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Author Topic: Interstellar Operations Open Beta Test: Solar System Generation: Discussion  (Read 34705 times)

Precentor Martial

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The following thread is for discussion of the Interstellar Operations Open Beta Test: Solar System Generation PDF. You can ask questions of why rules were done in a certain way, a wish list of additions and so on.

Please note, this is NOT a thread for specific errata. Use the "Errata" thread for that work.

bronzite

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I just ran through the creation rules, rolling up a Realistic system using the Basic Star System Construction Sheet.  The rules are pretty straight-forward (although I perchance didn't get a habitable planet, so I'll need to go back and try the full populated planet rules.)  I found the content about the mathematics and astrophysics to be very helpful (somebody's been doing their homework!). 

I will say that the Basic Star System Construction Sheet is very, very inadequate to the task it is supposed to help with -- the star system needs an entire sheet, I think, and each habitable planet should have its own sheet as well.  I actually think that the current Basic Star System Construction Sheet would likely work pretty well as a Inhabited Planet Record Sheet, but as a worksheet and as a way of storing and managing data about Star Systems, the current sheet falls flat.

That said, if I use scrap paper instead, these rules flow smoothly and give a lot more useful information and tidbits about the solar system than the AToW Companion rules do, which is a definite positive.  Well done.

Neufeld

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Comstar decoration?! Is CGL discriminating against Capellans since they get no major rulebook?  :(

"Real men and women do not need Terra"
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We will be used to subdue the Capellan Confederation. We will be used to bring the Free Worlds League to heel. We will be used to
hunt bandits and support corrupt rulers and to reinforce the evils of the Inner Sphere that drove our ancestors from it so long ago."
-- Elias Crichell

Frabby

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First impression: Like. In particular, I like that this system seems to be universal, i.e. useable for virtually any sci-fi setting.
Also, the writing is comprehensive and informative. (Though this is only a first-glance impression; I haven't really read it in-depth yet.) Did Cray write this?

Okay, and here's my personal gripe: Transit times.
What's the point in investing a great deal of effort into a scientifically accurate simulation/description of a realistic star system, only to laugh at all the data and then use that overly simplified travel time diagram from DS&JS? The one that treats all stars as main sequence stars no matter what?

Case in point: Betelgeuse. It's a M2 I sun, which - according to BT tables, which conveniently ignore the (I) - has a 2-day travel from the jump point at a safe distance from the star, to the habitable planet in the lifezone.
Reality check: Fail. Betelgeuse is the single biggest sun we know at this time (afaik), a red supergiant 697 million kilometers in diameter - its diameter is almost 500 times that of our own sun (1.4 million kilometers). The "safe jump distance" is actually well within the sun here! As is the assumed life zone orbit.

The document skips around this by being semi-honest and featuring only (V)-subclass stars. But really, what I would dearly love to see is going full monty and taking the actual size of the sun into consideration. Treating all suns as (V) subtype is a bit like the two-dimensional jump maps that we use because, well, that's how jump maps look like.
« Last Edit: 02 November 2012, 15:37:12 by Frabby »
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SeeM

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I just made a conclusion: you guys are awesome. Roll two dice for a planet distance from a star, and then do astronomical calculations for gravity, temperature, length of a year? That's a Battletech I enjoy. I once was an astronomy amateur, like a 'lite scientist' approach.

In IO planet population depends on it's quality. Great. I was worried that colony creation will be separate from solar system creation.

I also like that the guy creating solar system is named Chuck. He doesn't need a planet, he creates his own.

The "safe jump distance" is actually well within the sun here! As is the assumed life zone orbit.

On page 19 there is explanations for this (Hot, Hot, Hot!). They don't have planets, so why bother? But you got them anyway! :)
« Last Edit: 02 November 2012, 16:28:53 by SeeM »
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cray

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Okay, and here's my personal gripe: Transit times.
What's the point in investing a great deal of effort into a scientifically accurate simulation/description of a realistic star system, only to laugh at all the data and then use that overly simplified travel time diagram from DS&JS? The one that treats all stars as main sequence stars no matter what?

There's several reasons. To begin with:

1) A transit time calculation is provided in the system generation rules so you can get from Point A to Point B in the system, for any system.

2) Stars only spend about 10% of their lives off the main sequence, not counting the white dwarf phase. Thus, about 10% of the stellar population at any time is non-main sequence stars. The "simplified" DropShips & JumpShips / Strategic Operations recharge and transit rules thus address about 90% of the stars in the universe.

