Jeffrey Cavanaugh
Last week, lost amidst the tragedy and drama unfolding in Boston, Mass., science reminded us once again of the infinite smallness of human events taking place here on planet Earth.
Astronomers sifting through data collected by the Kepler Space Observatory — a telescope lofted into orbit in March 2009 with the mission of detecting Earth-like planets circling far-away suns — announced the discovery of two planets, both a bit bigger than our own, orbiting a star 1,200 light-years away in the northern constellation Lyra.
If the scientists’ calculations are correct, both worlds are within their star’s habitable zone – the orbital area around a star where mathematical models predict water, in its liquid form, can be found. Since liquid water is the key ingredient for life as we know it here on Earth, these two worlds, part of a five-planet system now designated as Kepler 62, are the best candidates so far detected by science to possess complex life outside our own solar system.
“Complex life” and “own solar system” are the operative phrases here because astronomers are still debating the possibility that primitive life – bacteria and the like – may yet be found on Mars, the Jovian moon Europa and the Saturnian moons Enceladus and Titan. Mars, as recent robotic missions to the red planet confirm, was once soaked in liquid water while Europa and Enceladus are ice worlds that contain liquid water oceans deep underneath their icy surfaces. Titan, while equally frigid, lacks liquid water, but it nonetheless is covered in a thick soup of primordial hydrocarbons that could also potentially give rise to life.
It is complex, multicellular life, however – insects, animals, fungi, and plants – which really fire our imagination and let us speculate about the possibility of extraterrestrial intelligence possessed by beings not unlike ourselves being somewhere “out there.” Our solar system may play host to simple life in several places, but only one place within it – Earth – has developed the full panoply of biological possibilities for a long enough period of time for nature to have produced us. If the planets circling Kepler 62 have liquid water, and if they have life, and if that life has evolved enough complexity to exhibit intelligence, then the implications are enormous.
In one fell stroke, the number of worlds playing host to complex life would triple – and our own solar system would not even contain the majority of it. Overnight, our home system’s place in the biological universe would shrink from being everything there is to, well, just a footnote in the vast menagerie of creatures that exist out there, waiting to be discovered in the infinite blackness of space. If intelligent life was discovered that would be a shock indeed – and not one our civilization is likely mature enough to handle.
Some who follow astronomy’s investigations into our universe are often saddened by the inevitable diminishment of humanity’s place in it. From being its central creations, science has continually relegated us to being a minor subplot in a larger, grander cosmic play. For those steeped in the primacy of man, his lordship over the Earth, and our special relationship with a universe-bestowing creator God, what science reveals about our true place in the universe is unwelcome news. Without our special place in the story of existence, what are we but adrift in the vastness of the void – forever doomed to a meaningless existence on a single planet circling an unimportant, yellow star?
The late, great Carl Sagan long pondered this question and penned a definitive answer to it entitled “Pale Blue Dot” – named after the title of a photo snapped of our planet by the Voyager I space probe after it completed its interplanetary scouting mission and began its long journey out of our solar system. Taken in February 1990 at a distance of nearly four billion miles, Earth is barely discernible in the photograph. It is, as Sagan pointed out, just a pale blue dot from that distance – a mere handful of pixels in a frame comprised of millions of them.
That very insignificance moved Sagan deeply – as it has many others who have looked upon that image of our home world, taken from so very far away. It is, arguably, the most important picture ever taken. If secular humanists can be said to have spiritual experiences, then Pale Blue Dot is an icon far more powerful than any hair of a prophet or knuckle bone of a saint, and Sagan’s reflections on its meaning are worthy enough to quote at length:
“From this distant vantage point, the Earth might not seem of any particular interest. But for us, it’s different. Consider again that dot. That’s here. That’s home. That’s us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives. The aggregate of our joy and suffering, thousands of confident religions, ideologies, and economic doctrines, every hunter and forager, every hero and coward, every creator and destroyer of civilization, every king and peasant, every young couple in love, every mother and father, hopeful child, inventor and explorer, every teacher of morals, every corrupt politician, every “superstar,” every “supreme leader,” every saint and sinner in the history of our species lived there – on a mote of dust suspended in a sunbeam.
