually cold and dark, I´m sure you can see that this would be problematic. There are apparently some models indicating that certain circumstances might allow for life to form, such as if a dense atmosphere helps carry heat from the day side to the night side, but I haven´t seen anything on how likely such circumstances would be - never mind that the dense atmosphere would be wracked by unimaginably massive storms from the temperature differentials on that world. That would rule out most or all of the M-type stars, which is kind of a problem because those make up about 75% of all stars out there.

Leaning on the "jury likely to decide yes" side, myself. One-face worlds will certainly have less than ideal locations - sub-solar point, and the antipode, for example - but there's likely to be a considerable ring around the terminator with viable conditions.

Yes, there are dependancies - atmospheric density, and a funny little thing called "scale height", which relates to the surface gravity and how rapidly air density falls off with altitude, which also has a lot to do with atmospheric transmission of heat. The EBMs - Energy balance models - for climate I used to work with (30-40 years ago) would have been ideal for modelling this ...  :(

A larger problem is the tendency for red dwarves to be flare stars - major solar flares with enhanced UV. As close as a world would be, they would be ... dramatic.

[BLOODWOLF]

Ok this spreadsheet is done.  1 - 15 slots, ten different stable orbital resonances that it rolls for each time with every slot (press F9 to recalculate sheet), correct/close mass, radius, temp, and luminosity values.  White dwarf stars never have a slot in the life zone (too small of an AU) *shrugs* I mean that would make sense would it not?  White dwarfs have already been through the main sequence, red giant and swallowed up any nearby planets, and now is a dwarf....that system is dead.



Removed the sub-giants and white dwarfs from the 480 stars where they dont show up on the chart to be more accurate.

[NeonKnight]

Ok this spreadsheet is done.  1 - 15 slots, ten different stable orbital resonances that it rolls for each time with every slot (press F9 to recalculate sheet), correct/close mass, radius, temp, and luminosity values.  White dwarf stars never have a slot in the life zone (too small of an AU) *shrugs* I mean that would make sense would it not?  White dwarfs have already been through the main sequence, red giant and swallowed up any nearby planets, and now is a dwarf....that system is dead.



Removed the sub-giants and white dwarfs from the 480 stars where they dont show up on the chart to be more accurate.

Awww....I like the idea of a white dwarf having a Life Zone :D

I play a lot of Elite Dangerous (they have a really good Stellar Forge in that game it seems), and one of my most WOW moments was finding a terrestial Water World in orbit of a White Dwarf:



and a nice shot of my Ship too in orbit of the water world with the White Dwarf the 'BRIGHT STAR' to the left.

I know it would be nice to know the math behind Frontier's Stellar forge engine, so good, it even 'predicted' the Trappist System:

http://mashable.com/2017/02/26/elite-dangerous-trappist-1-nasa-discovery/#yI6fXK39QaqQ

[Sir Chaos]

That's addressed in the habitability modifiers in the Primary Stats table and the optional rules at the end of the section.

Hence the commentary in the "Hot, Hot, Hot" section.

Did the habitability modifiers and optional rules on those stars in CO address your concerns, or would you tweak them a bit?

There's a partial retcon underway. Most stars with non-main sequence stellar types get tweaked to -V when possible.

I don´t have CO. I thought I had mentioned that previously? I have little doubt you did a stellar (pun intended) job there, but I can´t comment on what I never read.

I wholeheartedly agree with the retcon, though, FWIW.

[Frabby]

There's a partial retcon underway. Most stars with non-main sequence stellar types get tweaked to -V when possible.

BattleTech may have been ahead of its time. As far as I gathered, planets have by now been found in a lot of places previously thought unlikely; and the goldilocks zone around a star isn't an absolute requirement for habitability either. There are always ways to explain how life could exist in unlikely places under the right circumstances.

[Sir Chaos]

Awww....I like the idea of a white dwarf having a Life Zone :D

I play a lot of Elite Dangerous (they have a really good Stellar Forge in that game it seems), and one of my most WOW moments was finding a terrestial Water World in orbit of a White Dwarf:



and a nice shot of my Ship too in orbit of the water world with the White Dwarf the 'BRIGHT STAR' to the left.

