EM isn't really EM - it's passive gravimetric (or gravitic or whatever you want to call it). In other words, it is the passive equivalent of the active sensors.
Huh! That's definitely not obvious, but it makes me feel better to know. :) (And UnLimiTeD, putting out an EM pulse and looking for distortions is called 'radar'. :) Presumably the reason why it isn't used in Aurora is that the gravitic "EM" is so much better. It seems to be superluminal for one thing, but I'm not EVEN gonna open up that can of worms!)
And yes, you're right about the 1/r^4, but for game play purposes Steve has lowered the fall-off exponent for most of the sensors in the game (i.e. most of them are linear fall-off, rather than quadratic or quartic as IRL).
Interesting. Actually, I've been thinking that the sensor ranges seem kind of low. I mean, we have "thermal sensor buoys" up *right now* of incredible sensitivity. The one thing they lack (from an Aurora perspective) is fast all-sky scan - but then, we haven't been motivated to put up probes with that ability. With TN, I'd imagine we could spot a ship drive from the edge of the solar system pretty easy.
I suppose the solution here is just to SM myself a bunch of thermal from the start. Not sure how to give it to everyone else, though.
If you search back through the boards, you'll find huge conversations about this - I think it was while Steve was introducing sensor resolutions ~3 years back.
Thanks, I'll check it out and report back if it seems good to do so.