Anyone know anything about Stellar Forge? (Where are all the white dwarfs?!)

Elyssaen

E
So, I pulled 1,554,243 stars from eddb.io into a database. Wanted to get a feel for stellar distribution, and sometime next week I might post a more detailed thread analysing all this. But now I have a quick question. Here's the breakdown of stars feed into eddb.io:

Code: 
[TABLE="width: 305"]
[TR]
[TD][B]Class
[/B][/TD]
[TD][B]Population[/B][/TD]
[TD][B]Percent
[/B][/TD]
[/TR]
[TR]
[TD]M-Class[/TD]
[TD="align: right"]517,303[/TD]
[TD="align: right"]33.3%[/TD]
[/TR]
[TR]
[TD]K-Class[/TD]
[TD="align: right"]295,670[/TD]
[TD="align: right"]19.0%[/TD]
[/TR]
[TR]
[TD]Neutron Star[/TD]
[TD="align: right"]163,353[/TD]
[TD="align: right"]10.5%[/TD]
[/TR]
[TR]
[TD]F-Class[/TD]
[TD="align: right"]145,079[/TD]
[TD="align: right"]9.3%[/TD]
[/TR]
[TR]
[TD]G-Class[/TD]
[TD="align: right"]119,267[/TD]
[TD="align: right"]7.7%[/TD]
[/TR]
[TR]
[TD]A-Class[/TD]
[TD="align: right"]82,996[/TD]
[TD="align: right"]5.3%[/TD]
[/TR]
[TR]
[TD]Brown Dwarf (L)[/TD]
[TD="align: right"]63,943[/TD]
[TD="align: right"]4.1%[/TD]
[/TR]
[TR]
[TD]Pre-MS (T Tauri)[/TD]
[TD="align: right"]36,585[/TD]
[TD="align: right"]2.4%[/TD]
[/TR]
[TR]
[TD]Brown Dwarf (T)[/TD]
[TD="align: right"]32,981[/TD]
[TD="align: right"]2.1%[/TD]
[/TR]
[TR]
[TD]B-Class[/TD]
[TD="align: right"]32,748[/TD]
[TD="align: right"]2.1%[/TD]
[/TR]
[TR]
[TD]Brown Dwarf (Y)[/TD]
[TD="align: right"]22,026[/TD]
[TD="align: right"]1.4%[/TD]
[/TR]
[TR]
[TD]Black Hole[/TD]
[TD="align: right"]19,406[/TD]
[TD="align: right"]1.2%[/TD]
[/TR]
[TR]
[TD]White Dwarf[/TD]
[TD="align: right"]11,818[/TD]
[TD="align: right"]0.76%[/TD]
[/TR]
[TR]
[TD]O-Class[/TD]
[TD="align: right"]5,056[/TD]
[TD="align: right"]0.33%[/TD]
[/TR]
[TR]
[TD]Pre-MS (Herbig Ae/Be)[/TD]
[TD="align: right"]2,647[/TD]
[TD="align: right"]0.17%[/TD]
[/TR]
[TR]
[TD]Post-MS (Wolf-Rayet)[/TD]
[TD="align: right"]1,452[/TD]
[TD="align: right"]0.09%[/TD]
[/TR]
[TR]
[TD]Post-MS (Pre-Carbon S)[/TD]
[TD="align: right"]692[/TD]
[TD="align: right"]0.04%[/TD]
[/TR]
[TR]
[TD]Post-MS (Pre-Carbon MS)[/TD]
[TD="align: right"]631[/TD]
[TD="align: right"]0.04%[/TD]
[/TR]
[TR]
[TD]Post-MS (Carbon)[/TD]
[TD="align: right"]494[/TD]
[TD="align: right"]0.03%[/TD]
[/TR]
[TR]
[TD]NULL[/TD]
[TD="align: right"]96[/TD]
[TD="align: right"]0.01%[/TD]
[/TR]
[/TABLE]

What I haven't done, yet, is try to distinguish main sequence stars from subgiant, giant and supergiant stars. eddb.io doesn't have data on that, and I haven't found any exact definitions I can work with. (Giant stars have a higher radius, but I'm not sure if there's a specific radius cut-off: I think it's more likely the official cut-off is luminosity-dependent, and we don't have those figures.)

