The Search for Advanced Civilizations in the Universe
In the film Contact, Radio-astronomer Dr. Ellie Arroway receives a message from the Vega star system which is 26 light years away from Earth. When she deciphers the message, she discovers plans detailing how to build a complex machine that will enable a single occupant to travel through space. Convinced that an alien civilization has provided her with the means to communicate with them, she obtains funding from a dying billionaire and builds the machine that then takes her through a series of wormholes to a remote planet. There she meets an alien who takes the form of her father. The alien explains that it has taken this form to make their first contact easier, and that her journey is humanity’s first step in joining other, more advanced civilizations.
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I love movies. Not only for their entertainment value but for their ability to open our minds to new worlds and new possibilities. The film Contact is one of my favorites. As a high school teacher, I screened it every year for my advanced physics classes. The students enjoyed debating the likelihood of other civilizations existing in our galaxy. Around that time astronomers were discovering many earthlike planets in the Milky Way, and the probability of the existence of other civilizations with advanced intelligence became more believable. We now know that billions of potentially habitable “exoplanets” exist, but the distances from all but the closest ones will keep us separated until we are able to travel faster than light. Or until we become a more advanced planetary civilization.
The Search for Extraterrestrial Intelligence
SETI is the acronym for “Search for Extraterrestrial Intelligence,” a project started in 1960 by Cornell University astronomer Frank Drake. Its purpose is to search for signs of life in distant planetary systems via interstellar radio waves.
Drake used a radio telescope to examine Tau Ceti and Epsilon Eridani, nearby sun-like stars that he thought were likely to have inhabited planets. The receiver was tuned to wavelengths of radiation emitted naturally by interstellar hydrogen. The investigators believed that this radiation would act as a universal standard to any advanced civilization attempting interstellar radio communication. At that time, they did not pick up any radio signals from outer space that could not be explained by natural processes.
SETI has evolved in the past six decades. We now know that there are millions of planets in our own Galaxy. NASA scientists have discovered about 4,000 of these “exoplanets.” Researchers have widened their search to include techno signatures, signs of alien intelligence consisting of laser pulses, chemical changes in a planet’s atmosphere, and even megastructures orbiting a planet or star. Some exoplanets may have conditions suitable for life as we know it. On some of these habitable worlds, life may have evolved to the point where it produces a technological civilization. Scientists use powerful telescopes to look for biosignatures in the atmospheres of exoplanets. These signatures could be the presence of a gas, such as nitrogen dioxide (NO2), the byproduct of an industrial process that we consider a pollutant.
Many astronomers currently believe that any advanced civilizations existing in the universe would be likely to reach out across space to contact other civilizations such as our own. In the past 60 years astronomers have detected only a few signals from the stars that could have come from alien civilizations. These occurrences did not repeat and were judged to have arisen from natural causes.
Types of Planetary Civilizations
The Kardashev Scale, developed in 1964 by the Soviet astronomer Nikolai Kardashev, is a method of measuring a civilization’s level of development based on the amount of energy it can use and the sophistication of its technology. He proposed three levels, which other scientists later updated to six. He theorized that a civilization’s technical advancement runs parallel to the amount of energy that the civilization is able to harness and manipulate. Essentially, the more energy that a society produces, the more technologically advanced they become.
We are a Type O Civilization. We derive energy from organic-based sources such as wood, and from fossil sources such as coal and oil. As these fuels are burned over centuries, they eventually cause the temperature of the atmosphere and oceans to rise. This global warming disrupts the weather, causing seas to flood low-lying land masses, making them uninhabitable. The coastline of every country changes. In North America, low-lying coastal cities and some states from New England to Florida will disappear under the waves. The warmer atmosphere creates droughts and firestorms that destroy farmlands and living spaces. Air pollution increases and causes millions of deaths. A large fraction of the planet’s human population must relocate for food and safety. Many species lose their habitats and become extinct.
We are beginning to experience some of these tragic events.
Our civilization has a handful of technologies to produce electric power. In 1820, Michael Faraday and Joseph Henry invented a primitive electric motor. In 1831, scientists discovered that an electric current can be produced in a wire moving near a magnet. The machine that does this is called a generator.
Type O civilizations produce electricity by turning a copper coil in a magnetic field. There are a few ways to turn the coil. Dams use the energy of falling water to turn large coils mounted around strong magnets to produce electricity. We named this process “hydroelectricity.” We eventually learned how to utilize nuclear reactions to boil water and use the resulting steam to turn a coil and generate electricity. When we mastered this technology, we built nuclear power plants to augment or replace fossil-fuel with hydroelectric power plants. For time to time these plants leak and release radioactive liquids or gases, poisoning their surroundings as in the Chernobyl accident on 1986 and the Fukushima disaster in 2011.
In the 1950s we discovered how to use solar panels to convert sunlight directly into electricity. We also learned how to utilize wind and tidal energy to produce electricity. But on a much smaller scale.
Our Type O Civilization has also tried to solve the technical challenge of taming a fusion reactor to produce energy by the same process that stars such as our Sun utilize. So far, we have not succeeded.
We are able to send chemical-driven rockets to its moon and nearby planets, but at great cost. Our rockets are driven by chemical propulsion. Since chemical fueled rockets are slow and inefficient, our civilization is presently confined to our home planet.
Type I Civilizations can harness all the energy that falls on a planet from its parent star. For the Earth, this amounts to 17,400,000,000,000,000 (10E17 watts.) We currently capture and consume about 1/10,0000 of that amount.
The string theorist Michio Kaku believes that if humanity can increase our energy production at an average rate of 3 percent each year, we may attain Type I status in 100–200 years, Type II status in a few thousand years, and Type III status in 100,000 to a million years. Other scientists believe that we have the possibility of achieving Type I status by 2050. This would require us to control global warming and develop technologies to utilize other energy sources on our planet including volcanic, tectonic, wind and tidal energy.
Type II Civilizations, also called stellar civilizations, can capture all the radiant energy that their star produces. They are planetary-wide civilizations and are likely to use Dyson spheres to collect the total energy emitted by their stars. Freeman Dyson, a futurist and astronomer conceived this idea in 1960.
Imagine a sphere around the sun with a 93-million-mile radius. Our sun emits 10E26 watts, about a billion times more energy than falls on the Earth. Now visualize the Earth on the surface of that sphere. From the sun’s perspective, we are an infinitesimal, almost invisible speck. When we can capture all the energy falling on the Dyson sphere, we will become a Type II civilization.
Type III Civilizations, also called galactic civilizations, can control energy produced by their entire host galaxy. Our galaxy, which we call the Milky Way, contains about 200 billion stars. Astronomers estimate that the Milky Way galaxy produces about 1037 watts, about 10,000,000,000 times the energy production of our sun.
Some scientists conjecture that Types IV, V, and V1 might also exist. Type IV civilizations can control the energy produced in the entire universe. Type V and VI might control the energy from the multiverse (if it exists.)
To Perish or Prevail
I am now 81 years old and will probably die before 2050 in a Type 0 civilization. However, my children and grandchildren may live far beyond that date and experience the benefits of a Type I Civilization. Let’s hope so. Humanity is presently in a do-or-die situation. If we remain a Type 0 civilization we will slowly and inexorably perish. The better choice is to get smarter by marshaling our resources, intellect and will to save our civilization and achieve Type I status.
Or perhaps an advanced civilization will reach out as in the film Contact and show us how to break out of our Type 0 prison. It could always happen, but I wouldn’t hold my breath waiting.
