As the world steps into the year 2022, it appears that there are still a lot of uncertainties brought about by the COVID-19 pandemic and geopolitical disputes. What differences will there be between people's expectations for the future and those in the past? Before answering this question, let us look at the world we live in from a different perspective.
On February 14, 1990, the unmanned outer solar system space probe Voyager 1 launched by NASA looked back at the earth and the solar system from a distance of 6.4 billion kilometers. The Earth appeared to be suspended in the dark background of the solar system in photographs taken at the time. In the photo, our own planet Earth is merely a tiny pale blue dot of 0.12 pixels.
This photo has also inspired the renowned astrophysicist Carl Sagan to write the book Pale Blue Dot. In the book, Sagan wrote that “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”.
Looking at the universe, Sagan sees arrogance and the folly of humanity, “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”.
Sagan's reflection triggered by the "pale blue dot" embodies a new vision, that is to look at the Earth and its human society from a cosmic perspective. This is a new view of the world that is different from the past, where things are looked from the standpoint of state and nation. Perhaps in the eyes of politicians and economists, such a vision of the astrophysicist is naïve and detached from reality, simply because it does nothing to change the human world and solve the various "real problems" that exist on Earth. However, our very own worldviews, values, and meanings are tied to how we see our problems. If we look at the world from a larger system, cosmologically speaking, we will find that Sagan’s views are closer to "the reality of the universe". In comparison, many of the things that human society cares about, its interests, concerns, and rivalry, are insignificant.
From the cosmic perspective, human beings are limited and finite. On this blue planet with a diameter of about 12,742 kilometers and a surface area of about 510 million square kilometers, it took billions of years of evolutions for an inorganic world to change to an organic one, and from single-celled life to the Earth's biosphere that is full of diversity. The emergence of human beings is accidental. In the vast universe, planets that fulfill conditions for the existence of suitable life similar to the earth are very scarce. A planet like this should be a moderate distance away from a star that is in its prime to sustain suitable temperature; having the right mass to maintain the atmosphere. It should also possess ferrous core to form magnetic field that protects life. In addition, the surface temperature should also be relatively stable in the range of -90°C to 60°C (most areas are above 0°C), for the retention of a large amount of liquid water. Humanity should be grateful that our planet meets all of these requirements at the same time.
The living beings, including humans, that were born in a corner of the Milky Way are nothing short of extraordinary existence, but they are also on the verge of extinction with the limitations on earth. With the acceleration of humankind's accumulation of knowledge and technological progress in the last 5,000 years, from the development of the writing system to the digital age, our abilities for learning, thinking, and imagination have expanded beyond the confines of our living environment into deep space. However, given current human technology and factors such as physical distance, energy level, technical restrictions, and biological characteristics, humanity's imprint may never exceed our solar system's. Take the distance of space, for example. The gravitational range of the solar system is about two light-years, which means that if a person starts a journey from Earth, and if we do not put human lifespan into consideration, based on the current flight speed, we will need at least 50,000-60,000 years to get to the edge of the solar system. Even the nearest star, Proxima Centauri, is 4.2 light-years away, and at our travel speed, it will take 130,000 years or more to reach it. With this, the idea of interstellar travel may remain a fantasy forever.
The universe taught us that we should pay more attention to ourselves: if human beings can never leave the planet where we were born, how should we treat the Earth where we live? How should we treat other fellow humans, who are the same biological species? These seemingly lofty questions will become more meaningful after we understand the fate of humanity in the universe. The Earth is indeed a small village and all human beings form a common community with a shared future. Various extreme behaviors in human development, such as excessive reproduction of human population that goes beyond the carrying capacity of the Earth's resources, nuclear wars that can destroy entire countries, industrialization regardless of environmental costs, destruction of the atmospheric balance that causes serious greenhouse effects, hatred and wars in various countries for having different ideas and values, etc., all these actions are nothing but self-destruction and self-harm.
On January 15, 2022, the violent eruption of the Hunga Tonga-Hunga Ha'apai submarine volcano in Tonga, an island country in the South Pacific, showed humanity the huge impact of natural disasters on a global scale. This may be the largest volcanic eruption in the world in 30 years, the ash column is about 5 kilometers in diameter and 20 kilometers high. The volcanic ash cloud broke through the tropopause of the atmosphere and formed an umbrella-shaped cloud cluster with a diameter of nearly 500 kilometers. Two hours after the eruption, the ashes expanded into a cloud of nearly 800 kilometers in diameter. The eruption triggered a transoceanic tsunami that affected the entire Pacific coast. It is estimated that the energy released by the volcanic eruption is equivalent to about 1,000 Hiroshima atomic bombs. Thirty years ago in 1991, the eruption of Mount Pinatubo in the Philippines affected global temperatures, emitting large quantities of sulfur dioxide, and in the following year, global temperatures dropped by nearly 0.5 degrees Celsius. Some meteorologists estimate that the impact of the Tonga volcanic eruption on the climate is about 1/50 of that of the Pinatubo eruption, that is, the average cooling is about 0.01 degrees Celsius.
The Tonga volcanic eruption shows that it does not take much effort to cause global damage to the Earth's environment and with today's human technology and destructive powers, it can happen easily. As a result, we may need to look beyond national borders, races, ideologies, economics, and technology to find more elements that have a common destiny on this light blue dot in the universe that we call home. To maintain a sustainable environment, we must modify the way we think and act to preserve the ecosystem in which we all live.
Final analysis conclusion:
In cosmic sense, the Earth is merely a "pale blue dot", and from the perspective of planetary evolution, human’s existence is but a short moment in the long river of history. Although this vision of the universe does not solve the problems of the human world, it can let us see the world differently. It allows us to realize the limitations of ethnic conflicts, racial hatred, national rivalries, and geopolitical games. If politicians in power of various countries possess such a world view, they might produce more rational public policies.
