Elite Observatory - Search your journal for potentially interesting objects, or notify you of new ones on the fly while exploring!

Baxder

Baxder
OK, I've collected data for 25 of each GG type when I had them. I only have 24 Class IV's, eight Water Giants and six Class V's in my logs with Rotation Periods under .8 days. Here's what I find:

1) The formula of RP*G remains the best method I can derive for determining squishiness, but there is likely a better way. With the R*PG method, the major cutoff points remain .5 and 1.6. 16 of 25 "Extreme" squishies are at or below .5. (Four more fall between .6 and .65. However, their concentration is lessened and .57 is where the "None" bodies begin to creep in). There is only one squishy world out of the 95 above 1.6, which I'll come to below.

2) In what is surely my still limited sample, most squishies are Class I, II, WBL or ABL. This fits with everyone's theories of squishiness being determined primarily by Body Gravity vs. Rotation Period. None of the Water Giants with RP's under .8d in my journals were squishy, but there are only eight of them, and they all fell above the RP*G threshold of 1.6. My sample is likely too small to determine the actual rarity of squishies for any class, but hopefully, this research will aid in doing so.

3) 17 non-squishy bodies fall below the RP*G threshold, ranging from .57 to 1.56. At some point, I noted that in cases of squishiness with relatively high gravity, the Body Radius was always high. This makes sense, given that the further the planet's surface is from its core, the less it is affected by the planet's gravity, making it more susceptible to the centrifugal forces that make them squishy. Non-squishy bodies below the R*PG 1.6 threshold should, therefore, have smaller radii to gravity ratios and lower RP's. Sorting the spreadsheet by Gravity > Radius clearly shows this is the case with these bodies. All of the non-squishies below the threshold that have the same gravity as squishies have the smallest Radii and/or slowest Rotation Periods.

846QtM0.jpg


4) I did come across one Class III world with 2195 EM, 73 Mm Radius, 166 Gravity and a .15 RP (3.6 hours) that was moderately squishy. It's R*PG value was 24.9. There are plenty of .2 RP worlds with a fraction of that gravity and radius that are not squishy, and I have no explanation, except that that gravity number must be a glitch in my journal. See, it was the only Class III squishy I came across but was "Unexplored" in the SysMap (a frustratingly common occurrence, since G and RP are two of the stats missing from "unexplored" bodies, but it's apparently in the journal, so it shows up in Observatory! Not a critique; I get that this is an unforeseen use of the app.) so I had to data mine my journal for it's stats. It's body 2 in LTT 10410, in the bubble, if anyone wants to check it out and let me know what's up.

xlJBHid.png


Conclusion:
There is a deeper math and a better method of determining squishiness here that has eluded me thus far. I have attempted various formulas with G/R/EM ratios and RP that have not been successful in sorting the non-squishies; the RP/G method I mentioned previously is now bust. I will be seeking help from anywhere I can with this problem, and it would be awesome if someone here could take up the math as well. I for one will use the R*PG method and take the odds until someone does.

docs.google.com

Oblated Gas Giants

docs.google.com docs.google.com

I'm sure it'll be quiet around here for the rest of the week/year, so merry merry and happy happy, everyone!
 
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Baxder

Baxder
Baxder said:
Edited to reflect post below, removing RP/G criteria.

XML: 
<Criteria Comparator="And">
    <Criteria Comparator="Equal" Value="1">
        <Operation Operator="None">
            <FirstValue Type="EventData">PlanetClass:gas giant with ammonia based life</FirstValue>   
        </Operation>
    </Criteria>
    <Criteria Comparator="Between" LowerValue="-140000" UpperValue="140000">
        <Operation Operator="Multiply">
            <FirstValue Type="EventData">SurfaceGravity</FirstValue>
            <SecondValue Type="EventData">RotationPeriod</SecondValue>
        </Operation>
    </Criteria>
    <Description>Ammonia Life Squishy</Description>
    <Detail>
        <Item>DistanceFromArrivalLS</Item>
    </Detail>
</Criteria>
Click to expand...

This isn't working and I can't figure out why. The numbers should be good, so I'm assuming there's something wrong in the "between" comparator. All I did was paste that specific comparator into my XML file, replacing the "less than .8d (in seconds) comparator," which worked before I pasted this "between" comparator in. Now I get no results for squishies.
 