I know it would be nice to know the math behind Frontier's Stellar forge engine, so good, it even 'predicted' the Trappist System:

http://mashable.com/2017/02/26/elite-dangerous-trappist-1-nasa-discovery/#yI6fXK39QaqQ

That could be a rogue planet captured after the star turned into a white dwarf - which would explain the high orbital eccentricity. It would also explain why the water and atmosphere (or even the planet itself) weren´t burned away during the star´s giant phase.

[NeonKnight]

That could be a rogue planet captured after the star turned into a white dwarf - which would explain the high orbital eccentricity. It would also explain why the water and atmosphere (or even the planet itself) weren´t burned away during the star´s giant phase.

Yep, my thoughts too. Waaaaaaaaaaaaaaaaaaaaaaay to close to not have been burned away during the red Giant stage. But still, a fun find for me.

Just realised, the SHIP SHOT never made it :/

[Daryk]

If it's tidally locked, shouldn't it have two temperatures (day side/night side)?

[BLOODWOLF]

I might change the formulas to try and get a life zone in these <1 mass stars, just did Chaos' orbital resonance thing (always >1) * the previous planet's AU.  Could multiply it by the star's mass like how CO is done but will need to add each result to the previous instead so dont end up with 0.17 * 0.89 and get smaller and smaller AU for the slots.  And these Ia supergiants are only around 20 Masses now (which matches Wikipedia)  instead of 400+ like before.

[NeonKnight]

If it's tidally locked, shouldn't it have two temperatures (day side/night side)?

If you are referring to the ELITE DANGEROUS image, I think all their measurements are averages, so, Day TEMP & Night TEMP averaged.

[Daryk]

Yes, that's what I meant... an average in that case isn't particularly informative, unfortunately.

[cray]

I don´t have CO. I thought I had mentioned that previously?

D'oh! Skimmed too fast, sorry.

[BLOODWOLF]

I still cant get subdwarfs (VI) or whitedwarfs(VII) to have slots in the habitable zone.  Looking through the planets.xml min temp of all the planets is -20C (Mannedorf) max is Dustball (71C) so i think the max should be 70C and Min....idk this should be limits on what is human colonizeble over what actually will support life I think.

[worktroll]

With domes, underground cities, and a lot of cash to splash, -20C and 70C are entirely livable. Which isn't quite the same thing as you're considering, I know.

If there's sufficient interest - eg minerals, or border post - the planet will be settled. See Halstead Station, with it's atmosphere of argon and cyanide compounds  :o !

[Hammer]

With domes, underground cities, and a lot of cash to splash, -20C and 70C are entirely livable. Which isn't quite the same thing as you're considering, I know.

-20 C, as Canadian that's when I put a sweater on  :))

I think -60 C to 70c would be a good temperature range, but gravity could be a bigger issue.

[BLOODWOLF]

Ok I think the max avg temp should be 71'C 344'K (Dustball).
Max lowest temp.......I dont know.  And these are planet-wide average temperatures of the planets from pole to pole so if its avg temp is -70 then the poles are how much colder?  Would man settle this iceball being so cold and would it have any resources worth the effort?  The maximum min temp is going to help the most with getting a planet in the habitable zone around these VI and VII stars (especially the M cold suns where the life zone is around 0.01 AU)  still looking like class VI and VII stars are just going to be SOL for having habitable planets. 

*Edit:  Im going with +73 and -73 C (346K / 200K) as the upper and lower limits for planets within the habitable zone that man would colonize.

[BLOODWOLF]

Final product.  Will just have to create a check in the code for:

Code: [Select]

If (1.211 * mass) > outerLife Then
'generate a new star
While (1.211 * mass) > outerLife
spectralClass = getSC()
subtype = getST()
luminosity = getL()
spectralType = getST()
End While
Else
End If
Because VI and VII stars are not going to work (VI does sometimes for the big hot stars past K I believe).  Current method sometimes gives me up to 4 habitable planets and not always in the same range of slots so, Im happy with it.

[Sir Chaos]

-20 C, as Canadian that's when I put a sweater on  :))

I think -60 C to 70c would be a good temperature range, but gravity could be a bigger issue.

Don´t forget that those are average temperatures, presumably in the middle latitudes.

Even in pre-industrial (and thus before any "climate control" other than open fires) times, people on Earth settled in places with temperatures ranging from what... -10°C to 50°C? 0°C to 40°C? And temperature varies fairly wildly by latitude, so even with more or less complete loss of technology during the Succession Wars, temperature would not a planet completely uninhabitable as long as there are latitudes in which temperatures are within the above range - the equatorial regions of cold planets, or the arctic/sub-arctic regions of hot planets.

