R-T-B Posted December 25, 2024 Author Share Posted December 25, 2024 On 12/23/2024 at 6:07 PM, Professor K said: Just to satisfy my curiosity, what is the formula for calculating the mass from the radius and GeeASL? 23 hours ago, OhioBob said: Yes, but not exactly. For that formula to work, gravity must be in m/s2, not gees. So you have to multiply geeASL by 9.80665 to convert. Thanks OhioBob, I was about to point him to you but you had already replied, lol. Quote Link to comment Share on other sites More sharing options...
OhioBob Posted December 25, 2024 Share Posted December 25, 2024 (edited) 18 hours ago, Professor K said: I was just coming to post that the Google formula did not quite provide results that matched the stock planets, but your update fixed that. With the shift to G in m/s the formula produces very close to stock results. I have my formula! : ) Thank you! -K Body Wiki Mass Calculated Mass GeeASL Radius G in m/s Moho 2.5263314000E+21 2.5255594512E+21 0.275 250000 2.69682875 Eve 1.2243980000E+23 1.2240238678E+23 1.700 700000 16.67130500 Gilly 1.2420363000E+17 1.2416568647E+17 0.005 13000 0.04903325 Kerbin 5.2915158000E+22 5.2898990686E+22 1.000 600000 9.80665000 Mun 9.7599066000E+20 9.7569249488E+20 0.166 200000 1.62790390 Minmus 2.6457580000E+19 2.6449495343E+19 0.050 60000 0.49033250 Duna 4.5154270000E+21 4.5140472052E+21 0.300 320000 2.94199500 Ike 2.7821615000E+20 2.7813113770E+20 0.112 130000 1.09834480 Dres 3.2190937000E+20 3.2181100984E+20 0.115 138000 1.12776475 Jool 4.2330000000E+24 4.2319192549E+24 0.800 6000000 7.84532000 Laythe 2.9397311000E+22 2.9388328159E+22 0.800 500000 7.84532000 Vall 3.1087655000E+21 3.1078157028E+21 0.235 300000 2.30456275 Tylo 4.2332127000E+22 4.2319192549E+22 0.800 600000 7.84532000 Bop 3.7261090000E+19 3.7249705941E+19 0.060 65000 0.58839900 Pol 1.0813507000E+19 1.0810202630E+19 0.038 44000 0.37265270 Eeloo 1.1149224000E+21 1.1145817338E+21 0.172 210000 1.68674380 There are a couple reasons for the small differences. First, those aren't the correct geeASL values. The actual values are weird fractions. For example, Moho's geeASL is actually 0.27509394... not 0.275. The reason for this is because years ago Squad changed the value of 1 standard gee from 9.81 (which was used in the beta versions) to 9.80665 m/s2. Because of this they mulitplied all the original geeASL values by 9.81/9.80665. You're using the original pre-converted geeASL values, so to account for this you either have to change all those to the current numbers, or (much easier) just mulitple the values you have by 9.81 instead of 9.80665. The second thing is the value of the gravitational constant used in KSP is 6.67408E-11 (looks like you're using 6.67384E-11). If you make these two changes you should be exact. Edited December 25, 2024 by OhioBob Quote Link to comment Share on other sites More sharing options...
Professor K Posted December 26, 2024 Share Posted December 26, 2024 8 hours ago, OhioBob said: There are a couple reasons for the small differences. First, those aren't the correct geeASL values. The actual values are weird fractions. For example, Moho's geeASL is actually 0.27509394... not 0.275. The reason for this is because years ago Squad changed the value of 1 standard gee from 9.81 (which was used in the beta versions) to 9.80665 m/s2. Because of this they multiplied all the original geeASL values by 9.81/9.80665. You're using the original pre-converted geeASL values, so to account for this you either have to change all those to the current numbers, or (much easier) just multiply the values you have by 9.81 instead of 9.80665. The second thing is the value of the gravitational constant used in KSP is 6.67408E-11 (looks like you're using 6.67384E-11). If you make these two changes you should be exact. Thank you! I got the geeASL numbers from a chart on the KSP Wiki, but I have noticed that a lot of numbers there appear to have been truncated so it doesn't surprise me. And the GC I had gotten from the KOS online documentation and a couple of forum and Reddit posts. I'm not actually doing anything with the stock planets, I just used them to test the formula against bodies I had the mass for to verify it was working but I'll definitely update my formula/patches with the correct GC. Is there an online source for the more precises geeASL numbers? -K Quote Link to comment Share on other sites More sharing options...
OhioBob Posted December 26, 2024 Share Posted December 26, 2024 19 hours ago, Professor K said: Is there an online source for the more precises geeASL numbers? You can get all that information from here: kittopia-dumps/Configs at master · Kopernicus/kittopia-dumps · GitHub The actual geeASL numbers should be the geeASL numbers from your table times 9.81/9.80665. From the Kittopis dumps, this works out to be exact for Kerbin (geeASL = 1.00034160493135). But for the other bodies there's a slight error and I don't know why. For instance, for Moho the Kittopia dump gives the value, geeASL = 0.275093947318621 But the computed value is, geeASL = 0.275 * 9.81/9.80665 = 0.275093941356121 I can't explain the difference, but being off only only 6 parts in a billion I think is close enough. Quote Link to comment Share on other sites More sharing options...
R-T-B Posted December 29, 2024 Author Share Posted December 29, 2024 New in this latest version release-220: 1.) A small hotfix for the light intensity on setting "KSCLightsAlwaysOn." previously they were only roughly "50% on" in brightness, now they are fully on. See Known Bugs & Caveats for known bugs. Quote Link to comment Share on other sites More sharing options...
DareMightyThingsJPL Posted January 6 Share Posted January 6 Hello! I have a curiosity about the lack of comets in the Kopernicus Asteriod Generator (you have to change to the stock generator in the Kopernicus_Config.cfg). What's the reason comets only work with the stock generator? Thanks in advance Quote Link to comment Share on other sites More sharing options...
Professor K Posted Friday at 01:47 PM Share Posted Friday at 01:47 PM Is there a PQS mod that can generate a polyhedral shaped planet? I was thinking it might be possible with a properly done heightmap, but I'm not sure how sharp an edge you could get that way. -K Quote Link to comment Share on other sites More sharing options...
R-T-B Posted 14 hours ago Author Share Posted 14 hours ago (edited) On 1/6/2025 at 3:15 PM, DareMightyThingsJPL said: Hello! I have a curiosity about the lack of comets in the Kopernicus Asteriod Generator (you have to change to the stock generator in the Kopernicus_Config.cfg). What's the reason comets only work with the stock generator? Thanks in advance Honestly? Laziness. I tried years ago to add comets to the Kopernicus Generator and it beat me up so now I am afraid/too lazy to try again. I'm actually considering trying again this February, so stand by and see if I get brave enough, lol. On 1/10/2025 at 5:47 AM, Professor K said: Is there a PQS mod that can generate a polyhedral shaped planet? I was thinking it might be possible with a properly done heightmap, but I'm not sure how sharp an edge you could get that way. -K Not that I know of... but people have done some crazy things by importing premade models as cache files. Not entirely sure of the specifics there. Edited 14 hours ago by R-T-B Quote Link to comment Share on other sites More sharing options...
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