3) A suggestion was made to address non-main sequence stars in Strategic Operations' reprint of the transit / recharge rules. However, it was soon realized that separate recharge and transit tables would be required for each other stellar type (VI, IV, III, II, Ia, Ib), thus adding 12 new tables to address about 10% of the stellar population while 2 tables covered 90%. So, that didn't happen in Strategic Operations.

4) FASA writers were wild about using non-main sequence stars. (Your example of Betelgeuse was on my mind when I made the pitch for the expansion in StratOps, and I deliberately used it in the system generation rules for the same reason.) The House Sourcebooks run about 40-50% non-main sequence stars. Because of FanPro / CGL standing orders for reprinting star systems, all those would have to be retconned to use the hypothetical new Strategic Operations' recharge and transit rules. So, the new transit and recharge tables weren't added to Strategic Operations.

5) For the past 4 years, CGL has seen some informal effort to ensure all new habitable star systems described in BT are main sequence stars.

As a result, the system generation rules for IntOps conclude the "Hot, Hot, Hot" system option (pg20 of the .pdf) by being straightforward and giving you the blunt truth: BT is sticking to the Strategic Operations' transit and recharge rules. (Here, you've learned why: there was no room in Strategic Operations for the necessary changes, and the required retcon was too big.) The rest of the document gives you realistic warnings on why making non-main sequence star systems has some difficulties and thus should be avoided.

Quote
The document skips around this by being semi-honest and featuring only (V)-subclass stars. But really, what I would dearly love to see is going full monty and taking the actual size of the sun into consideration.

The system transit rules and JumpShip recharge rules are located in Strategic Operations, not Interstellar Operations. If you can convince Herb to errata 6 new transit tables and 6 new recharge tables into Strategic Operations, and also to retcon all published non-main sequence stars to conform to the new rules, then I'll be happy to cook up the errata for Strategic Operations.

On another topic, this issue should've been raised here first rather than posed as an errata:

Quote
Factual error: The Oort Cloud is not a belt, and it's even highly arguable whether it can be described as asteroids. And it definitely doesn't occupy an orbital slot - its very nature is being a cloud of matter outside of the accretion disk and outside of the orbits. In a sense, it's not even part of the system anymore.

The inner Oort Cloud is hypothesized to be donut-shaped - a belt. Furthermore, as soon as I left out provisions for including the Oort cloud, another player would ask how to make it. Thus, the compromise was to address the (inner) Oort Cloud as an "asteroid" belt and note in the text that the "asteroids" might, in fact, be "icy outer system" objects.
Mike Miller, Materials Engineer

**"A man walks down the street in that hat, people know he's not afraid of anything." --Wash, Firefly.
**"Well, the first class name [for pocket WarShips]: 'Ship with delusions of grandeur that is going to evaporate 3.1 seconds after coming into NPPC range' tended to cause morale problems...." --Korzon77
**"Peace is that brief glorious moment in history when everybody stands around reloading." --Thomas Jefferson, or not

Disclaimer: Anything stated in this post is unofficial and non-canon unless directly quoted from a published book. Random internet musings of a BattleTech writer are not canon.

Frabby

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Thanks for the explanations Cray. To wit, I raised the point because Randall specifically asked for a wish list.  :) You have briefly discussed the issue of transit times with me before, though it may have been in PMs.

On another topic, this issue should've been raised here first rather than posed as an errata:

The inner Oort Cloud is hypothesized to be donut-shaped - a belt. Furthermore, as soon as I left out provisions for including the Oort cloud, another player would ask how to make it. Thus, the compromise was to address the (inner) Oort Cloud as an "asteroid" belt and note in the text that the "asteroids" might, in fact, be "icy outer system" objects.
Sorry; I figured it was a factual error and should go into errata instead (again, precisely because Randall wrote above that this thread isn't meant for errata).
I've just read up on the Oort Cloud on wikipedia. I wasn't aware of the disk-shaped inner Oort Cloud (aka Hills Cloud). You might want to use that name instead. I still maintain that the wording is misleading, especially in the context of a section about filling orbital slots.
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cray

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Clarifying "inner Oort Cloud" or "Hills Cloud" would be easy enough. Will do.
Mike Miller, Materials Engineer

**"A man walks down the street in that hat, people know he's not afraid of anything." --Wash, Firefly.
**"Well, the first class name [for pocket WarShips]: 'Ship with delusions of grandeur that is going to evaporate 3.1 seconds after coming into NPPC range' tended to cause morale problems...." --Korzon77
**"Peace is that brief glorious moment in history when everybody stands around reloading." --Thomas Jefferson, or not

Disclaimer: Anything stated in this post is unofficial and non-canon unless directly quoted from a published book. Random internet musings of a BattleTech writer are not canon.

