I'm just curious.... have there been any other systems found that are nearly identical (same number of bodies, same configuration of bodies, same star type, etc) to Sol?
Does Sol have a twin?
- Thread starter Wardefined
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You'll have to define exactly how close the planets can be to their Sol-analogues.
Does Venus have to be hot thick CO2 atmosphere?
Does Earth need to be Earth-sized and have matching Earth parameters, or will any old "Earth-like" or Water world do?
Do you want to match 2021-Sol, or 3307-Sol? The difference is planet 4, which in 3307-Sol is a second Earth-like (terraformed Mars).
Does there need to be an asteroid belt between planets 4 and 5?
Do the moon counts for the gas giants need to match?
Do you need to include all the dwarf planets, or can you stop at Neptune?
A match for Sol is going to be very, very hard for the Stellar Forge to generate. The game doesn't really like generating Sol-type star systems, with a mixture of gas giants and terrestrials - most systems are all one or all the other.
Does Venus have to be hot thick CO2 atmosphere?
Does Earth need to be Earth-sized and have matching Earth parameters, or will any old "Earth-like" or Water world do?
Do you want to match 2021-Sol, or 3307-Sol? The difference is planet 4, which in 3307-Sol is a second Earth-like (terraformed Mars).
Does there need to be an asteroid belt between planets 4 and 5?
Do the moon counts for the gas giants need to match?
Do you need to include all the dwarf planets, or can you stop at Neptune?
A match for Sol is going to be very, very hard for the Stellar Forge to generate. The game doesn't really like generating Sol-type star systems, with a mixture of gas giants and terrestrials - most systems are all one or all the other.
Let's crunch some numbers, to see how improbable a twin is.
I'll be using Marx' database of ELWs, mainly because it's a relatively small list, at only 20331 ELWs, plus it also has screenshots of the system map, to show how the system as a whole looks.
The number of these 20331 systems that have a G type star as the primary star: 3453.
The number where that G type star is the only star in the star system (i.e no binary stars or brown dwarfs): 1629
The number of those sole-G ELW systems where the ELW is in planet position number 3: 285
The number of those systems where the ELW in question also has a single moon and no rings: 42
The number of these 42 systems that have any gas giants in the system at all: 3.
Yep, just 3.
Of these three systems, only one of them has more than one gas giant. So, behold, I give you the star system in Marx's ELW database that is "most like Sol": the Swoilz FS-H D11-70 system:
As you can see, not really all that "Sol-like". The asteroid belt is in the wrong place, Pseudo-Mercury is bigger than pseudo-Venus and pseudo-Earth, pseudo-Venus has a moon, pseudo-Mars is completely missing, and the system stops at pseudo-Saturn. And pseudo-Earth itself barely qualifies as "Earth-like": a high-gravity, hot and steamy jungle planet with an average surface temperature that's 47 degrees Celsius - or 32 deg C hotter than Earth's average. But it's still the best match for Sol that the ELW-hunting community has found and published here on the forums.
Here are the other two runners-up:
Prie Chruia MR-W D1-6 at Source: https://www.flickr.com/photos/132207737@N08/34667927372
...and Pheia Ain OM-W D1-48:
I'll be using Marx' database of ELWs, mainly because it's a relatively small list, at only 20331 ELWs, plus it also has screenshots of the system map, to show how the system as a whole looks.
The number of these 20331 systems that have a G type star as the primary star: 3453.
The number where that G type star is the only star in the star system (i.e no binary stars or brown dwarfs): 1629
The number of those sole-G ELW systems where the ELW is in planet position number 3: 285
The number of those systems where the ELW in question also has a single moon and no rings: 42
The number of these 42 systems that have any gas giants in the system at all: 3.
Yep, just 3.
Of these three systems, only one of them has more than one gas giant. So, behold, I give you the star system in Marx's ELW database that is "most like Sol": the Swoilz FS-H D11-70 system:
As you can see, not really all that "Sol-like". The asteroid belt is in the wrong place, Pseudo-Mercury is bigger than pseudo-Venus and pseudo-Earth, pseudo-Venus has a moon, pseudo-Mars is completely missing, and the system stops at pseudo-Saturn. And pseudo-Earth itself barely qualifies as "Earth-like": a high-gravity, hot and steamy jungle planet with an average surface temperature that's 47 degrees Celsius - or 32 deg C hotter than Earth's average. But it's still the best match for Sol that the ELW-hunting community has found and published here on the forums.
