God and Nature Fall 2019
Are We Alone in the Universe?
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By Kenell J Touryan
For the past four decades, astronomers have been listening for possible signals from outer space using radio telescopes. One of the most recent SETI (Search for Extraterrestrial Intelligence) (1) efforts is the ATA (Allen Telescope Array) in northern California, which is able to scan large areas of sky covering a wide range of radio frequencies simultaneously.
As of 2019, the Kepler space mission, a more recent space probe called TESS (Transiting Exoplanet Survey Satellite), and ground-based telescopes have discovered 4000+ planets around stars in the vicinity of our solar system (most within 100 light years from Earth) (2). Among them are earth-like planets that are within the habitable zone of their parent star. This has re-kindled a global interest in the possibility of life outside our solar system, especially as we explore the atmospheric composition of some of these planets and look for oxygen and methane that may indicate biological activity (3).
For the past four decades, astronomers have been listening for possible signals from outer space using radio telescopes. One of the most recent SETI (Search for Extraterrestrial Intelligence) (1) efforts is the ATA (Allen Telescope Array) in northern California, which is able to scan large areas of sky covering a wide range of radio frequencies simultaneously.
As of 2019, the Kepler space mission, a more recent space probe called TESS (Transiting Exoplanet Survey Satellite), and ground-based telescopes have discovered 4000+ planets around stars in the vicinity of our solar system (most within 100 light years from Earth) (2). Among them are earth-like planets that are within the habitable zone of their parent star. This has re-kindled a global interest in the possibility of life outside our solar system, especially as we explore the atmospheric composition of some of these planets and look for oxygen and methane that may indicate biological activity (3).
"...we know one thing for certain: the Creator of the universe chose Planet Earth and made a 'soft landing' in Bethlehem in the person of His Son Jesus Christ..." |
Scientists are divided regarding the issue of extraterrestrial life (4,5). Earth is full of life, including sentient life, but it is the only such planet in the universe that we know about. We often hear that, based on statistical considerations alone, there must be other life forms on some of the trillions of planets in the universe.
Vast distances, even between our solar system and its nearest neighbor 4.3 light years away, Alpha Centauri, makes detection of signs of life difficult. Unless we on Earth receive clear signals from alien life sources, this issue cannot be settled conclusively. Even if we do receive such signals from a vast universe, distance makes a timely response to them impossible. For example, the Milky Way Galaxy is about 100,000 light years across. The large Andromeda galaxy, our nearest neighbor with similar features to the Milky Way galaxy, is 2 million light years away!
To date, NASA's exploration of our own solar system has found no life outside planet Earth, either unicellular or more advanced. The next logical place to look for life is among the many planets discovered by Kepler. So far, these efforts have not yielded positive results because we have not searched with instruments capable of detecting advanced life.
Another way to address the question of extraterrestrial life is to select key criteria required to allow for life—and then sentient life—to emerge. Among these criteria is the presence of carbon, which is critical for life. Theoretical chemists list a number of reasons for this. With its four valences, carbon is capable of forming long chains and attaching other key elements like hydrogen, oxygen, potassium, and sulfur. Carbon's ability to form long carbon-to-carbon chains is one reason that there can be so many different carbon compounds. Furthermore, carbon atoms can bind to each other not only in straight chains, but in complex branches as well. They can even join "head-to-tail" to make rings of carbon atoms. There is practically no limit to the number or complexity of different molecules that can be formed by carbon, ranging from basic amino acids to more complex proteins and other biopolymers.
Imaginative scientists have conceived of various alternative chemistries for life, such as life based on the element silicon (Si). There is extensive literature on this possibility. However, silicon tends to be more reactive than carbon and less capable of forming stable, long-chained structures.
Astrophysicists have presented many conditions that would be necessary to make a planet habitable for sentient beings (6). These conditions restrict the number of earth-like planets that are hospitable for life. The first effort to demonstrate this was done by Frank Drake of Cornell University in the 60s. Drake developed a thought-provoking equation to estimate how many civilizations could exist in our galaxy. The equation was later expanded by Ward and Brownlee in their book Rare Earth (7) to include a greater number of criteria that must be satisfied for life as we know it to exist. With these added parameters, the number of planets with life becomes smaller. Ward and Brownlee caution the reader that many of the terms in their equation are known in only the “sketchiest detail.”
There are many variants of the Drake equation, and different authors have used various values for the unknown parameters. Many new factors may become known that could shift the argument for the existence of sentient beings in one direction or another. For example, whether or not oxygen and methane are found in the atmospheres of nearby exoplanets will add a great deal to our knowledge of biological activity in these worlds.
