Time for some more research! Some of you might remember some curiosities about systems with G main stars: namely, that they are almost evenly split between mass codes C and D. This is in contrast to most other star types, and all others from the main sequence, where each main star type heavily favours one mass code. (See this thread.) So the question is, what differences there might be between system generation in one mass code and the other? After all, when I looked into main star ages, I saw that class G looks to be a mixture of classes F and K, see this post, or these pictures:
So this time around, I'd do a breakdown of both stars and ELWs in the different mass codes, to see what differences there might be.
First off, before we look at G main stars, what about all the G stars themselves? The compiled data on that is here, and let's see what that yielded. First off, some terminology there: "Single Star" means there's only the one G star in the system, and nothing else. "Main Star" means that the G star is the main star, and there are other stars too - so its identifier is [system name] A. "Secondary Star" is when it's something else: B, C, and so on.
With that in mind, the results are that first, single and main G stars are roughly the same amount across all mass codes. When it comes to secondary G stars though, there is a significant difference: there are quite few of these in code C, only 39,000 out of a 2.3 million total, while code D sees plenty of them, 0.83 million out of 3.1 million. G stars become much more rare in the higher mass codes, especially as single or main stars. Little wonder that in those, secondary G stars well outnumber the rest. (Still just around 75,000 of all kinds, across all mass codes.)
So if that's the picture of stars, how about ELWs? For this part, I looked at systems where the main star is G. There isn't much to say about ELWs in mass codes E-H, since there are only 48 of them, and 47 of those are in code E, with the one lone ELW in code H. C and D are where the interesting things might be. The numbers of ELWs around single G stars in mass code D is curiously lower than in C, although not by all that much. Meanwhile, when it comes to G main star systems with multiple stars, the combined total for both mass codes is the same, but D is slanted more towards ELWs being around secondary stars instead. (Both have the same amount of ELWs co-orbiting more than one star.) No big surprises here, of course: higher mass code systems have more mass to work with, so it makes sense if more and more luminous secondary stars would help ELWs. The more curious part is why the single G star scenario seems to favour mass code C over mass code D; however, the difference here is only to the tune of 10%, so I'm inclined to think that it could simply be down to some sort of scanning bias, and uncertainty.
What about the ELW characteristics? Data on those is here: mass code C and mass code D. The main star age histograms show the difference quite nicely, and the two kinds add up the interesting shape of the total charts (see above):
Pretty much the same distributions as earlier noted, just less smooth because of the much smaller sample size.
I was wondering if there would be any differences in the characteristics of the ELWs, between the two mass codes. Well, as it turns out, while things are mostly the same, there are still a few curious distinctions.
First, ELWs below 0.58 g surface gravity are almost entirely absent in mass code D, G main stars. Only a handful of them have been found. Take a look at these two charts:
Notice how mass code C has a tiny group on the left, which is missing from mass code D. These are the lightest gravity and thinnest atmosphere ELWs, and based on @Sapyx 's classification system from here, I like to call them Group 0. Note two more differences between mass codes C and D here: in D, Group 1 is less linear at the bottom, while in C, there are relatively more outliers around all four Groups. Bear in mind that the two sample sizes are quite similar: 25,973 ELWs in mass code C, G main star, and 24,489 ELWs in mass code D, G main star.
But then, looking at just the surface gravity histogram seems to favour higher gravities in mass code D better than in C.
Second, surface temperatures. I noticed something I haven't seen before here, namely that a histogram would show some teeth, spaced around 5 - 6 K between each:
Quite curious. Then there's the difference that even among G main stars, mass code C sees ELW temperatures fall more sharply than D does, so it favours the colder Earth-likes. But this difference is again most likely due to mass code D having more and/or more luminous secondary stars, which in turn help heat ELWs more.
Well, that's about all that comes to my mind. The ELW data is included above though, so maybe someone will see something else in there that I missed. (And all of the data sources I used are public anyway.) In my opinion, it's quite interesting to see how just the system mass can lead to differences in systems with G main stars, and how that influences ELW distributions too. Granted, most of that likely comes down to the fact that a higher system mass can also mean more luminous secondary stars in the system, which might also "railroad" Earth-likes into more distinct categories.
In terms of searching for Earth-likes though, none of this has any new insight, the same methods still apply as before.
And after all this, thanks for reading!
