My search-fu is failing me. Is there any consistent indicator of a mirror universe incursion? Some funky radiation or a weird Trek particle or some such? Something that a science officer might make a note of in a log entry shortly before all hell breaks loose? There is plotting and planning afoot for an upcoming episode in ye olde campaign, and it’s giving me a headache.
You mean, apart from moustaches?
As far as I recall, mirror universe stories always came with surprise. But both Kirk and his crew in TOS 2x10 “Mirror, Mirror” and Kira and Bashir in DS9 2x23 “Crossover” felt dizzy after going over to the mirror universe. That’s the only telltale-sign I know of.
remember that in 2371 Starfleet just change insignia. Something mirror universe infiltrators might not know (as many cultural details)
A teleporter checkup might also indicate a problem.
Counting life signs on board
The lighting aboard Terran vessels and installations is darker, because Terrans eyes are much more sensitive to bright light.
The possibility exists that I was unclear. I’m not looking for something to scan for after Captain Goatee shows up, to prove he’s not from around here. I’m looking for precursors, something to notice just before someone comes calling unannounced.
I don’t think there is, which leaves me free to make something up, but I hate to reinvent the wheel if I can avoid it.
Like a flag of Terran Empire in the room?
Like a funky particle or odd radiation or something. Time travel always has strange chroniton emissions and whatnot, for instance.
I’m quite sure that Starfleet prevented some stars turning supernova that Terran Empire didn’t care about. They should have disappeared in the Terran universe. They might even make others disappeared too to get rid of the inhabitants, so the stellar map is different .
Also dimensional shift could/should implied at least a little time shift (enough to send a warning)
As I said: transitions to the mirror universe, to my knowledge, always came with surprise.
That is, mirror universe stories never followed a path of “oh, we should have known before it happened!”. That would be a new element to that specific plotline.
- TOS 2x10 “Mirror, Mirror” began with negotiations about mining rights, before a transporter malfunction sent Kirk, McCoy, Scotty and Uhura into the mirror universe.
- In DS9 2x23 “Crossover”, Kira and Bashir return from the opening of the hospital on New Bajor in the Gamma Quadrant, when an accident within the Bajoran Wormhole sends them into the mirror universe.
- In DS9 3x19 “Through the Looking Glass”, Mirror-O’Brien kidnaps Sisko all of a sudden.
- In DS9 4x20 “Shattered Mirror”, Jake Sisko goes from the promenade into his quarters, being shocked to see the mirror-variant of his dead mother.
- In DS9 6x08 “Resurrection” there actually is something fortelling the appearance from someone from the mirror universe – only seconds, before mirror-Barail appears on the transporter pad and presses a phaser against Kira’s back. More on that later.
- DS9 7x12 “The Emperor’s New Cloak” is a litte off here, because Quark and Rom enter the mirror universe on purpose, after learning that Grand Nagus Zek was kidnapped.
Two-part ENT 4x18 and ENT 4x19 “In A Mirror, Darkly” entirely takes place in the mirror universe with no interaction with the “main cast”, if I remember correctly (has been a while) and I cannot comment on the seven(!) DIS Episodes (1x09–13 and 3x09–10) that deal with the mirror universe as I have not yet seen anything from Discovery.
But what we can take from TOS and DS9 is: Mirror Universe stories always come “Bam! In your face! It’s mirror universe time!” without anyone having a moment to prepare themselves. This is even true to “The Emperor’s New Cloak” as Quark and Rom are totally caught off-guard and instantly kind-of-panic.
If you want to have a tell-tale sign, tie them to the transporter, I would say. First, the first encounter (at least in broadcasting order) with the mirror universe was the result of a transporter malfunction. This was brought up again in “Crossover” when mirror-Kira (the Intendant) tells Kira that transporters were re-designed to prevent accidents like in “Mirror, Mirror”. Finally, in “Resurrection”, mirror-Bareil uses a modified transporter to come to DS9 – and this is the only instance where there was some tell-tale, als O’Brien notices a strange transporter signal, only a glimpse before Bareil arrives. So, there was a tell-tale but it left the cast no moment to really react.
For foreseeing things there’s also the Prophets or Psi powers
To append @MisterX list:
ENT 4x18 and ENT 4x19 “In A Mirror, Darkly” connect the Mirror Universe with TOS 3x09 “The Tholian Web”.
In DIS 1x09 “Into the Forst I Go” it was an incomplete navigation sequence which led to Discovery entering the Mirror Universe.
In DIS 3x09 “Terra Firma, Part 1” and DIS 3x10 “Terra Firma, Part 2” it happened by stepping through a door (the disguised Guardian of Forever).
In my campaign, the crew got sent to the Mirror Universe when they beamed away and a bomb hit the transporter room at the same time. The radiation and energy spike and such caused the transporter beam to be sent to the Mirror Universe where a transport was happening at the exact same time.
The crew escaped after they stole a Defiant-class ship and initiated a static warp shell in the Barzan Wormhole, which re-routed the wormhole to the Prime Universe. Technology is weird.
I don’t think there are any established tell tell signs, but you could certainly create some for really specifically tuned sensors.
If I was going to do this, I would probably look at the readings produced by a wormhole as inspiration for key words, but at a substantially lower level (possibly barely indecipherable from normal background readings)
Mostly trying to make so this get-a-lifer won’t gig me on things when the time comes. Thanks, guys.