One of the beneficial outcomes of searching for life in the universe is that it grants greater awareness of our own problems here on Earth. Lack of contact with alien beings to date might actually comprise a null “signal” pointing humankind towards a viable future. Astrobiology has surprising practical applications to human society; within the larger cosmological context of cosmic evolution, astrobiology clarifies the energetic essence of complex systems throughout the universe, including technological intelligence that is intimately dependent on energy and likely will be for as long as it endures. The “message” contained in the “signal” with which today's society needs to cope is reasonably this: only solar energy can power our civilization going forward without soiling the environment with increased heat yet robustly driving the economy with increased per capita energy usage. The null “signals” from extraterrestrials also offer a rational solution to the Fermi paradox as a principle of cosmic selection likely limits galactic civilizations in time as well as in space: those advanced life forms anywhere in the universe that wisely adopt, and quickly too, the energy of their parent star probably survive, and those that don't, don't.

The context

A few years ago, I had the pleasure of attending the 50th anniversary of Project Ozma – the first dedicated search for extraterrestrial intelligence (SETI) conducted by Frank Drake in 1960. The celebratory gathering was held at the National Radio Astronomy Observatory in Green Bank, West Virginia, where that initial search was attempted and where I had in the intervening years operated dozens of radio-frequency experiments of my own, including a few unauthorized reality-checks for signs of otherworldly life. Although I never detected there any signal implying contact, I often wondered why not. Astronomers are commissioned by society to keep our eyes on the sky, yet we have never found any unambiguous, confirmed evidence for life beyond Earth. Are alien civilizations out there but not advanced enough to betray their presence? Or are they so advanced they are actively hiding from us? Perhaps they just don't exist at all, thereby ensuring that we are alone in the observable universe.