The Earth is a very small stage in a vast cosmic arena. Think of the rivers of blood spilled by all those generals and emperors so that in glory and triumph they could become the momentary masters of a fraction of a dot. Think of the endless cruelties visited by the inhabitants of one corner of this pixel on the scarcely distinguishable inhabitants of some other corner. How frequent their misunderstandings, how eager they are to kill one another, how fervent their hatreds. Our posturings, our imagined self-importance, the delusion that we have some privileged position in the universe, are challenged by this point of pale light. Our planet is a lonely speck in the great enveloping cosmic dark. In our obscurity – in all this vastness – there is no hint that help will come from elsewhere to save us from ourselves.
The Earth is the only world known, so far, to harbor life. There is nowhere else, at least in the near future, to which our species could migrate. Visit, yes. Settle, not yet. Like it or not, for the moment, the Earth is where we make our stand. It has been said that astronomy is a humbling and character-building experience. There is perhaps no better demonstration of the folly of human conceits than this distant image of our tiny world. To me, it underscores our responsibility to deal more kindly with one another and to preserve and cherish the pale blue dot, the only home we’ve ever known.”
Contained in this newfound insignificance caused by a simple change of perspective is the notion that Earth, and all on it, are connected in a way more intimate than can be imagined. We are brothers and sisters not just with one another, but with all the other creatures, great and small, who also call this world home. This insignificant rock, hurtling around the sun, has given life and sustenance to all of us for so long that we are barely cognizant of both it and its inherent fragility – let alone the connection we have through it to all other living things. That, however, is beginning to change.
Many, if not all, of the astronauts that have been privileged enough to look upon Earth from space have, for instance, experienced a feeling known as the “Overview Effect.” This feeling – spiritual but not supernatural – is the feeling that all the faiths, ideologies, political borders and economic doctrines that divide so much of humanity are but petty tribal differences, differences that serve only to distract us from the basic truth that we are all in this together. From man to amoeba, we all live or die on the same, small world which is, as Sagan said, but a “mote of dust, suspended in a sunbeam.”
At first, this feeling was limited only to those who could experience it firsthand, but our growing technological sophistication has not only allowed us to take distant pictures of our own home world and detect potentially habitable planets inconceivably far away, but to broadcast said images and news instantaneously around the world. Anyone, from a doctoral student in astrophysics at Cal Tech to a peasant child in Central Asia, can look up pictures of our world, its brethren in the solar system and mosaic images of stars and galaxies of all varieties on the Internet. The same technology that brings us together economically and culturally has also, for the first time, given us physical pictures which drive home mankind’s fundamental unity in the most basic way possible. There we are, in full color, sitting in the heavens – all alone in the night.
Except for each other – which is the point Sagan was making and which we are just now, as a species, waking up to. The implications, though often lost in the earthbound events of the day, are profound. Today, even as we can take and broadcast around the world images of distant planets that may or may not be home to life, millions of human beings right here on planet Earth go without the basics – food, shelter, clean water or prospects for a better future. This basic want, in turn, gets funneled into belief systems that pit groups of human beings against one another, usually only to the benefit of a select few. It doesn’t have to be this way, and our growing understanding that we are not many, but one, is helping to discredit outdated practices and lingering cultural barbarisms that divide and subjugate us.
Abraham Lincoln once famously said that “a housed divided against itself cannot stand.” If Earth is our collective home – the house that shelters all of us – then the time will come, as inevitably as the celestial mechanics that propel us around our home star, when for human civilization to advance its members must no longer be divided against one another or the planetary bio-system we all depend on. It has to because if our civilization cannot stand due to our petty squabbling over meaningless distinctions and divisions then, as Sagan pointed out so eloquently, there will be no place to escape to and no one to help us when the walls collapse and the roof caves in.
So, the past week heralded both great and terrible news. The terrible was the reconfirmation, in the form of terrorist bombs, economic problems and ever more dismal environmental revelations, that we have not yet put aside enough of our differences and parochial interests to create the sustainable, unified, global civilization humanity so desperately needs if it is to survive. The great came in the form of two pale dots of light so far away that we do not yet possess the technology to see them that hint at the possibilities available to us if, despite ourselves, we manage to actually build one.