Jaeger2000

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I guess I'm in the minority, but I was bored out of my skull reading it. Math, equations and the likes are... well not something I enjoy in my spare time.

cray

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I guess I'm in the minority, but I was bored out of my skull reading it. Math, equations and the likes are... well not something I enjoy in my spare time.

Not a problem, it was anticipated not everyone would prefer these in-depth system generation rules. For those folks, the A Time of War Companion has the "quick start" version of system creation. You roll some dice and get quick results without the boring discussion or math.

ATOW:Companion is available for purchase by download now if you'd prefer to try out that system.
« Last Edit: 02 November 2012, 21:40:25 by cray »
Mike Miller, Materials Engineer

**"A man walks down the street in that hat, people know he's not afraid of anything." --Wash, Firefly.
**"Well, the first class name [for pocket WarShips]: 'Ship with delusions of grandeur that is going to evaporate 3.1 seconds after coming into NPPC range' tended to cause morale problems...." --Korzon77
**"Peace is that brief glorious moment in history when everybody stands around reloading." --Thomas Jefferson, or not

Disclaimer: Anything stated in this post is unofficial and non-canon unless directly quoted from a published book. Random internet musings of a BattleTech writer are not canon.

Crunch

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It seems odd to me that Star league facilities are more common than Colonies... are there any plans to provide alternate era versions of the special features chart?
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Jaeger2000

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For those folks, the A Time of War Companion has the "quick start" version of system creation. You roll some dice and get quick results without the boring discussion or math.

Excellent.  O0

cray

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It seems odd to me that Star league facilities are more common than Colonies... are there any plans to provide alternate era versions of the special features chart?

I can look into juggling results of the table. I'm not sure how much room for expansion and extra tables there is.
Mike Miller, Materials Engineer

**"A man walks down the street in that hat, people know he's not afraid of anything." --Wash, Firefly.
**"Well, the first class name [for pocket WarShips]: 'Ship with delusions of grandeur that is going to evaporate 3.1 seconds after coming into NPPC range' tended to cause morale problems...." --Korzon77
**"Peace is that brief glorious moment in history when everybody stands around reloading." --Thomas Jefferson, or not

Disclaimer: Anything stated in this post is unofficial and non-canon unless directly quoted from a published book. Random internet musings of a BattleTech writer are not canon.

Crunch

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I can look into juggling results of the table. I'm not sure how much room for expansion and extra tables there is.

How about just a in era X substitute Y for eras where the Star league facility would be more or less common? Or even making it an 18 (or whatever) place table with era mods sort of like the new model RATS in 3085?
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Atlas3060

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Not a problem, it was anticipated not everyone would prefer these in-depth system generation rules. For those folks, the A Time of War Companion has the "quick start" version of system creation. You roll some dice and get quick results without the boring discussion or math.

ATOW:Companion is available for purchase by download now if you'd prefer to try out that system.
I....I just love you all for making this.
Yes it is very science and math heavy, but I could use this for practically any RPG I want.
I also feel like all this detail will make that particular system or group of worlds characters themselves.

And, of course, I still have the quick and dirty rules for making worlds if I don't feel like going PBS Nova today.
I'm still going through it and even though I might need a few more reads, I like what I see. Tears of happiness.  :'( O0

Are you guys going to do open beta on other parts of this book too? Or sell the whole beta on a reduced price like AToW did?
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Arcologist

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For the "additions wishlist," can something brief, maybe even just a few lines long, be inserted to differentiate between "not easily inhabitable" and "truly uninhabitable?"  I'm thinking of the difference between a place like Sirius V where living is amazingly inconvenient but you can still try to build a colony, versus a place that would have (say) an atmosphere with measurable amounts of HF.

cray

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For the "additions wishlist," can something brief, maybe even just a few lines long, be inserted to differentiate between "not easily inhabitable" and "truly uninhabitable?"

