Lumenna-Súnáris System (1): The Stars

(So post. Such computation. Wow.)

Okay, folks, here we go, the Lumenna-Súnáris System. A little bit slower than expected, because it turns out that it actually takes quite a long time to gather up and re-double-check all my figures with great care.  Since I know you guys, y’know?

So starting with this post, which covers the suns, I’m going to try and hit up one planet a day, with its moons, other statistics, and a few interesting facts about it. Hopefully, it is planned, not to the exclusion of any other content.

So, let’s get started. To sum things up, first, the System is a Population I far binary (the stars vary in distance from 125 au to 358 au during their 2,864 local year orbit) which gives their worlds a nice “deep seasonal cycle” to pay attention to as well as their regular ones.

For convenience, in this description, we’re going to pretend that Lumenna is the center of the system and everything orbits around it rather than mucking about with barycenters. It has nine planets and an asteroid belt; Súnáris has eight planets and an asteroid belt; and then, of course, there is Múrcár. (If you’re into Kuiperians.)

Also, since if anyone does put this into a KSP mod it would be nice for them to start from the start, this is the system raw. Which is to say, this data reflects that status quo as of 2050, before anyone got clever ideas about strapping nuclear weapons to their ass and launching themselves into the wild black yonder, and certainly before people started colonizing other worlds, building habitats all over the place, moving inconvenient moons to better locations, girdling the equators of gas giants with supercolliders, reengineering the suns, or other cool stuff like that.

And a final word: through all of this, please pardon my eclectic mix of units; that’s just how I roll. Time units prefixed with T- indicate that I’m using your Earth hours/days/years, not the local calendar.

So let’s get started, shall we?

I. Lumenna

Mass: ~1.0 solar masses
Spectral class: G2V
Temperature: 5,800 K
Luminosity: 0.82 sol
Radius: 381,100 miles

“the Sun”; the yellow-white G2V star that everyone thinks of as the system primary even though it’s, technically, not really a concept that works all that well with binaries.

II. Súnáris

Mass: ~0.75 solar masses
Spectral class: K2V
Temperature: 4,900 K
Luminosity: 0.24 sol
Radius: 288,100 miles
Orbit (avg.): 242 au
Orbit (ecc.): 0.48
Orbit (period): 2,845.69 years
Perihelion: 125 au
Aphelion: 358 au

The system’s secondary star, slightly smaller and cooler than Lumenna, with light more orange. It’s name glosses as “shining one”, because its presence in the heavens overshadows all the other stars therein.