THE SOUTHWORTH PLANETARIUM
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Founded January 1970
2022-2023: XXXIX
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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?

[image: istockphoto-1148908658-612x612.jpg]
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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