Condolences, comrade. The furthest I've been out is about 1,600ly and I'd have cried for weeks if I'd lost that data.
I'm sure I can't be the first to have suggested this, but wouldn't it be great if explorers could fit their own black box that always survives ship destruction, so you could head back out to your last known location and have a fair chance of retrieving it? It could add additional gameplay elements too; advanced discovery scanners could be tweaked to detect other people's lost data, giving a sense of urgency to retrieving it before another explorer fortuitously stumbles upon it. And of course it would give pirates a good reason to go after otherwise-empty explorer ships as they crossed the twilight zone on the way back to civilisation. There are already "trade data" canisters in USSs, so it's almost as though FD toyed with this idea then dropped it.
Of course all of this begs the question of why trade data can't fit into the magic escape pod and be brought back to the last-docked station along with the pilot, but then I guess sometimes gameplay needs to trump logic.