But broadly this distribution makes sense. It's a little strange that there are more F-class stars than the cooler G-class, but I'm no astronomer.

But what really confuses me are the compact stars / stellar fragments: white dwarfs, neutron stars and black holes. Far as I know, these should be something more like 8%, 1% and 0.1% respectively. Instead, there are a lot of neutron stars, too many black holes, and far too few white dwarfs.

The first two discrepancies can be explained: eddb.io only knows about what's been explored, and explorers love black holes and neutron stars. Many will filter onto 'Compact stars', which includes those two but not white dwarfs (not sure why: white dwarfs are just a slightly 'gentler' degenerate stellar remnant, they're absolutely a compact star). And neutron fields are going to be massively over-represented.

But 0.76% white dwarfs? How in the hell? Is Stellar Forge racist or something? Any theories?

(Had some struggle with the systems.csv out of eddb.io, so I can't yet do analysis of stars by their location. But I'm pretty sure white dwarfs are much more common in the bubble than 0.76%.)

(Edit: again, no astronomer, and the 8/1/0.1% figures I read somewhere could be nonsense. But it's surely telling that in real life, the closest white dwarf is 8.6 ly away (Sirius B). Closest known neutron star? Calvera, at least 250 ly away. Black holes I think... not within 1000 ly, right?)
 
Last edited:

mono

mono
Aren't you looking at what people have scanned there? So it would make snese there are more NS/BH as people are deliberately targeting NS/BH for jump boosts/credits.
 

Elyssaen

E
mono said:
Aren't you looking at what people have scanned there? So it would make snese there are more NS/BH as people are deliberately targeting NS/BH for jump boosts/credits.
Click to expand...
I said that. That's why I'm not too worried about the high figures for neutron stars and black holes. It's the really small number of white dwarfs which is the true oddball.

Hm. It's certainly the case that far more stars will become white dwarfs than neutron stars and black holes. But I guess it's also the case that the smaller, more common stars that are destined to be white dwarfs will burn more slowly, so a smaller % of them will have left the main-sequence and become degenerate stars by this point. Still, every estimate I can find is that white dwarfs are not this rare.
 
Last edited:

mono

mono
I tend to avoid them, I'm guessing others do. After travelling many LY around NS fields it's not like there aren't many of them.
 

IndigoWyrd

IndigoWyrd
Is it politically correct to call them "white dwarfs"?
Shouldn't they be "Alternate-Height caucasians"? Or something more sensitive?
 

IndigoWyrd

IndigoWyrd
Elyssaen said:
Who cares what we call them? Doesn't look like there are enough to fight back anyway.
Click to expand...

giphy.gif


It only takes one...
 

Thetele

T
Elyssaen said:
Who cares what we call them? Doesn't look like there are enough to fight back anyway.
Click to expand...

The one in Outotch WG-S d5-0 definitely fights back. And it claimed many victims during distant stars. Some of those hose white Alternate-Height caucasians
white dwarfs
are really deadly to ships passing by.
 

Bonzodog

Bonzodog
As someone thats working on EDDB, and works with the web client plus backend ROSS software, I can tell you now that because a lot of the systems in the bubble are "known" (pre-created by FDev), and thus have never been scannable, no end of the stellar body information about the known systems is missing from EDDB. See, EDMC and ED Discovery only add systems that can be scanned. To add the known systems, it has to be done manually.

Its actually a task two or three of us have taken up - to manually enter and survey all the known populated systems inside the bubble, but more needs to be done. Unfortunately, it means lots and lot of manual data entry work via ROSS, but if anyone else wants to take up this task, feel free to do this. We need all the planetary settlement data adding, system reserve, and upto date station data such as imports/exports/prohibited, and the stellar body they are orbiting or on.

That is why most of the White Dwarfs in the bubble are missing from EDDB.
 
Last edited:

Elyssaen

E
Bonzodog said:
As someone thats working on EDDB, and works with the web client plus backend ROSS software, I can tell you now that because a lot of the systems in the bubble are "known" (pre-created by FDev), and thus have never been scannable, no end of the stellar body information about the known systems is missing from EDDB. See, EDMC and ED Discovery only add systems that can be scanned. To add the known systems, it has to be done manually.

