Presenting... Alternis! (all royalties go to NovaSilisko for the name)

[tntristan12]

So I was in a different thread on this same sub-forum and I laid out an idea for a possible way of implementing a singular star system outside of Kerbol. Although my suggestion fit within the scope of that thread, I decided it would give it more room to breath if I left it here to be fleshed out. The original post went something (okay, exactly) like this:

You know, I was brainstorming this earlier. I think the way I'd do it if I wanted to make a distant binary system would be to have two stars located very far apart. For the purposes of this discussion I'll use the names Kerbol (starting star) and Alternis (the second star, whose name I stole from NovaSilisko's excellent planet pack). Let's say that when you are closer to Kerbol, you are effectively in its SOI. When you are closer to Alternis, you are in its SOI. When you get halfway between the two, they alternate.

When you are in Kerbol's SOI, Alternis orbits Kerbol. When you switch to Alternis' SOI, Kerbol starts orbiting it in the opposite direction. Because there are no other points of reference (this approach limits the entire game to exactly two star systems), you would not be able to tell this switch had occurred: the skybox would give nothing away. You could further sell this illusion by hacking out the orbit lines in the map mode. Because the stars would be so far apart, relative motion would be very difficult to detect. The orbits would be so wide that in the time it took you to go from one to the other, it would appear as though they were moving in straight lines if at all, making navigating it very easy.

This addresses both primary developer concerns:

1) Because you could make the argument of this as a binary system, the devs (or modders) would be able to allow a combination of conventional propulsion and high time warp to make transit times reasonable (I would say several minutes - up to 15 at max warp is reasonable) without the need for warp. This would open the market for mod makers to implement their own warp ideas.

2) Since there's only one other star system there is no need to make it randomized. The devs could use a fixed seed to procedurally generate its planets and that would solve the issue of gameplay being different for different players.

A solution like this is something I feel would make everybody happy. It would be the other star system many people on this forum including myself have advocated, it would adhere to the loose standards of realism required by the devs, and it would be close enough to be reachable on conventional means yet far away enough to present a true interstellar challenge to anyone who wants it.

Thoughts?

I think that post adequately covers it, but in the interest of adding something new to the conversation I created this useful graphic:

[chaos_forge]

I think an implementation of the Barycenter system discussed in this thread almost a year ago, now, (link in my sig) would be a better approach than the more ad-hoc method of handling the SOI's that you describe here. Also a barycenter system is more easily expandable in general.

[tntristan12]

Right you are. I was actually thinking about that whole conversation as I was brainstorming. It certainly would apply here! However, there'd be no real need for outer SOI limits since there'd only be two stars. Kind of like how Kerbol's SOI extends outward to infinity right now. Allowing for at least the possibility of outer limits might make it possible for a third, more distant star to orbit both Alternis and Kerbol, not unlike how Alpha Centauri C orbits its companions A and B (which are orbiting each other)

EDIT: Is there any way you could pull up those old graphs? I can't seem to find the thread!

[chaos_forge]

EDIT: Is there any way you could pull up those old graphs? I can't seem to find the thread!

It's in my sig. Also, link for convenience: click here

The main problems with the system were 1) how to deal with two object rotating at different distances from the barycenter but with the same period, and 2) how to implement non-spherical SOI's. Also, because of the game-engine-central nature of this idea, it's very unlikely that a proof-of-concept mod could ever be created. Either the devs hop on to the idea, or it doesn't happen.

Edited May 13, 2014 by chaos_forge

[tntristan12]

Ah, yes. This was the post I keep remembering the most. Just as a point of interest, the gravitational potential scalar function looks like this in the plane of the ecliptic using the "Horn Brain Method":

EDIT: here is a quick plot and % error plot made using the corrected formula and the same mass ratio (4) as with the other plots I posted before

http://www.alemor.org/~mario/uploads/mathematica_barycenter8.jpg

http://www.alemor.org/~mario/uploads/mathematica_barycenter_error8.jpg

I imagine Alternis going at the smaller one, though it'd be interesting if Alternis was instead a blue or red giant and was actually at the larger one! Man, it feels weird to finally revisit this stuff.

[Vanamonde]

I regret to remind you folks that additional solar systems and planets is one of the topics that has been placed on the What Not to Suggest List, as one of the subjects discussed so endlessly that it tends to clog up the forum. The thread will be closed now.