Episode Transcript
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The following in Foecast is a presentationof the Xoon Broadcast Network, Xoon TV
Channel and Roma McConnell Media Company broadcastin from Canada to the World and beyond.
Why scientists can't give up the huntfor alien life. Despite all we've
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learned about ourselves and the physical realitythat we all inhabit, the giant question
of whether we're alone in the universeremains unanswered. We've explored the surfaces and
atmospheres of many worlds in our ownSolar System, but only Earth shows definitive
signs of life past or present.We've discovered more than five thousand exoplanets over
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the past thirty years, identifying manyEarth sized potentially inhabited worlds among them.
Still, none of them have revealedthemselves as actually inhabited, although the prospects
for finding extraterrestrial life in the nearfuture are tantalizing. And finally, we've
begun searching directly for any signals fromspace that might indicate the presence of an
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intelligent, technologically advanced civilization through endeavorssuch as SETI, the Search for Extraterrestrial
Intelligence, and Breakthrough Listen. Allof these searches have returned only no results
so far, despite memorably loud claimsto the contrary. However, the fact
that we haven't met with success justyet should in no way discourage us from
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continuing to search for life on allthree fronts to the limits of our scientific
capabilities. After all, when itcomes to the biggest existential question of all,
we have no right to expect thatthe lowest hanging branches on the cosmic
tree of life should bear fruits soeasily. Each of the three main ways
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we have of searching for life beyondthe life that arose and continues to thrive
on planet Earth has its own setsof advantages and disadvantages. We can access
the surfaces and atmospheres of other worldsin our solar system, enabling us to
look for even tiny microscopic signs ofbiological activity, including imprints left by ancient
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now extinct forms of life, butwe may have to dig through tens of
kilometers of ice to find it,or recognize life forms wholly unrelated to life
as we know it on Earth.With thousands of exoplanets now known, the
imminent technological advances that will enable transitspectroscopy and or direct imaging of Earth sized
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worlds could lead us to discover livingplanets with unmistakable biosignatures in their atmospheres.
If life driving on an Earth sizedworld is common, positive detections are only
a matter of time and resources,and searches for extraterrestrial intelligence offer the most
profound rewards, a chance to makecontact with another, perhaps even a technologically
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superior intelligence species. The odds areunknown, but the payoff could be unfathomable.
For these and other reasons, theonly sensible strategy is to continue to
pursue all free methods to the limitsof our capabilities, as without superior information,
we have no way of knowing whatsorts of probabilities any of these methods
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will have of yielding our first positivedetection. After all, absence of evidence
is not evidence of absence, andthat saying certainly applies to life in the
universe. From a cosmic perspective,the laws that govern the universe, as
well as the nature of the componentsthat make it up, indicate that the
potential for life as a common occurrencemight be absolutely inevitable. Initially, at
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the start of the hot Big Bang, our universe was hot, dense,
and filled with particles, antiparticles,and radiation moving at or indistinguishably close to
the speed of light. In thesebeginning stages, neither the ingredients nor the
conditions necessary for chemical based life werein place. The universe was born life
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free, and yet as time wenton, the potential for biological activity would
rise and rise. As the universeexpanded and cooled, the following steps sequentially
occurred. The particles and antiparticles annihilatedaway, leaving a tiny excess of matter
behind. Quarks and gluons formed boundstates, giving rise to protons and neutrons.
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Fusion reactions occurred, creating the lightelements. Atoms formed from these atomic
nuclei, and the surrounding bath ofelectrons. Gravitational contraction and collapse takes place,
giving rise to stars, Star clusters, and other clumps of matter attract
forming galaxies, and within those galaxies, successive generations of stars are formed,
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creating heavy elements. Once a galaxybecomes enriched enough with these heavy elements,
the new generations of stars that followcan form, with rocky worlds within those
stellar systems, many of which willhave the potential for life. Within our
observable universe. Since the dawn ofthe hot Big Bang, sextillions of stars
have formed. Of those, themajority of them are found in large,
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massive, rich galaxies, galaxies comparablein size and mass to the Milky Way
or greater. By the time billionsof years have gone by, most of
the new stars will have sufficiently largefractions of heavy elements to lead to the
formation of rocky planets and molecules thatare known as precursors to life. These
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precursor molecules have been found everywhere,from comets and asteroids to the interstellar medium,
to stellar outflows to planet forming disks. And at this critical step we
find ourselves face to face with theend of our scientific certainty. Where and
under what conditions does life come intoexistence? On those worlds where life arises,
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how frequently does it survive and thrive, persisting for billions of years?