Its actually a task two or three of us have taken up - to manually enter and survey all the known populated systems inside the bubble, but more needs to be done. Unfortunately, it means lots and lot of manual data entry work via ROSS, but if anyone else wants to take up this task, feel free to do this. We need all the planetary settlement data adding, system reserve, and upto date station data such as imports/exports/prohibited, and the stellar body they are orbiting or on.

That is why most of the White Dwarfs in the bubble are missing from EDDB.
Click to expand...
That makes sense. Though the number's still quite low... I read a comment in a historical thread that suggested Stellar Forge was possibly known to not create enough white dwarf stars.

If I wanted to help, where would I start?
 

Bonzodog

Bonzodog
Elyssaen said:
That makes sense. Though the number's still quite low... I read a comment in a historical thread that suggested Stellar Forge was possibly known to not create enough white dwarf stars.

If I wanted to help, where would I start?
Click to expand...

First off, make sure you have an account created on eddb.io. When you look up system information, you will see at the bottom of the page a link to edit the system info on ROSS. Thats where you go, and you can then change all known information about the system.

What I did was start with a home system as the reference point, then just asked it for all populated systems from there in an expanding circle. I then edited and added all stellar body info using the system map in each system as I was in it. Its worth setting up an explorer class ship for this with a DSS - I use a fully explorer equipped DBX. DO NOT use a large pad ship for this job, as you will need to be able to land at outposts in some of the darker extraction systems.

Lots of the systems you go to will be "unexplored", but previously discovered and now in 2.3, even though they have been tagged, you will gets A LOT of credits for simply scanning the system. Make sure to scan everything, as the information will be added to the system map, and you will need to input the entire lot into ROSS.

Plus you will need to scan them to get the system reserve type (which is used by miners). There is a lot of faction data still missing from EDDB, especially the Player Factions, but as of 2.3, with the player journal modifications, that is now being added via EDMC. IF the arrival star is not scannable (always click on it to be sure), then the system is "known" and you should make straight for the nearest starport, where you should then hangar your ship to start editing the system in ROSS.

One piece of advice - don't do this in open. I would use a PG (I'm in MobiusX PG as i'm on XBox), or solo.

The EDCD (this includes EDDB, EDSM, Coriolis etc) devs have a discord server, and the link can be found on the eddb front page.
 
Last edited:

askavir

askavir
Being fair, nobody really knows how many blackholes are in our galaxy, or even how common they could be.

Blackholes are invisible on telescopes, they can only be "detected" (or more accurately, presume their existence) either by radiation or by the gravitational effect they have on neighbouring stars (that's how Sag A was discovered). But that is only possible to observe if their have very high mass.

In the game, only Sag A and the Great Annihilator twin black holes have high mass. All the other black holes in the game are so tiny we could never detect them with out current technological means.
 
Last edited:

Elyssaen

E
askavir said:
Being fair, nobody really knows how many blackholes are in our galaxy, or even how common they could be.

Blackholes are invisible on telescopes, they can only be "detected" (or more accurately, presume their existence) either by radiation or by the gravitational effect they have on neighbouring stars (that's how Sag A was discovered). But that is only possible to observe if their have very high mass.

In the game, only Sag A and the Great Annihilator twin black holes have high mass. All the other black holes in the game are so tiny we could never detect them with out current technological means.
Click to expand...
True. So my background is in theoretical physics, not astronomy, and I find it daunting just how far from first principles astronomy is. (It's why well back in school, I slunk away from biology and chemistry in favour of the first principles approach of physics.)

So, with that context on how I think, I'd expect that astronomers wouldn't model the stellar distribution by just observing it, but by predicting it. And, naïvely, isn't that largely just a function of:

a) the probability distribution of a star of mass M forming,
b) the probability distribution of a star forming over time?

Black holes... big enough to form one, old enough to have collapsed... plug in numbers, predict % population?

Could be totally wrong. Would love the view of an astronomer. I did ask an astro postdoc this but... eh, she didn't seem as interested as I'd hoped.
 
You must log in or register to reply here.
Back
Top Bottom