Also, the credits: thanks go to EDSM and EDDN for the crowdsourced data, and @Orvidius 's EDAstro for the processed sheets, which as usual saved me heaps of work from having to process the raw dumps for extra information myself.
So this time around, I'd do a breakdown of both stars and ELWs in the different mass codes, to see what differences there might be.
First off, before we look at G main stars, what about all the G stars themselves? The compiled data on that is here, and let's see what that yielded. First off, some terminology there: "Single Star" means there's only the one G star in the system, and nothing else. "Main Star" means that the G star is the main star, and there are other stars too - so its identifier is [system name] A. "Secondary Star" is when it's something else: B, C, and so on.
With that in mind, the results are that first, single and main G stars are roughly the same amount across all mass codes. When it comes to secondary G stars though, there is a significant difference: there are quite few of these in code C, only 39,000 out of a 2.3 million total, while code D sees plenty of them, 0.83 million out of 3.1 million. G stars become much more rare in the higher mass codes, especially as single or main stars. Little wonder that in those, secondary G stars well outnumber the rest. (Still just around 75,000 of all kinds, across all mass codes.)
So if that's the picture of stars, how about ELWs? For this part, I looked at systems where the main star is G. There isn't much to say about ELWs in mass codes E-H, since there are only 48 of them, and 47 of those are in code E, with the one lone ELW in code H. C and D are where the interesting things might be. The numbers of ELWs around single G stars in mass code D is curiously lower than in C, although not by all that much. Meanwhile, when it comes to G main star systems with multiple stars, the combined total for both mass codes is the same, but D is slanted more towards ELWs being around secondary stars instead. (Both have the same amount of ELWs co-orbiting more than one star.) No big surprises here, of course: higher mass code systems have more mass to work with, so it makes sense if more and more luminous secondary stars would help ELWs. The more curious part is why the single G star scenario seems to favour mass code C over mass code D; however, the difference here is only to the tune of 10%, so I'm inclined to think that it could simply be down to some sort of scanning bias, and uncertainty.
What about the ELW characteristics? Data on those is here: mass code C and mass code D. The main star age histograms show the difference quite nicely, and the two kinds add up the interesting shape of the total charts (see above):
Pretty much the same distributions as earlier noted, just less smooth because of the much smaller sample size.
I was wondering if there would be any differences in the characteristics of the ELWs, between the two mass codes. Well, as it turns out, while things are mostly the same, there are still a few curious distinctions.
First, ELWs below 0.58 g surface gravity are almost entirely absent in mass code D, G main stars. Only a handful of them have been found. Take a look at these two charts:
Notice how mass code C has a tiny group on the left, which is missing from mass code D. These are the lightest gravity and thinnest atmosphere ELWs, and based on @Sapyx 's classification system from here, I like to call them Group 0. Note two more differences between mass codes C and D here: in D, Group 1 is less linear at the bottom, while in C, there are relatively more outliers around all four Groups. Bear in mind that the two sample sizes are quite similar: 25,973 ELWs in mass code C, G main star, and 24,489 ELWs in mass code D, G main star.
But then, looking at just the surface gravity histogram seems to favour higher gravities in mass code D better than in C.
Second, surface temperatures. I noticed something I haven't seen before here, namely that a histogram would show some teeth, spaced around 5 - 6 K between each:
Quite curious. Then there's the difference that even among G main stars, mass code C sees ELW temperatures fall more sharply than D does, so it favours the colder Earth-likes. But this difference is again most likely due to mass code D having more and/or more luminous secondary stars, which in turn help heat ELWs more.
Well, that's about all that comes to my mind. The ELW data is included above though, so maybe someone will see something else in there that I missed. (And all of the data sources I used are public anyway.) In my opinion, it's quite interesting to see how just the system mass can lead to differences in systems with G main stars, and how that influences ELW distributions too. Granted, most of that likely comes down to the fact that a higher system mass can also mean more luminous secondary stars in the system, which might also "railroad" Earth-likes into more distinct categories.
In terms of searching for Earth-likes though, none of this has any new insight, the same methods still apply as before.
And after all this, thanks for reading!
Also, the credits: thanks go to EDSM and EDDN for the crowdsourced data, and @Orvidius 's EDAstro for the processed sheets, which as usual saved me heaps of work from having to process the raw dumps for extra information myself.