How often does that life saturate itshabitable regions, transforming and feeding back on
its biosphere where this occurs, howoften does life diversify, becoming complex and
differentiated, And where that occurs,how frequently does life become intelligent enough to
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become technologically advanced, capable of communicatingacross or even traversing the vast interstellar distances.
These questions aren't merely there for usto philosophically ponder. They're there for
us to gather information about and eventuallyto draw scientifically valid conclusions about such probabilities.
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Of course, there are plenty ofvalid explanations for why we haven't succeeded
in our searches for life just yet. The most sobering and the most pessimistic,
is that it's possible that one ormore of the steps required to give
rise to the type of life wouldbe sensitive to are particularly difficult, and
only rarely can the universe achieve them. In other words, it's possible that
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any one of life sustained life,complex and differentiated life, or intelligent and
technologically advanced life are rare, andnone of the worlds we've surveyed possessed them.
That's a possibility we have to keepin mind so long as we're committed
to remaining intellectually honest. But there'sno reason, at least so far to
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suspect that's the primary reason we haven'tdiscovered life beyond Earth just yet. The
old saying, if at first youdon't succeed, try try again. Applies
wherever. The odds of success areunknown, but we have every indication that
success is possible under the right circumstances. Here on Earth. The evidence strongly
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indicates that our home planet is anexample of such circumstances, and hence it's
likely that there are places all throughoutspace and time where life sustains itself,
evolves to become complex and differentiated,and achieves a level of technological advancement sufficient
for interstellar communication. The big unknownsare in the probabilities of the various types
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of alien life that are actually outthere, not in the question of whether
such achievements are possible within our universe. That doesn't mean that we should take
seriously every claim that's been made,even by scientists, that alien life has
been found. The Wow signal,for example, was a high powered radio
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signal received over the span of seventytwo seconds back in nineteen seventy seven.
Although its nature is unknown, ithas never been replicated, either back at
the original source or anywhere else.Without confirmation or repeatability, we draw no
affirmative definitive conclusions. Fast radio bursts, like many signatures observed astronomically, appear
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in many locations both in and outof our galaxy, but have no indication
that they were intelligently created. Theyare likely simply a natural astronomical phenomena whose
origins have yet to be determined.NASA's Mars Viking Lander conducted numerous tests for
life on the Martian surface, withone experiment, the labeled release experiment,
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giving a positive signature. However,the possibility of contamination, the lack of
reproducibility, and the lack of averified follow up experiment has cast tremendous doubt
on the biological positive interpretation of theexperiment. And despite the possibility of encountering
interstellar space probes, direct alien contact, or even the ubiquity of alien abduction
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stories, no robust verification of anyof these claims has ever come forth.
We have to keep our minds openwhile at the same time remaining skeptical of
any grand claims. The conclusions wedraw can only be as strong as the
supporting evidence for them. It's primarilyfor these reasons. We have every indication
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that the universe has all the necessaryingredients for life, but no indication that
we've found it just yet. Thatit's so vital to keep looking in a
scientifically scrupulous way. When we doannounce that we've found extraterrestrial life, we
don't want it to be another instanceof crying wolf with insufficient evidence that we've
found a wolf. We want theclaim to be supported by overwhelming, unassailable
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evidence. That means building fleets oforbiters, landers, sample return missions,
and laboratory equipped rovers to explore awide variety of worlds in our Solar System
venous atmosphere, Mars surface, Titans, lakes, and the oceans of Europa,
Enceladus, Triton, and Pluto,among others. That means building superior
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coronographs on world class space based andground based telescopes, considering the construction of
a star shade, and investing intransit spectroscopy. By imaging the atmospheres and
surfaces of exoplanets, including breaking downtheir molecular and atomic constituents and abundances,
over time, we should be ableto identify any world with a life saturated
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biosphere. And that means continuing tosearch with greater precisions and sensitivities across the
electromagnetic spectrum for any signals that mightcome from an intelligent species seeking to communicate
or announce their presence. If youdon't find fruit on the lowest hanging branches,
that doesn't necessarily mean you give upon the tree. It means you
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find a way to climb higher wherethe fruit may be present but out of
your present reach. This might alsoinclude expanding our searches for extraterrestrial intelligence.
