OhioBob

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About OhioBob

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  1. As long as the planet is big enough and has the right temperature to retain the gas to begin with, it should be able to hold onto it indefinitely. If a gas is lighter than the "minimum molecular weight retained", it will eventually leak away into space and be lost. And of course there are some gases that are removed by natural processes and need constant replenishment by other processes. If the process that supplies the gas stops, the gas will eventually be removed from the atmosphere. Solar wind will also strip away an atmosphere, particularly if the planet has no magnetic field. There's no easy answer. You're just going to have to make an educated guess.
  2. @Pretorian28715, although I haven't officially released a formula to compute surface pressure, there is a method I sometimes use as a rough guideline to help me determine the surface pressure of one planet versus another. If you use my atmosphere spreadsheet, there is a number given in cell M33 titled "Minimum molecular weight retained." The lower that number, the more effective the planet is at retaining an atmosphere. Also important in determining the surface pressure is the surface gravity. If the atmospheres of two bodies have the same mass per unit area, the one with the greater surface gravity will have the higher surface pressure (where surface pressure is weight per unit area). So what I end up doing it taking the planet's surface gravity and dividing it by the minimum molecular weight retained. This gives a parameter that can be used to estimate roughly the ratio of one planet's surface pressure to another (assuming the planets evolved similarly). The surface pressures can still vary considerably, but at least this gives us something to start with so we're not just making wild guesses. (edit 1) If forced to write a formula, I'd use P = 5 * g / M where P is surface pressure in atmospheres, g is surface gravity is standard gravities, and M is minimum molecular weight retained in g/mole. The constant 5 is used so that when the formula is applied to Earth we get a surface pressure of about 1 atmosphere. Let me remind you that this is only a very rough estimation. Wild variation is possible. (edit 2) For gas giants, I just use a standard value for the datum level pressure. For stock sized planets I typically use 15 atmospheres, only because that's the pressure at Jool's datum. For RSS we used a pressure of 1000 atm. Whatever value you decide to use, I recommend you use the same for all gas giants.
  3. For making an atmosphere, I recommend you use the tools I've developed for this, which @Galileo just linked too. To answer your specific question, no, I have not been able to derive any particular formula to determine how much atmosphere a planet should have. There is a formula to determine what gases a planet should be able to retain based on size and temperature (included in my spreadsheet), but not what a planet's surface pressure should be. Just look at our own solar system. We have Earth and Venus very similar in size, yet Venus has nearly 100 times the surface pressure. And then we have a small body like Titan that has nearly 1.5 times Earth surface pressure. (And considering Titan's low surface gravity, the mass of the atmosphere per unit area is about 10 times Earth.) And then we have other bodies with extremely thin atmospheres. There is just so much extreme variability that coming with a formula has proven impossible. For most other parts of the atmosphere modeling process I've been able to come up with formulas to at least make some suggestions, but deciding what surface pressure to give your planet is still entirely up to you. Generally speaking, I think the larger and colder a planet is, the more likely it is to have a think atmosphere. But other than that, I don't have much advice.
  4. Other than the PQSMods thing, I don't see anything obvious. There are some things you could have added but didn't, like timewarpAltitudeLimits for example. When you don't specify something like that, you'll get the values of the template. I presume you'll eventually add biomes and an atmosphere?
  5. You didn't mention the textures. Did you download and install them? There are two downloads, GPP and GPP_Textures. After installing GPP into your GameData folder, you must copy GPP_Textures into your GPP folder.
  6. That's the old fix for version 1.2.2 (if you do that in version 1.2.3, it will break things). The new fix is much better. I won't bore you with details, but you should now get the correct solar panel power output at both Ciro and Grannus. However, the fix only works with the Kopernicus bundled in the GPP download. You must use the bundled Kopernicus, do not download it separately.
  7. There have been some ongoing issues with solar panel power output. In this thread we've suggested some fixes meant to remedy these problems. If you were playing without all the fixes, then it's possible you were getting a power output way greater than it should have been (about 32 times greater). GPP version 1.2.3, if installed correctly, incorporates all the fixes and should give you the correct power output. This is likely why you are seeing a reduction from your previous installation. What you are getting now should be correct. If you put a 3x2 or 1x6 solar panel in orbit around Gael, you should get a power output of about 1.64.
  8. Now that I've had some time to think about it, no, we can't do that. The chargeRate factor applies to all solar panels everywhere. We can't lower the chargeRate at Grannus below the ratio of its luminosity to Ciro's luminosity. The only way to decrease the chargeRate at Grannus is to artificially lower its luminosity. And if we lower the luminosity, we lower heating rates below where they should be. So there's no way to have both a reduced chargeRate and correct heating rates at the same time. Best just to keep the luminosities where they are.
  9. I think MaxL_1023 is saying that the solar panel power output should be even less than luminosities imply because Grannus radiates much of it light in a part of the spectrum where solar panels do not work efficiently. So while Grannus has 3% of Ciro's luminosity, solar panels might produce only 1-2% (or whatever the right number is).
  10. We could, but it might confuse people who don't know that. We'll discuss it and decide.
  11. @TheRagingIrishman, you're awesome man! That's perfect. Thank you so much.
  12. I don't know if the multiple star/luminosity/solar panel problem is something in Kopernicus or something in KSP itself. Either way, it's frustrating. I recently exchanged PMs with one of the KSP devs and gave him a wish list of fixes. One of these was the multiple star problem. I was told that they'd discuss it and possibly put it on their bug tracker. I have no idea if anything will ever become of it.
  13. The presumption is that Kerbal and human technology have developed along a similar timeline. My article is written assuming a 1950s level of technology. Adaptive optics didn't become practical until the 1990s.
  14. I doubt I'll ever get around to making a book because my priorities are elsewhere at the moment. I just don't see the motivation to do so returning. When I did consider making a book, I was planning to simply make it a PDF that could be downloaded for free. Although a hardcover coffee table book would be terrific, I've never considering absorbing the expense to do such a thing.
  15. Here's another spreadsheet that I've made to supplement the first: temperatureCurve and temperatureSunMultCurve calculator It produces temperature curves that can be copied and pasted into the spreadsheet KSPatmospheres.xlsx. Curves can be produced for four types of atmospheres: Star, Gas Giant, Earthlike, and Other. The curves are only a suggestion, you are of course free to use whatever you like. Most of the data entered into this spreadsheet is as described in the previously provided instructions. The two spreadsheets are made to be used together, so whatever properties you enter into one should be duplicated in the other. This spreadsheet also provides some suggested properties. For stars, the suggested radius and surface gravity are computed on the basis of luminosity, presuming a main sequence star. The suggested surface gravity for other bodies is based on real life bodies of similar type found in our own solar system. While you are certainly under no obligation to use the suggestion, deviating from it too far may result in a body having an unrealistic density. The suggested greenhouse effect it little more than a guesstimate, using an empirical formula based on a very small sample size. The actual greenhouse effect could vary considerably. For "other" atmospheres it is necessary to estimate the body's mean surface elevation (cell R20), which is required to compute the temperature at the datum. If your body is a moon orbiting in the strong magnetosphere of a gas giant, then select "Y" (yes) in cell R21, else "N" (no). The presence of a strong magnetosphere increases the exospheric temperature. These curves likely extend well beyond what is required. It is recommended that you trim off the unneeded elevations when finalizing the atmospheric model. For this spreadsheet to work, interation must be enabled.