Air pressure would also be a limiting factor - at higher pressures, low-lying regions might be uninhabitable, while at lower pressure, high altitudes might be near vacuum. IIRC the former is the case on Hesperus II, while the latter showed up on the periphery world where the Northwind Highlanders fought that Smoke Jaguar galaxy... Wayside, I think. There´ll be some planets where air pressure is too low even at sea level, and some with high air pressure and few or no highlands far enough up to provide sufficiently low air pressure, but those probably won´t be many. Well, there will be many worlds with too low an air pressure, but few of those will have complex life because they won´t have liquid surface water.

[BLOODWOLF]

Yeah, we decided on slack that this should be more of what temperature limits for the life zone could planets be that man would colonize over what would actually support life.  And keeping in mind its the avg temp from pole to pole, i know.  Pressure and gravity and all that will be after this right now just worried about getting a system working for coming up with system positions for the planets.

[BLOODWOLF]

It works! ......sorta

[BLOODWOLF]

Gwithian has an impossible star K6IV (sub-giants dont exist for stars colder than K3) and no system position so makes my code array index out of bounds exception.

[BLOODWOLF]

Baxley also has an impossible K5IV star, Redfield has an impossible K5IV, Tall Trees with a M2IV, Telos IV with a K7IV, Tokasha with a K5IV, Victoria with  K7IV, Muana Loa with a M6IV, Frobisher with a K5IV, and Dunklewälderdunklerflüssenschattenwelt (Bob 2822+) with a M1IV.

Some of these planets Im going to have to have it redo the system position because some have a star and position defined but no temp or gravity and all that.  Im doing the planetary temp off the real world formula as if the planet has an Earth like atmosphere and if it doesnt perform the slots subroutine for finding a sysPos then it has no idea what distance from the star position 5 is for example.

[monbvol]

I happen to be working on a project where I could use a utility like this to complete it.

Any chance I could convince you to PM me a link where I can download it?

[BLOODWOLF]

I'm currently working on building it right now.  Only have the star variables, system position, axis and orbit fields done so far.  And just broke it last night lol.  If I can fix it will finally get to Jayof9s planet generation sheet and fill out the rest but, this xml part is mainly for just filling out data that is empty in MekHQ's planets.xml.  What is your project about?

[monbvol]

I have a full conversion AU I've been working on.  I've managed to get a fair portion of it translated to MekHQ thanks to the easy to edit XML files but I could use a way that is a lot less tedious to fill in the star types and even primary inhabited orbital position.

So this looks really helpful toward that end.

[BLOODWOLF]

Oh, I already got star and sysPos covered.  Should get on the slack channel where Im working on this with Hammer and Jayof9s

[BLOODWOLF]

Code: [Select]

Mauna Loa
Geophysical
System position 6th[1]
Jump point
distance 2.34 days[1]
Moons None[1]
Surface gravity 0.78[1]
Atmospheric pressure High (Toxic)[1]
Equatorial temperature 347°C (Inferno)[1]
Surface water 68%[1]
Highest native life None[1]
Reference Year 3095[1]
68% surface water on a planet with an avg temp of 347.....really?

[monbvol]

When I say full conversion I mean I'm not even using the same map, factions, or designs.  It is very extensive.

So something that can let me randomly generate about 100 stars and which orbit their habited planet is in or so and export it in a plantes.xml friendly format would be most welcome.  Even if I had to copy paste the output.

Factions and designs were easy and I even managed to figure out how to implement most of my construction based house rules and a couple game play ones.

RATs, maybe altering the files that randomly generate pilot names, and waiting for MegaMekLab to cover the remaining unit types are on my to do list for it.

I do have a link to a rather outdated* version of MekHQ that I have cobbled together in a thread linked in my signature if you want to take a look at what I'm talking about.

*The version of MekHQ is very out of date.  Very is not a strong enough word I think in this case.  But the planets.xml file should actually be fairly accurate but I know I've done some work on it since last uploading it.

[NeonKnight]

Would be cool if you could convert the maps made by this software to megamech on the fly:

https://secure.profantasy.com/products/ft.asp