I’m an Astronomer and Astrophysicist by training and profession and care deeply about all living things, the state of our world and the planet we inhabit. In studying the universe and the natural world most of my life, I have come to learn a few things; among those, I’ve come to learn about the origin of the elements, most notably the origins of Uranium and Plutonium, the essential materials used in either an atomic weapon or in a nuclear fission reactor. You see, all elements in the Periodic Table beyond Helium are synthesized in the cores of stars. In the case of our sun, hundreds of millions of metric tons of hydrogen, through nuclear fusion reactions in its core, are continuously transmuted through nucleosynthesis to form Helium, releasing enormous amounts of energy according to the principle of Mass-Energy Equivalence (E=mc²) first derived by Einstein in 1905.
At some point in about 4 billion years, the sun’s compliment of hydrogen will drop below 12% of its original value and the process will cease; the sun will contract, heat up, expand to become a Red-giant star, subsequently stabilize and begin to use Helium as a nuclear fuel, the Helium synthesized as the by-product of Hydrogen fusion reactions over the intervening eons of time since it began to burn bright in space. This Helium fusion cycle will produce Carbon and Oxygen with the sun ending its life here as a white-dwarf star.
The sun is small and low in mass by comparison to larger, more massive stars and thus, the sequence of nuclear burning cycles ends with Helium burning. In more massive stars, it continues up the chain and stops with the Silicon burning cycle for the more massive stars. The Silicon cycle lasts only 24 hours and produces heavier and heavier nuclei up to and including Iron and Nickel. Due to the endothermic nature of Iron, all nuclear fusion cycles end here, the star collapses, internally rebounds and is obliterated in a Type-II Supernova explosion.
So what about the rest of the periodic table, how are the rest of the elements formed? All nuclei beyond Iron and Nickel up to and including Uranium are formed in the cataclysmic aftermath of a supernova in a process known as “Rapid Neutron Capture” with the Uranium nucleus the heaviest of the naturally occurring atomic nuclei. Plutonium is synthesized in a nuclear reactor using the relatively unstable isotope of Uranium, U-238. All elements heavier than Uranium are synthesized in a laboratory or reactor setting.
In the case of Uranium, the energy that binds the nucleus of this atom together originated in the furious stellar hurricane following the cataclysmic and spectacular end to a high-mass star, a Type-II supernova. It needs to be pointed out that this mass-energy equivalence, this “binding energy” of atomic nuclei, was first posited in 1905 by Albert Einstein as a minor footnote in his famous Special Theory of Relativity.
The Szilárd petition, drafted and circulated in July 1945 by Leo Szilard, a colleague and younger contemporary of Albert Einstein was signed by 70 scientists working on the Manhattan Project. The petition asked President Truman to inform Japan of the terms of surrender demanded by the allies and allow Japan to either accept or refuse these terms before the United States used atomic weapons. The petition never made it up the chain of command to Truman and wasn’t declassified and made public until 1961.
In 1946, following those fateful days in August 1945 when Hiroshima and Nagasaki were incinerated in an instant with the first-and-only use of atomic weapons, Szilard jointly with Einstein, created the Emergency Committee of Atomic Scientists that counted among its board, Linus Pauling, recipient of the 1962 Nobel Peace Prize.
The Uranium used as fissile material in “Little Boy” (Hiroshima) and the Plutonium, produced from U-238, used in “Fat Man” (Nagasaki) had their origins in the furious maelstrom following a supernova 5 billion years ago. The energy released during that supernova was hence released 5 billion years later on hundreds of thousands of innocent human beings, incinerating them and two cities in an instant. These weapons, although terrible in their own right, are mere flickers of light when compared to the nuclear weapons available today. The horror of these weapons cannot be overstated, the horror largely derived from the origin of the energy so released on living beings, the “binding energy” of these heavy nuclei, locked up for 5 billion years, released by splitting them in an atomic weapon; it is nothing short of pure evil to unleash such energy, the energy of a supernova, on a human population.
The Doomsday Clock was
founded in 1945 by University of Chicago scientists who had helped develop the first atomic weapons in the Manhattan Project, the Bulletin of the Atomic Scientists created the Doomsday Clock two years later, using the imagery of apocalypse (midnight) and the contemporary idiom of nuclear explosion (countdown to zero) to convey threats to humanity and the planet. The decision to move (or to leave in place) the minute hand of the Doomsday Clock is made every year by the Bulletin’s Science and Security Board in consultation with its Board of Sponsors, which includes 13 Nobel laureates. The Clock has become a universally recognized indicator of the world’s vulnerability to catastrophe from nuclear weapons, climate change, and disruptive technologies in other domains.
It is now 100 seconds to midnight; if the clock strikes midnight, we’re all dead.
From their 23 January, 2020 Announcement, the consortium states
Humanity continues to face two simultaneous existential dangers—nuclear war and climate change—that are compounded by a threat multiplier, cyber-enabled information warfare, that undercuts society’s ability to respond. The international security situation is dire, not just because these threats exist, but because world leaders have allowed the international political infrastructure for managing them to erode (emphasis added by this author).
