I think it is Eve Online screenshot, isn't it ?
Let's ignore the wide glow very near engine at the moment - it is easy to do in similar way as longer one.
There are two basic ways to do this - with billboard shape and with few quads. In both cases, you construct long quad (in fact more than 1, but for now let's focus on 1) starting from engine, ending in space and texture it with glow texture. You can probably even manage with 1-dimensional texture, but 2-dimensional should give you more control over shape of end of trail. Then, you make it transparent (do-not-write-depth buffer, src-alpha + dst-one blending to get lighten effect). To make trail visible from all sides, you need to billboard quad (around axis corresponding to movement of ship) or use 2 or 3 quads in form of cross/hexcross(??). 3 quads are a bit more resource expensive, but look at bit better when looked at from behind a ship.
This will of course work only for ship flying in one direction - if you want to make trails which mirror past movement of ship, you will need to divide long quad into smaller segments (here 3-quad idea is even better, as you won't need to billboard hundreds of quads each frame). How many segments ? Make it configurable (maybe even by player depending on power of his GPU). As long as you are not playing lightcycle/TRON with ships, probably 20-500 should be reasonable range to experiment with.
BTW, at some point in past, I have made a java3d loader for eve ships with textures (thus I was able to check how titans and jovian ships look like
). It is trivial to do (at least was a year ago, maybe they have changed a file format since then) - so if you want to play with space game, you could write something like this yourself and use it for internal testing, before you will manage to secure your own models. Of course, I would suggest not distributing anything based on it, or, God forbid, containing some models from Eve - this is just for bootstrapping your engine.