Zieman

Zieman
Baxder said:
This isn't working and I can't figure out why. The numbers should be good, so I'm assuming there's something wrong in the "between" comparator. All I did was paste that specific comparator into my XML file, replacing the "less than .8d (in seconds) comparator," which worked before I pasted this "between" comparator in. Now I get no results for squishies.
Click to expand...
SurfaceGravity in the Journals is in m/s², and values in System Map use the rough approximation of g as 9.8 m/s², so adding a zero to the "between" values should do the trick.
If you want to stick closer to the ±0.8d*1.6g limit(s), 1355000 is closer to the mark.
(24*60*60*0.8*1.6*9.8 = 1354752)
 
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Baxder

Baxder
Zieman said:
SurfaceGravity in the Journals is in m/s², and values in System Map use the rough approximation of g as 9.8 m/s², so adding a zero to the "between" values should do the trick.
If you want to stick closer to the ±0.8d*1.6g limit(s), 1355000 is closer to the mark.
(24*60*60*0.8*1.6*9.8 = 1354752)
Click to expand...
Got it, thanks. Perhaps there could be a "journal unit conversion" section of the custom criteria readme?
 

Vithigar

Vithigar
Holy cow, this thread has been hopping while I've been away. Christmas has been eating more of my time than expected (on top of being sick again), so I'm no longer sure I'll have an update before the new year, but it shouldn't be long after that.

As for the things that have been discussed while I've been away/busy...

Record Breakers
This is not a bad idea actually. Hand editing custom criteria to check for them is straightforward enough, but it's definitely a noteworthy enough find to consider making it "official". Updating the current records via an online source should not be difficult, it's just a matter of someone taking responsibility for maintaining it. Doing it dynamically via EDSM data might be possible too. I'll have to dig into it and see.

Shared Screenshots
Love 'em. @Baxder @Martin Shepard keep 'em coming.

Oblate Gas Giants
Nice idea. I don't have any inspiration as to how they might be found more reliably, but that's definitely something worth trying to narrow down. I might take a stab and see if I can figure anything out using the centrifugal force formula. Looks like you're getting close though.

Units of Measure
Agreed that it would be handy to have a reference for exactly what units are being used in the journals. I'll write one up.
 

Ashnak

Ashnak
Not sure that RP*G is a good criterium - it may be the best we can come up with right now (i.e. Baxder came up with, and nobody has found anything better yet), but I've come across this beauty:

ZzCJBGV.jpg

RP*G = 0.42, and no outstanding flattening.

--

Update: system map view - flattening visible:

nX2wmfI.jpg
 
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ShadowNUAR

ShadowNUAR
varonica said:
I've only ever come across that once when I sorted by one of the columns, otherwise it doesn't seem to happen to me at all. Did you by any chance sort the contents of the window for some purpose then go on exploring and gathering more listings?
Click to expand...
it is .... returned sorting by time and everything is OK
 

MattG

MattG
RE: Flattening, one formula to estimate the flattening coefficient (assuming uniform density and various other factors is:
O16Rb05.png


Where w is (2 * PI / rotation period), r is mean radius and M is body mass (seconds, meters and kg). Oh, and G is the gravitational constant. This factor (f) can then be used to calculate the equatorial radius and polar radius as this:
FR6E8i4.png


Finally, you can compare this difference between the radii as a ratio of the equatorial radius. I've put this into a copy of the spreadsheet pasted earlier and sorted on this ratio. Results are promising:
Oblated Gas Giants

I'd say if you considered everything with a ratio of under 12, it'd be pretty close (or perhaps 10). Only 2 of the extreme ones are missed, and there's likely something else going on there (I think close binary orbits affect things, for example). Worth pointing out that the spreadsheet is (mostly) not journal data - journal data would help accuracy of calculations. I expect this would be quite a challenge to put in custom XML though, perhaps it's something Vithigar can build in (or maybe I could).
 

Baxder

Baxder
MattG said:
RE: Flattening, one formula to estimate the flattening coefficient (assuming uniform density and various other factors is:
O16Rb05.png


Where w is (2 * PI / rotation period), r is mean radius and M is body mass (seconds, meters and kg). Oh, and G is the gravitational constant. This factor (f) can then be used to calculate the equatorial radius and polar radius as this:
FR6E8i4.png


Finally, you can compare this difference between the radii as a ratio of the equatorial radius. I've put this into a copy of the spreadsheet pasted earlier and sorted on this ratio. Results are promising:
Oblated Gas Giants

I'd say if you considered everything with a ratio of under 12, it'd be pretty close (or perhaps 10). Only 2 of the extreme ones are missed, and there's likely something else going on there (I think close binary orbits affect things, for example). Worth pointing out that the spreadsheet is (mostly) not journal data - journal data would help accuracy of calculations. I expect this would be quite a challenge to put in custom XML though, perhaps it's something Vithigar can build in (or maybe I could).
Click to expand...

giphy.gif


Seriously, you're my hero. Exact measurements would be great, but I didn't use exact numbers because we aren't making exact measurements of any given planet's distortion (or we weren't until now); it's just a visual judgment call, and I didn't take the time to scour my journal for each planet's data when I already had to visit each one in its system map and make that call. I think a rough cut-off should suffice just fine. I'd make it high to start, maybe even as high as 15, and decrease it until you stop getting false positives, then put it back up to have a tolerable cushion.

Edited for tone
 
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