Hmm. That's kind of handled implicitly already. Let me see if this addresses your request (and I'm going from back to front in the .pdf deliberately):

In the Planetary Population Table (of the Colony Creation Chapter), an "uninhabitable" option is mentioned. It is explicitly defined as "planet has a toxic, very thick, vacuum, and/or trace atmosphere." This makes settling the planet difficult, multiplying an population by 0.05. Then there are options for various other marginal conditions (like tainted atmospheres and high gravity) that lower populations to a lesser degree than "uninhabitable."

Likewise, Agricultural Dependence is modified by various negative environmental traits (see USILR Table).

In the system creation chapter, the Habitability Modifier in the Primary Stats table notes when a system is unlikely to have habitable planets. Later, on the Atmospheric Pressure and Habitability Table, there are various modifiers to determine if the planet is habitable. Finally, the Habitable Planet Features Table assigns various features (e.g., tainted atmosphere) that play into the colony creation chapter I mentioned above.

Otherwise, where else in the document would you feel it is useful to spell out "not easily inhabitable" and "truly uninhabitable"? (Not a rhetorical question. If you've read the document, then you'll note I have no trouble interrupting hard rules with fluff or a science discussion. I'll be happy to add the definitions.)

I....I just love you all for making this.

Send hearty thanks to "Fallguy" (who hasn't been seen on CBT.com in quite some time) for the Primary Stats table and to Worktroll for some of the atmosphere work. I was the grunt who filled in most of the rest and is probably responsible for all errors, incomprehensible sentences, and heavy math. There's also been several teams of reviewers who looked over this and provided great input.

Quote
Are you guys going to do open beta on other parts of this book too?

I'm not in a position (galley slave) to comment on future releases.
Mike Miller, Materials Engineer

**"A man walks down the street in that hat, people know he's not afraid of anything." --Wash, Firefly.
**"Well, the first class name [for pocket WarShips]: 'Ship with delusions of grandeur that is going to evaporate 3.1 seconds after coming into NPPC range' tended to cause morale problems...." --Korzon77
**"Peace is that brief glorious moment in history when everybody stands around reloading." --Thomas Jefferson, or not

Disclaimer: Anything stated in this post is unofficial and non-canon unless directly quoted from a published book. Random internet musings of a BattleTech writer are not canon.

theothersarah

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These are rather neat. Not as crazy complicated as GURPS Space's rules and not as fast as the ATOW Companion rules, but it has all the important stuff. I'd even say that it's quite a bit more useful tha ATOW Companion, with tons more useful stats like year length and such, but with the disadvantage that it's a little too crunchy to do "in real time" in say an exploration campaign. But since that's not the scope of Interstellar Operations that's not a problem at all.

I feel the math formulas could use better formatting, though. I don't like how they look like the display on a single-line scientific calculator. Would be nice to see proper fractions and radicals.

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Cray you magnificent bastard!  I've read your book!

 :P

I'll have to print this up and read it to give it a full review but I can already identify your influence more than anyone else's Cray.

Acolyte

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Awesome work!

pg. 25 when explaining how to work the modifiers:
Quote
Modifiers are cumulative; a colony of 100,000 would apply both +1 for a population of under 100 million and +1 for under 100,000 .
If I read the tables correctly, that final modifier should be for under 1 million, not under 100,000.
Hope it helps!

Thank You
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Crunch

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I think this is a minor errata. On p 10 when discussing moon generation the pdf directs the reader to refer to the rules on generating small asteroids, this agrees with the first listing under the heading Asteroid Belts on page 9.

However in the rules for generating Asteroid diameter the smallest class is "Minor" Asteroids. It seems like the classification term should agree between the three mentions.
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Scotty

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Not sure if an error or deliberate:  Are the life zones for some stars supposed to have exactly zero chance of having an orbit fall within them?  Rolled up an M6V, only to discover that the first orbit started at 0.08 AU and the life zone ended at 0.079.
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VhenRa

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Anyone else having a big headache with the year length calculation.

My Scientific calculator refuses to understand the example...

MadVoorpak

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The physics, mechanics and sciency person in me Squeeee'd with joy and died upon reading this.

The more rational, time orientated me died at the prospect of all that work into creating a system.

Still, I know I'm going to build something.

 
I love you guys.

Mukaikubo

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Not sure if an error or deliberate:  Are the life zones for some stars supposed to have exactly zero chance of having an orbit fall within them?  Rolled up an M6V, only to discover that the first orbit started at 0.08 AU and the life zone ended at 0.079.

If I can clarify this, I'm 99% sure it's an error, because I checked every other star in the habitable-biased table (Yep) and no other has 0 chance of a life zone planet. Even M8V does!