Said as simply as possible, these weapons, some of which are in the hands of unpredictable, petulant and often impulsive world leaders, combined with the complicit silence and ambivalence by many to the unfolding climate catastrophe along with the open hostility by some towards science, pose a real, existential threat to our planet and our species.
Two Suns in the Sunset
Roger Waters, as songwriter for Pink Floyd’s 1983 hit release, Two Suns in the Sunset, speaks of a double sun at sunset. Clearly, there is only one sun, so what must the other sun be? If we take a look at the lyrics, what the second sun represents becomes clear:
In my rear view mirror the sun is going down
Sinking behind bridges in the road
And I think of all the good things
That we have left undone
And I suffer premonitions
Of the holocaust to come.The wire that holds the cork
That keeps the anger in
And suddenly it’s day again.
The sun is in the east
Even though the day is done.
Two suns in the sunset
Could be the human race is run.Like the moment when the brakes lock
And you slide towards the big truck
You stretch the frozen moments with your fear.
And you’ll never hear their voices
And you’ll never see their faces
You have no recourse to the law anymore.And as the windshield melts
My tears evaporate
Leaving only charcoal to defend.
Finally I understand the feelings of the few.
Ashes and diamonds
Foe and friend
We were all equal in the end.“And now the weather. Tomorrow will be cloudy with scattered showers
Spreading from the east with an expected high of 4000 degrees Celsius“
Roger was clearly referring to the brilliant mushroom cloud rising from the detonation of a nuclear weapon. In the opening frames of the following video, Roger notes that the Doomsday Clock has now been set at 100 seconds.
The Drake Equation
In 1961, the Astronomer Frank Drake, fascinated with the possibility of advanced intelligent life beyond our small corner of the galaxy, derived what came to be known as “The Drake Equation”.
N = R ∗ ⋅ f p ⋅ n e ⋅ f l ⋅ f i ⋅ f c ⋅ L
where N = the number of civilizations in our galaxy with which communication might be possible
R∗ = the average rate of star formation in our galaxy
fp = the fraction of those stars that have planets
ne = the average number of planets that can potentially support life per star that has planets
fl = the fraction of planets that could support life that actually develop life at some point
fi = the fraction of planets with life that actually go on to develop intelligent life (civilizations)
fc = the fraction of civilizations that develop a technology that releases detectable signs of their existence into space
L = the length of time for which such civilizations release detectable signals into space.
In a recently published study, that number N, has now been determined to be 36; in the simplest possible terms, according to the study, there are 36 civilizations, including our own, that have the capability to communicate with an audience beyond their host star and planetary system. With our Doomsday clock now set to 100 seconds before midnight, it remains to be seen if this number will soon change to 35.
The Fermi Paradox
Although he was not the first to consider this question, the name of famous Italian physicist, Enrico Fermi, is associated with this seeming paradox, an association arising from a casual lunch-time conversation in the summer of 1950 with fellow physicists Edward Teller, Herbert York and Emil Konopinski. While walking to lunch, the men discussed recent UFO reports and the possibility of superluminal (faster-than-light) travel. The conversation moved on to other topics until, during lunch, Fermi allegedly quipped “Where is everybody?” (there is an uncertainty regarding this exact quote).
Although Fermi and many others have since pondered this question, it wasn’t until 1961, the Drake Equation, along with advancements in radio and optical astronomy, did real data begin to emerge and inform a meaningful and, perhaps, realistic number. Fermi’s question remains, however: “Where are they?”
In a galaxy the size of the Milky Way, 36 civilizations is a vanishingly small number and, if accurate, no physical contact could be possible if the alien technology is beyond 100 years of our own and would, most likely, be unrecognizable. Radio communication would be the only feasible method of contact and, considering the distance to the nearest star system to ours, the Alpha Centauri system, a simple two-way dialog would take 8.6 years.
The larger and more compelling question is “what happens to a civilization as it evolves beyond the point where extra-planetary communications are possible?” This communications technology presupposes the development of other technologies concurrently and in parallel (truly sustainable energy generation such as nuclear fusion, transportation, computer, defense, etc). At some point, does a civilization self-destruct, do they commit suicide, are they capable of controlling base, self-destructive impulses (war, regional or global domination, greed, etc) and thus, survive to the point where extra-planetary colonies and outposts are attained and sustainable? Can we finally learn to co-exist with our neighbors? If so, and we do survive the next 50 years, this would be the first step for our species to move off Terra Firma and begin our migration towards the stars.
Are we now at that point, the point when our time runs out, the point suggested by the 100-seconds-to-midnight nightmare scenario? Are we watching the answer to Fermi’s question unfold in slow-motion before our eyes, helpless to halt the suicide? Is this why we haven’t been visited? No civilizations survive to the point where they could travel beyond their own star system. Do advanced civilizations almost always self-destruct? Will we be able to stop ourselves from committing global suicide?
Albert Einstein is credited as having made the following comment (or something similar)
“I do not know with what weapons World War III will be fought, but World War IV will be fought with sticks and stones.”
That the Doomsday Clock exists and that I’m writing this article gives us cause to hope, that there are those who care enough about the long-term survival of our planet and the human species to sound the alarm and push for constructive change. Will that be enough? Only time will tell.
James Daly, Ph.D