The millions of Thargoid scout mapping ships must have invisibility cloaks, as not a single one has ever been spotted.
That's not unreasonable:
- they spend just a couple of minutes in each system in this model, so the chance of overlapping at all with a human explorer is basically nil
- Thargoids don't normally use supercruise for in-system flight so wouldn't be obvious even if they were in the system at the same time
- virtually no explorers routinely check the signal source part of the FSS band just to make sure they aren't all "degraded threat 0" this time, so even if there was a Thargoid lurking in the system as a NHSS they probably wouldn't notice it
- obviously without that check the chance of coincidentally being in normal-space visual range is also near zero for two ships in the same system no matter how long they both spend there
- in the really unlikely event of a meeting between the two the Thargoids can ensure secrecy if they want to
That said, there are at least two recorded (probable or confirmed) meetings between Thargoids and deep space trips, and a few more possible:
- probable: logs found at
https://canonn.science/codex/conflux-beta-site/
- confirmed: recent Galnet report
https://elite.drinkybird.net/?guid=64d34db733102b3f330c545d (though probably they
wanted to be seen, that time)
We have no useful information on the service lifetime of a Thargoid sensor, but multiple decades as a minimum certainly doesn't seem unreasonable based on similar human technology. If we say a 50 year refresh cycle then the chance of overlap is about 1 in 5-10 million per eligible system visited; about 7% of systems contain AWs or AGGs, so the chance of overlap on any individual deep space jump for someone not specifically looking for these is well over 1 in 100 million.
Based on the DW2 metric (DW2 had roughly half of all deep space exploration activity while in progress) there are about 15-45 million deep space hyperjumps a year, so you'd maybe get one overlap (in system at same time as a Thargoid explorer) every five years, which then has a bunch of extra conditions to actually be noticed and reported. I'm fine with Frontier simplifying and rounding the odds down to "actually zero", based on that.