I wonder what this is …
Engage psudo-science/fiction : So, when you decelerate out of FTL, aren’t you going to give off a lot of Cherenkov Radiation, and doesn’t the transition from hyperspace to realspace carry over a lot of tachyon/dark-matter particles that have to get shed from the ship in a ‘discharging’ action in the relative proximity to a gravity well? And the photons from our gravity well are simply trailing them behind the ship ship and triggering a refraction effect to make it look like a comet tail?
Ok, enough of that, but a boy can dream…
… What ever it is, its gorgeous, and I hope we can get better pictures of it, if not establish communications 