The heavens are still silent:
Astronomers who have been listening for signals from alien civilisations in the most intensive hunt for extraterrestrials yet have found no evidence of life in its first year in operation.
The Breakthrough Listen project began to eavesdrop on the universe with the Green Bank observatory in West Virginia in January last year, but the most intelligent transmissions the telescope has picked up so far appear to be from satellites or mobile phones and other Earthly devices. […]
The Green Bank telescope listened for signals in the range from one to two GHz coming from 692 of the nearest stars to Earth. “Our results mean that fewer than 1% of the stars within 150 light years are constantly transmitting in this range, but it doesn’t mean they are not transmitting at all,” Siemion said.
Breakthrough Listen is backed, in part, by Russian billionaire Yuri Milner, who is also funding the Breakthrough Starshot project that aims to send a light-propelled probe to Alpha Centauri.
The total lack of evidence of extraterrestrial intelligence after decades of searching is puzzling, and a little troubling. The problem is known as Fermi’s paradox, which Wiki describes as “the apparent contradiction between the lack of evidence and high probability estimates, e.g., those given by the Drake equation, for the existence of extraterrestrial civilizations.”
See here for a great in-depth treatment. The thing is that there are roughly 10,000 stars in the universe for every grain of sand on every beach on earth, meaning there should be a mind-boggling number of planets capable of giving rise to intelligent life. In our galaxy alone, there should by all rights be some 100,000 advanced civilizations, at least.
And yet… no contact. Not one signal, radio wave, proven visitation, bleep or bloop from E.T. The silence is deafening.
There are, of course, lots of theories to explain this. One group of theories centers around the idea that humans are the first, or the only, advanced civilization in all creation. This seems very unlikely when you do the math. Another group of theories holds that other advanced life forms exist – but are too far away to reach us. Or they have contacted us, just in a format that our simple human brains are wholly incapable of understanding.
Or maybe the aliens are maintaining a deliberate silence. Why would they do this? They could be observing us (this is the Zoo Hypothesis). Or they could be hiding. From what?
From this, of course.
We now understand that the silence of the galaxies is a message of ultimate ominousness. A thing there is, of incomprehensible power, that takes intelligent life for its prey.
Under this theory, any alien race that reaches a certain level of development – the level at which we humans might become aware of its existence across the unfathomable abysses of space – is systematically wiped out by the Exterminator. Think of it as cosmic pest control.
This is why people like Stephen Hawking advocate listening for intelligent life… but not broadcasting to it.