I like the rules; I am an old GURPS Space hand and will always love those rules more than reasonable, but this is more than good enough for a Battletech setting.

One thing I will say is that I take issue with the note to the effect of even 'life-generating' stars' chances of having an inhabitable planet is way too high. Specifically, on page 11,

Quote
It should also be noted that the incidence of habitable
planets using this chart is far above the norm for  BattleTech
(which is about 1 habitable planet per 1,000 systems in the
Inner Sphere), let alone reality. This is done for playability.

It would be much more accurate to say, as you did earlier on a separate subject, that there's no good scientific basis to predict how common inhabitable planets are- the stats in here may be entirely accurate! (As an aside, I get something around a 5% chance of a habitable planet in every orbital inside a life zone, though it is entirely possible I flubbed the conditional probability equations I checked). I have seen estimates of the number of F-G-K type stars with a technically inhabitable planet or moon range from anywhere from one in ten thousand to one in two! One in twenty, like what I think these rules give, is a good guess but again there's no scientific certainty to that and I'd prefer to see that noted. It is a quibble.

Another thing: I think it would actually be a good idea to (similar to GURPS Space) allow people to make the planet first, and then build a star system around that world as a fixed point. It's doable with these rules, but a paragraph or two explicitly calling that out as a good option and giving the best way to do it would be very appreciated.
« Last Edit: 03 November 2012, 08:52:29 by Mukaikubo »

cray

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Awesome work!

pg. 25 when explaining how to work the modifiers:If I read the tables correctly, that final modifier should be for under 1 million, not under 100,000.
Hope it helps!

Thank You
   - Shane

Yep. Please report that in the errata thread.

Not sure if an error or deliberate:  Are the life zones for some stars supposed to have exactly zero chance of having an orbit fall within them?  Rolled up an M6V, only to discover that the first orbit started at 0.08 AU and the life zone ended at 0.079.

I can fiddle with the base orbital diameters, but the rules was working with G and F-type stars. Have you found any other stellar types (other M sub-types, K, G, F, etc.) whose life zones don't match up with the planet orbits?

[edit] Looks like Mukaikubo has checked others. I'll go through and tweak the orbital diameter results to get a planet in the life zone.

Anyone else having a big headache with the year length calculation.

My Scientific calculator refuses to understand the example...

T = 2 x Pi x sqrt [R^3 / (G x M) ]

In the pg8 example, you've got a star with a mass of 3x10^30 kg, a gravitational constant of 6.674x10^-11, and a planetary orbital radius of 3.6x10^11 meters. Filling out the equation:

T = 2 x Pi x sqrt [3.6 x 10^11^3 / (6.674x10^-11 x 3x10^30) ]

Per the order of operations, taking care of the paranthetical terms first:

R^3 = (3.6 x 10^11)^3 = 4.6656x10^34
(G x M) = (6.674x10^-11 x 3x10^30) = 2.0022x10^20

And then divide those two, completing the work inside the parentheses:

[R^3 / (G x M) ] = [ 4.6656x10^34 / 2.0022x10^20] = 2.3302x10^14

Then you apply the square root:

sqrt [R^3 / (G x M) ] = sqrt (2.3302x10^14) = 15,265,133

Then you multiply by 2 and Pi:

T = 2 x Pi x sqrt [R^3 / (G x M) ] = 2 x Pi x 15,265,133 = 95,913,533 seconds

And to convert seconds to years:

95,913,533 / 31,536,000 = 3.04 years

How are you applying parentheses in your calculator? I've attached a picture on my TI-85 of how I set it up.
Mike Miller, Materials Engineer

**"A man walks down the street in that hat, people know he's not afraid of anything." --Wash, Firefly.
**"Well, the first class name [for pocket WarShips]: 'Ship with delusions of grandeur that is going to evaporate 3.1 seconds after coming into NPPC range' tended to cause morale problems...." --Korzon77
**"Peace is that brief glorious moment in history when everybody stands around reloading." --Thomas Jefferson, or not

Disclaimer: Anything stated in this post is unofficial and non-canon unless directly quoted from a published book. Random internet musings of a BattleTech writer are not canon.

Paint it Pink

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First skim through and I'm impressed. Looks good to me.

I'm going to go away and see if I can now generate stats for Mummerset, the planet my BattleTech campaign is set on and see if they produce something that works for my Dark Age periphery campaign.
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cray

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I'm going to go away and see if I can now generate stats for Mummerset, the planet my BattleTech campaign is set on and see if they produce something that works for my Dark Age periphery campaign.

