The question of whether to send messages to the stars is fraught with difficulty. The big fear is attracting a more advanced civilization with nefarious intent. Why take the risk?
The same strategy also dramatically narrows the field of exoplanet candidates worth studying in detail for potential contact. In fact, Kerins says this process narrows the search for potentially habitable exoplanets that should be considered for contact to just one.The key idea in Kerins’ approach is mutual detectability. This is the notion that the most fruitful way to search for alien life is to look for places where an observer would have a similar chance of seeing us.
So the best strategy is to confine our searches to exoplanets that would allow a civilization to look for us in the same way as we are looking for them. In that case, both would have information in common. Kerins calls this “common denominator information.” By the law of mutual detectability, the best place to look for other civilizations is in the subset of exoplanets that can observe the Earth by the same method. The most popular way of spotting exoplanets is by looking for the slight dimming of the parent star as a planet passes in front of it.
So if a civilization on K2-155d is using a similar calculus, it ought to be awaiting our call. Whether we make that call or not is still a difficult question.
Nice theory, would be good to draft a similar protocol not for SETI but for anthropogenic panspermia. AKA Earthlings flying to other worlds and populating them with Earthlings.