THE SOUTHWORTH PLANETARIUM

70 Falmouth Street      Portland, Maine 04103

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43.6667° N    70.2667° W 

Founded January 1970

2022-2023: XXXIX

Sunrise: 6:34 a.m.

Sunset: 4:17 p.m.

Civil twilight ends: 4:47 p.m.

Sun's host constellation: Libra the Scales

Moon phase: Waning Gibbous (83% illuminated)

Moonrise: 7:08 p.m.

Moonset: 11:34 a.m.

Julian date: 2459898.21

"Art is not what you see, but what you make others see."

-Edgar Degas

THE DAILY ASTRONOMER Monday, November 14, 2022

Wait, Could We Be Alone?

Absolutely, undeniably, categorically, irrefutably, most assuredly, one hundred and one point one percent not! Honestly, as of this writing, astronomers have confirmed the existence of 5271 exoplanets, or planets in orbit around other stars. Based on these detections, we can estimate that our one galaxy could harbor 1 - 3 trillion planets. Let's assume that we're the type of sour-souled buzz-kills capable of frosting palm trees with a single glance and so estimate that only 0.001% (one in a hundred thousand ) of these planets could give rise to life. That would still give us 10 - 30 million life-bearing planets in our own galaxy.

While neglecting the innumerable galaxies boasting comparable stellar populations, we pose the question:  Could anyone possibly suggest that Earth is  the only life-harboring world in the cosmos?  No Vulcans with their impeccable logic.  No Daleks with their propensity for indiscriminate violence.  No phosphorescent fern-craving Blagunsdtrungs, pi-worshipping neo Archemedians or galaxy enslaving Empires or Encyclopedia Galactica?   Utterly  preposterous.   

Or, is it?

A research team at the Jet  Propulsion Laboratory has recently revisited the now notorious "Filter Theory," introduced by George Mason economist Robin Hanson.      This theory posits that other alien  worlds have and perhaps still even do exist. However, these races will all annihilate themselves before attaining technology requisite for space travel.     Consequently, even if we are not technically alone, it will seem as though we are until, of course, we destroy ourselves and vanish from the cosmos altogether.

This filter theory is based on, what else, our own example.    Consider the threats we have confronted and might face in future:   catastrophic asteroid impacts, nuclear annihilation, the dominance of AI and subsequent extermination of the lesser biological beings, and, of course, the ultimate consequences of accelerated climate change induced by fossil-fuel consuming humans.     The presumption -again, based solely on our own history- is that prior to attaining space-faring technology, extraterrestrial races would have to proceed through the same intervening stages through which we have already passed:  development of nuclear technology, exploitation of fossil fuel reserves and the advent of artificial computing capabilities.  Each of these aforementioned developments can pose an existential threat to our species.        

Although we still exist, it is possible that we will obliterate ourselves long before we are able to even reach the nearest star, Alpha Cenatauri, let alone the more far-flung regions of the Milky Way Galaxy.*  Remember that humans haven't ventured farther than about a quarter of a million miles from Earth.  Moreover, our most distant spacecraft, Voyager 1, is only about 22 light hours from home.  Alpha Centauri is 4.3 light YEARS away.

So, perhaps the answer to Dr. Fermi's question, "Where is everyone?" is simply that either no aliens exist anymore or that they'll all be destroyed before they can manage to travel among the stars.  Or, and this notion is quite chilling, there is a dominant alien race that kills off those species as soon as they become star-faring.         

Or, maybe, Dr. Fermi, they exist in great abundance, but we haven't yet managed to detect them.  Perhaps the Milky Way Galaxy teems with life in all areas.   We just haven't matured enough as a race to associate with them.         Again, it is all speculation and, as such, allows for all manner of theories and ideas.    We just happen to prefer the optimistic ones.   

*We are assuming that even if we manage to travel out among the stars, we'll stay within our home galaxy.   Unless, of course, we figure out a way to both manufacture a TARDIS and find a time lord that would like to spend at least a little time away from Earth.   

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