Scenario: Humans have setup an observation/research station close enough to study the super blackhole Sagittarius A*, which in this world is a wormhole. Aliens exist on the other side. (I am flexible whether its a civilization, reserach station, Alien Joe Schmoe's pet radio project, or whatever) Neither civilizations learned/proved wormholes exist yet. Neither civilizations know about each other in any way. The technology to actually travel through the wormhole is decades if not centuries away from this scenario, but some form of information or signal "leaks" through both ways.
This "thing" that leaks through will be at first remain undetected, or thought of as background noise/random natural occurrances. Eventually after decades? centuries? of study they realize it's not random at all, its potential sign of alien life.
Both sides will eventually notice the "leakage" from the other side, albiet perhaps decades apart. Currently, I'm agnostic as to whether the humans or aliens were first. They will naturally try to study it, decipher it, then try to communicate by sending some kind of communcation back.
Question: What might this "leakage" be, how might they gather useful data from it, and how can this lead to eventual communication and have the scenario play out?
- The alien civilization uses a duodecimal system. Any language or computer protocols or deciphering/communication challenges will be influenced accordingly.
- Without changing the scope of the main question, the human observation station is actually unmanned. It is constructed by self-replicating nanorobots fired from an "Alcubierre catapult" (No manned FTL yet. Not to be discussed in this question) with a quantum entangled communication capability to send information back to Humans. (Not to be discussed in this question, will likely just handwave it in) The relevance of this detail to the scope of this question might be whether or not that creates an additional layer of challenge to the scenario, for example, the necessity to build any instruments that wouldn't already be part of the existing blackhole observation/research setup.
- Discussion of anything directly related to the handwaved quantum communication is outside of the scope of this question. Discussion on any effects due to the wormhole such as time difference/lag and its impact on alien contact/communication is within the scope.