Note that if you're trying to create a pre-existing star system, random rolls in these rules are VERY unlikely to deliver your star system. Sticking to straight rolls, you're likely to get an uninhabitable system, and any habitable planet will probably differ from your pre-existing planet. That's why even the example of Chuck's Amtor-II starts off with, "Chuck wants a habitable planet, so he makes it so."

Hence the opening statement in these rules that they're just guidelines to help you along if you have no specific ideas for your dream planet/system/colony.
Mike Miller, Materials Engineer

**"A man walks down the street in that hat, people know he's not afraid of anything." --Wash, Firefly.
**"Well, the first class name [for pocket WarShips]: 'Ship with delusions of grandeur that is going to evaporate 3.1 seconds after coming into NPPC range' tended to cause morale problems...." --Korzon77
**"Peace is that brief glorious moment in history when everybody stands around reloading." --Thomas Jefferson, or not

Disclaimer: Anything stated in this post is unofficial and non-canon unless directly quoted from a published book. Random internet musings of a BattleTech writer are not canon.

VhenRa

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Yep. Please report that in the errata thread.

I can fiddle with the base orbital diameters, but the rules was working with G and F-type stars. Have you found any other stellar types (other M sub-types, K, G, F, etc.) whose life zones don't match up with the planet orbits?

[edit] Looks like Mukaikubo has checked others. I'll go through and tweak the orbital diameter results to get a planet in the life zone.

T = 2 x Pi x sqrt [R^3 / (G x M) ]

In the pg8 example, you've got a star with a mass of 3x10^30 kg, a gravitational constant of 6.674x10^-11, and a planetary orbital radius of 3.6x10^11 meters. Filling out the equation:

T = 2 x Pi x sqrt [3.6 x 10^11^3 / (6.674x10^-11 x 3x10^30) ]

Per the order of operations, taking care of the paranthetical terms first:

R^3 = (3.6 x 10^11)^3 = 4.6656x10^34
(G x M) = (6.674x10^-11 x 3x10^30) = 2.0022x10^20

And then divide those two, completing the work inside the parentheses:

[R^3 / (G x M) ] = [ 4.6656x10^34 / 2.0022x10^20] = 2.3302x10^14

Then you apply the square root:

sqrt [R^3 / (G x M) ] = sqrt (2.3302x10^14) = 15,265,133

Then you multiply by 2 and Pi:

T = 2 x Pi x sqrt [R^3 / (G x M) ] = 2 x Pi x 15,265,133 = 95,913,533 seconds

And to convert seconds to years:

95,913,533 / 31,536,000 = 3.04 years

How are you applying parentheses in your calculator? I've attached a picture on my TI-85 of how I set it up.

Was using a scientific calculator program for windows. Speed Crunch. Everything else seemed to work... lemme see if I can find what I entered..

2*3.14159*sqrt((3.6e11)^3/(6.674e11*3e30))  I think this is the first time in my life I have ever used scientific notation. Star is multiply by and it spits out 0.00095913452505037542.

Every other calculation I have had to do has worked...

cray

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Was using a scientific calculator program for windows. Speed Crunch. Everything else seemed to work... lemme see if I can find what I entered..

2*3.14159*sqrt((3.6e11)^3/(6.674e11*3e30))  I think this is the first time in my life I have ever used scientific notation. Star is multiply by and it spits out 0.00095913452505037542.

Every other calculation I have had to do has worked...

Got it! Thanks for spelling out your math. You dropped a sign on the highlighted number: it should be raised to the negative eleventh power (^-11), not positive 11. Slip a negative sign in there ahead of the 11 as follows:

2*3.14159*sqrt((3.6e11)^3/(6.674e-11*3e30))

The gravitational constant is a very small value, unlike the orbital radius and star's mass. When you do that, your result should change to about 95 million seconds.
Mike Miller, Materials Engineer

**"A man walks down the street in that hat, people know he's not afraid of anything." --Wash, Firefly.
**"Well, the first class name [for pocket WarShips]: 'Ship with delusions of grandeur that is going to evaporate 3.1 seconds after coming into NPPC range' tended to cause morale problems...." --Korzon77
**"Peace is that brief glorious moment in history when everybody stands around reloading." --Thomas Jefferson, or not

Disclaimer: Anything stated in this post is unofficial and non-canon unless directly quoted from a published book. Random internet musings of a BattleTech writer are not canon.