That being said, there's neither PvE content on the scale to need that, nor PvP density to support it either.
* SNIS is "properly" 3D, as opposed to the "submarine" style limited 3D support Artemis has.
* With the turret gun, SNIS feels a little more "millenium falcon" than "enterprise".
* Graphics in SNIS are miles better, but still no great shakes by modern standards (though the gas giants look awesome, if I do say so myself.)
* Artemis has a lot more mission scripts available. SNIS has a mission scripting system (Lua based), but there are not very many mission scripts.
* Artemis is more properly a game, while SNIS is more of a sandbox. (More mission scripts would help here.)
* SNIS is (I think) comparatively less buggy, and I have run sessions for hours with zero hiccups. I don't get the impression from what I've read that Artemis is quite so stable, but I might be wrong.
* The SNIS server processes are entirely headless with no UI graphical or otherwise, while the artemis server is also the "main screen" client (as I understand it).
* It's possible to have a constellation of SNIS server processes and traverse between them via "warp gates", building an arbitrarily large universe given enough servers to host it all (or, it can auto-start and auto-shutdown servers on a single machine on-demand to give the illusion of an arbitrarily large universe.) Artemis has no similar concept that I am aware of.
There's loads of other differences as SNIS is not really a copycat of Artemis but rather just taking the general idea of a bridge simulator and not much else.
I would be remiss not to mention the existence of another open source spaceship bridge simulator, Empty Epsilon. There's a forum for the genre: https://bridgesim.net
How many players are supported at a time?
I frequently get together with friends and chill on some Discord’s and Slack Channels for gaming.
I can probably scrounge a few people together to give it a go.
Also: shoutout to FOSS game dev. I help out on Cataclysm:DDA, which is also rather large in scope