Here are the other two runners-up:
Prie Chruia MR-W D1-6 at Source: https://www.flickr.com/photos/132207737@N08/34667927372
...and Pheia Ain OM-W D1-48:
@Sapyx thank you for the incredibly well thought out and detailed answer. That is exactly what I was looking for, essentially "how likely is it that the Stellar Forge would generate a system nearly identical to our own?" If this were Mythbusters, I'd summarize the results as "Plausible", but definitely unlikely to come close enough to be a twin.
Under the assumption that only 0.05% or whatever of the galaxy is explored and already 3 are found which aren't that far from a twin, I'd say it's very plausible 
Out in the black with you and find it
Out in the black with you and find it
The old FE2/FFE procedural star system generator tended to make much more "Sol-like" star systems. It was written back in the early 1990s, before any extrasolar planets were detected, so the only star system we actually knew anything about was Sol. Back then we assumed (using the Copernican Principle) that Sol must be a "normal" star system, so our theories of planetary system generation were skewed towards making star systems that looked like our own. So the generator was programmed to generate star systems that looked not too different from Sol.
We now have a quite extensive real-world database of extrasolar planets, and even quite a few "star systems" with multiple known planets. From this extended set of observations, we now believe that Sol is abnormal and indeed rather odd in its mixture of planet sizes; it's far more "normal" for a star to have a set of planets that are all much the same size. This observation has been carried into the Stellar Forge algorithms, with the result that ED's star systems very often are just a string of lookalike planets - whether that's a string of iceballs, or gas giants, or HMCs.
But this does mean that it's far more likely for there to be a better "twin of Sol" amongst the small number of hand-crafted systems that were copied across from FE2 into ED, rather than out in the bulk of the procedurally-generated galaxy. Marx's database doesn't include these star systems, as they are usually inhabited and the database only looks at uninhabited systems.
Delta Pavonis, Beta Hydri and Anlave are three examples of G type star systems copied over from FE2 into ED. Apart from the lack of moons, Delta Pavonis is just as good if not better than our leading Stellar Forge procedurally-generated candidate:
...and in the other two systems, the ELW's planet number is higher than 3, but the systems are nevertheless more Sol-like in structure than a typical ED procedurally-generated system:
We now have a quite extensive real-world database of extrasolar planets, and even quite a few "star systems" with multiple known planets. From this extended set of observations, we now believe that Sol is abnormal and indeed rather odd in its mixture of planet sizes; it's far more "normal" for a star to have a set of planets that are all much the same size. This observation has been carried into the Stellar Forge algorithms, with the result that ED's star systems very often are just a string of lookalike planets - whether that's a string of iceballs, or gas giants, or HMCs.
But this does mean that it's far more likely for there to be a better "twin of Sol" amongst the small number of hand-crafted systems that were copied across from FE2 into ED, rather than out in the bulk of the procedurally-generated galaxy. Marx's database doesn't include these star systems, as they are usually inhabited and the database only looks at uninhabited systems.
Delta Pavonis, Beta Hydri and Anlave are three examples of G type star systems copied over from FE2 into ED. Apart from the lack of moons, Delta Pavonis is just as good if not better than our leading Stellar Forge procedurally-generated candidate:
...and in the other two systems, the ELW's planet number is higher than 3, but the systems are nevertheless more Sol-like in structure than a typical ED procedurally-generated system:
I would totally love one of these systems to become inhabited and called Sol 2, lol. Like maybe someone wants to feel somewhat at home, but hates the Feds or something.Let's crunch some numbers, to see how improbable a twin is.
I'll be using Marx' database of ELWs, mainly because it's a relatively small list, at only 20331 ELWs, plus it also has screenshots of the system map, to show how the system as a whole looks.
The number of these 20331 systems that have a G type star as the primary star: 3453.
The number where that G type star is the only star in the star system (i.e no binary stars or brown dwarfs): 1629
The number of those sole-G ELW systems where the ELW is in planet position number 3: 285
The number of those systems where the ELW in question also has a single moon and no rings: 42
The number of these 42 systems that have any gas giants in the system at all: 3.
