by David Garofalo
If you want to know whether intelligence lives elsewhere in the universe, you need to understand black holes. Black holes affect galaxies, stars, and in turn, their planets. When matter falls onto black holes, winds and jets may form that enhance or suppress the rate of star formation, push stars around, heat the interstellar environment, and cause havoc on planets by spraying them with X-rays, or not. The kind of feedback on planetary systems depends on the kind of galaxy, its formation history, and how it fed its black hole. We can now hone in on the locations where habitable planets formed in abundance and life there was left undisturbed so that it could have thrived.
We can now identify when and where black holes enhanced star formation but failed to suffuse their host galaxy with a hot X-ray halo as is typical of many massive black holes. And in a recent study (linked below), this has been done. In other words, we now know where and when in the universe life had the highest probability of evolving undisturbed to its full potential. The answer is in remote, low density environments, that nonetheless involved mergers of galaxies about 11 billion years ago. Intelligence maturing to the point of interstellar communication occurred there around 6 billion years ago. If a subset of such civilizations survived the challenges associated with an ever increasing ability to tap into the energy available to them by their galaxy, we may be able to see the amazing products of their presence, but we have to point our hearing away from the Milky Way and out into the depths of space. The most advanced intelligence in the universe may have left a message for us. It’s time to retrieve it.