While most searches focus on far reachingradio transmissions, it's possible that alien civilizations
who seek to communicate across the starsand galaxies will rely on a different technology.
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Perhaps we should be monitoring the talesof water maser lines or the twenty
one centimeters spin flip transition of hydrogen. Perhaps we should be looking for patterns
in pulsar signals, including correlating signalsbetween pulsars. Perhaps we should even be
looking for extraterrestrial intelligences in gravitational wavesignals that we have yet to discover.
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Wherever a signal can be encoded bya sufficiently advanced species, humanity should be
looking and listening. There are alsoavenues to explore that won't reveal alien life,
but could help us understand how itarose and arises throughout the universe.
We can recreate the atmospheric conditions foundon other worlds, or even as they
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were on Earth long ago. Inthe lab, with an eye toward recreating
the origin of life from nonlife,we can continue exploring the possibility of having
nucleic acids RNase, DNase, evenponase. Peptide based nucleic acids coevolve with
peptides in an early prebiotic environment,perhaps the most compelling candidate for how life
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first arose on Earth. The rewardsof finding out that we're not alone in
the universe would be immeasurable. Perhapswe could learn how to survive the great
environmental threats that face us hazardous asteroids, a changing climate, or violent space
weather events. Perhaps there are evenmore important lessons to be learned about how
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to overcome our own insufficiencies as humanbeings, the great challenge of moving beyond
our primal nature. Perhaps other civilizationshave success stories to offer us, recounting
how in the early days of theirtechnological infancy they overcame such issues as over
consumption, where they devoured their planet'sresources beyond the point of sustainability, short
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term thinking, where they addressed theimmediate urgent problems at the expense of long
term ones that threaten their existence orthe emergence of disease, famine, pestilence,
and ecological collapse resulting from the globalchanges wrought by a post industrial society.
Our impulses toward greed, plunder andself gratification may not be unique,
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and there may be more experienced,wiser species out there that have figured out
solutions that elude us today. Perhaps, if we're lucky, they may have
lessons waiting in the wings for usthat could guide us toward a more successful
future. Many of us can imaginetwo different futures unfolding for the enterprise of
human civilization. There's the one weshould strive to avoid, where we resort
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to in squabbling over the limited resourcesof our world, descending into ideologically driven
wars, and ensuring our own eventualdestruction if we never find life beyond Earth,
never find anyone else to communicate with, exchange information and culture with,
and to give us hope that there'sa future for humanity out there among the
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stars. Perhaps extinction will indeed beour most likely outcome, But there's another
possible outcome for humanity, a futurewhere we come together collectively to face the
gargantuan challenges facing humans, the environment, planet Earth, and our long term
future. Perhaps the discovery of lifebeyond Earth, and potentially of one or
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more intelligent space faring extraterrestrial civilizations,might give us not only the guidance and
knowledge we need to survive our growingpains, but something far grander than any
terrestrial achievements to hope for. Untilthat day arrives, we must make do
with the knowledge that at present wehave only one another to extend our kindnesses
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and compassion to. To listen toall the shows on the x Zone Broadcast
Network, visit www dot XZBN dotnet To watch the x Zone TV channel.
Exclusive to SIMILTV, visit www dotsimiltv dot com channel thirty two.
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Our motto is Dare to Believe,Dare to be heard. The x Zone
searching for answers, demanding the truth. Do you have any comments, suggestions,
show ideas, Send them to adminat RELHIFMA dot com. For Rama
McConnell Media Company in London, England, I am brookemaguire.