Yep, just 3.
Of these three systems, only one of them has more than one gas giant. So, behold, I give you the star system in Marx's ELW database that is "most like Sol": the Swoilz FS-H D11-70 system:
As you can see, not really all that "Sol-like". The asteroid belt is in the wrong place, Pseudo-Mercury is bigger than pseudo-Venus and pseudo-Earth, pseudo-Venus has a moon, pseudo-Mars is completely missing, and the system stops at pseudo-Saturn. And pseudo-Earth itself barely qualifies as "Earth-like": a high-gravity, hot and steamy jungle planet with an average surface temperature that's 47 degrees Celsius - or 32 deg C hotter than Earth's average. But it's still the best match for Sol that the ELW-hunting community has found and published here on the forums.
Here are the other two runners-up:
Prie Chruia MR-W D1-6 at Source: https://www.flickr.com/photos/132207737@N08/34667927372
...and Pheia Ain OM-W D1-48:
I doubt FDev would go to all that trouble, and then hide it somewhere out there in the 400 billion stars. If they'd done something like that and put it too far away or not in a direct line to the Core, it's likely no-one would ever find it without hints.
Hey @Orvidius , any chance of getting a search of your EDSM mega-database that matches my parameters? (G-type primary, no other stars, ELW in position 3, with a moon and no rings). I'd guess about 30 hits; verifying gas giants and the appearance of the system maps in those systems might make a good list of targets for my next exploration voyage.Raxxla, maybe?
Hmmm... a very Sol-like system... I may need to add that to my bucket list of things to find.
That might work, I'll see what I can do.
I studied Astronomy at university. What we determined was if you re ran the universe it would look different. Especially the Solar system which was a bit random. In Elite it had to be 'designed' it wasnt generated by stellar forge. We also think Evolution rerun would also produce different looking animals/humans .. or none. Jupiter could be considered a failed Star..
OK, check this out. 68 of them, and that's with requiring at least one gas giant.
https://edastro.com/mapcharts/files/sol-like-systems.csv
Awesome and many thanks, you got a "known Gas Giant counter" in there too!
Of course, if it's "old data" (pre-FSS) or from a cherry-picker, it's entirely likely that the gas giant counts are wrong, which is why I didn't mention it in main parameters. But we've got it and we can work with it.On this new list, there's one - yes, just one - with four gas giants. I'd hoped this may be the "most Sol-like" system so far. But alas, there's a fatal flaw with this star system: according to EDSM, Planet 1 is one of those four gas giants, a Hot Jupiter. The "Hot Jupiter + ELW" configuration is so rare, I didn't think it would be a likely complication, but I notice that in the three runner-up systems, a Hot Jupiter features in two of them.
Stellar Forge must really, really hate spitting out Sol-twins.
Which leaves the last remaining three-gas-giant system, Hypou Aoscs DP-X c15-1798, as our best known Sol-match to date. On EDSM it doesn't look too bad: Mercury and Venus are a bit too small and close to the sun, Mars is missing again and (as usual) the asteroid belt is in the wrong place, and of course there's a fourth gas giant that's missing, but otherwise it looks good on paper. It's in the Core so would take me a while to get there to check the system map appearance; I certainly couldn't make it there and back again before Odyssey lands.
That's actually a really good point about cherry picking, particularly in the pre-FSS era. I've regenerated the spreadsheet without the gas giant requirement, so that we can at least see the additional cases. That brings it up to over 600 candidates.... yikes!
Edit: Maybe I should have it filter out cases where the data shows a gas giant as one of the innermost planets, and add a total body count column as well.
Edit: Maybe I should have it filter out cases where the data shows a gas giant as one of the innermost planets, and add a total body count column as well.
OK, I added a filter for this, and it only eliminated around 3 of them, so it's still showing 606 candidates.
So of those 600+ systems, the only Hot-Jupiter-with-ELW-in-position-3 systems it found were the three we've already noted in this thread? I thought Hot Jupiter + ELW was rare.
And I've found another issue with Hypou Aoscs DP-X c15-1798: two of the three gas giants are co-orbiting each other. I'd consider that co-orbiting gas giants is definitely anti-Sol-like, so that just leaves us with the 2-gas-giants list to trawl through - that's 15 systems.
