# Reasonable stellar body stats

I'm working on a video-game (just a hobby) and I'm trying to strike a balance between scientifically accurate enjoyable to explore. I have here a table of the star types I plan to use. (yes some "stars" are nebulae, for the most part we can ignore those.) I originally did good research to find accurate(ish) data then I slimmed down my categories and manually played with some of the values to make it feel more reasonable for game play-through experience.

My question is if anyone prone to yelling at things for inaccuracy see anything here that would just set you off.

## 1 Answer

There is about 1 brown dwarf for every 5 stars. White dwarfs in the field would typically have a mass of $$0.6 \pm 0.2 M_\odot$$ and a luminosity of $$10^{-5}-10^{-3}L_\odot$$. Their frequency is about right. Neutron stars should be around 10% of the white dwarf number, the masses are about $$1.4\pm 0.2M_\odot$$ and their luminosities could be practically zero.

The binary star frequency is too low. It should be around 30-40% of all systems. Depends a bit on what separations you are considering.

If you look at the local 1000 stars, a couple are red giants (masses could be as low as around $$1.5M_\odot$$), but no blue giants, supergiants or hypergiants. The luminosity of these is a bit low - should be at least the cube of their mass in solar luminosities.

• because of game mechanics, the binary stars are going to be a bit unrealistic regardless. I'm throwing a few "close binaries" in the mix that in reality would make a system relatively uninhabitable. Any more distant binary systems are treated as separate system. I may have reduced brown dwarf frequency too much, I'll trade that with some other dwarf planets. I originally had the super/hyper giant frequency/1000 as decimals, but upped it so the player has a greater chance of finding one... I can drop both to 1/1000 to increase the rarity. thanks for luminosity adj. too Nov 20, 2023 at 21:54
• {"Brown Dwarf: 220", "Red Dwarf: 300", "White Dwarf: 100", "Yellow Dwarf: 335", "Binary Star: 10", "Neutron Star: 10", "Blue Giant: 4", "Red Giant: 10", "Super-giant: 1", "Hyper-giant: 1", "Emission Nebula: 5", "Supernova Remnants: 2", "Dark Nebula: 2"} - - - would you accept that as minimal artistic license? a balance of accurate and engaging? With brown dwarf planets' very marginal and tiny habitable zone, they will be less enjoyable to explore. Nov 20, 2023 at 22:03
• I would say brown dwarf 150, red dwarf 470, white dwarf 150, yellow dwarf 185 would be more realistic. Nov 20, 2023 at 22:47
• You could get rid of them completely as a place to visit... Just because you can go somewhere doesn't mean you need to.... If you know that brown star systems are going to be boring and lifeless.. Then why would a dashing brave explorer in search of adventure go to one??? Leave them as visual fluff but make them not visible is what I would do. Nov 21, 2023 at 16:46
• @Questor, a good suggestion! I'm leaving them in as they are good places to setup relay stations, mining operations, I'm just trying to avoid the player feeling like all they find are brown dwarfs. /// I'll probably just take something close to ProfRob's above suggestion. between the red and yellow dwarfs, up to half the systems visited will have the potential to harbor life. /// Now the question is just what percentage of decent planets in the habitable zone should have life! I know red dwarfs are marginal candidates, but life has managed to fill wild niches here on earth. Nov 22, 2023 at 1:04