Decades of listening for signals through SETI, at a cost of millions of dollars, have so far produced no results. Some proposed reasons for the apparent silence are as follows:
Some have speculated that aliens have visited us in the past and left traces—see, for example, Chariots of the Gods by Erich von Däniken (8), and the counterargument in Crash go the Chariots by Clifford Wilson (9).
To summarize: to date there have been no credible communications that signal the existence of extraterrestrials. Distances of light years between us and even the closest planetary systems prohibit travel through galactic space with our known technologies. The many necessary conditions needed for sentient life, as listed by Ward and Brownlee, make the possibility of sentient life elsewhere in the universe low.
What then does Scripture tell us? It speaks of physical life on earth and about another world, God’s realm, very real but mostly unseen by humans. It also indicates that the source of the visible world is the invisible world (Hebrews 11:3). Although it makes no mention of life in other parts of the physical creation, it speaks of heaven, full of creatures called angels, who are messengers sent to communicate with humans on earth.
Finally, I note that God created the universe, and it is within His power to have created sentient beings on other planets, although perhaps without them falling into disobedience. This possibility was explored by C.S. Lewis in his Space Trilogy novels Perelandra and Out of the Silent Planet.
As Christians who take the Gospel seriously, we know one thing for certain: the Creator of the universe chose Planet Earth and made a 'soft landing' in Bethlehem in the person of His Son Jesus Christ to bring all humankind abundant life.
For a more comprehensive article, contact Ken Touryan at: [email protected].
References
1. Sarah Scoles (2018) Making Contact: Jill Tarter and the Search for Extraterrestrial Intelligence. Pegasus Books.
2. James F. Kasting (2018) "Habitable Planets: What are We Learning from Kepler and Ground Based Searches?" Astrobiology, 11, 2011,363-366.
3. P. Marques-Neda, et.al., National Astronomy.
4. Maria Cruz and Robert Coontz (2013) "Alien Worlds Galore." Science 340,2565-581.
5. Marcon Huerta "Is anyone out there?" (2016) Science 354,424.
6. Hugh Ross (2016) Improbable Planet. Baker Books, Grand Rapids.
7. Peter Ward and Donald Brownlee Rare Earth. Copernicus, 2000.
8. Eric von Däniken Chariots of the Gods. Corgo Books, 1972.
9. Clifford Wilson Crash go the Chariots. Lancer Books, NY.1972.
Kenell (Ken) Touryan retired from the National Renewable Energy laboratory in 2007 as chief technology analyst. He spent the next eight years as visiting professor at the American University of Armenia (an affiliate of UC Berkeley). He received his PhD in Mechanical and Aeronautical Sciences from Princeton University with a minor in Physics. His first 16 years were spent at Sandia National Laboratories as Manager of R&D projects in various defense and advanced energy systems. He has published some 95 papers in refereed journals, authored three books, and co-owns several patents.
Vast distances, even between our solar system and its nearest neighbor 4.3 light years away, Alpha Centauri, makes detection of signs of life difficult. Unless we on Earth receive clear signals from alien life sources, this issue cannot be settled conclusively. Even if we do receive such signals from a vast universe, distance makes a timely response to them impossible. For example, the Milky Way Galaxy is about 100,000 light years across. The large Andromeda galaxy, our nearest neighbor with similar features to the Milky Way galaxy, is 2 million light years away!
To date, NASA's exploration of our own solar system has found no life outside planet Earth, either unicellular or more advanced. The next logical place to look for life is among the many planets discovered by Kepler. So far, these efforts have not yielded positive results because we have not searched with instruments capable of detecting advanced life.
Another way to address the question of extraterrestrial life is to select key criteria required to allow for life—and then sentient life—to emerge. Among these criteria is the presence of carbon, which is critical for life. Theoretical chemists list a number of reasons for this. With its four valences, carbon is capable of forming long chains and attaching other key elements like hydrogen, oxygen, potassium, and sulfur. Carbon's ability to form long carbon-to-carbon chains is one reason that there can be so many different carbon compounds. Furthermore, carbon atoms can bind to each other not only in straight chains, but in complex branches as well. They can even join "head-to-tail" to make rings of carbon atoms. There is practically no limit to the number or complexity of different molecules that can be formed by carbon, ranging from basic amino acids to more complex proteins and other biopolymers.
Imaginative scientists have conceived of various alternative chemistries for life, such as life based on the element silicon (Si). There is extensive literature on this possibility. However, silicon tends to be more reactive than carbon and less capable of forming stable, long-chained structures.
Astrophysicists have presented many conditions that would be necessary to make a planet habitable for sentient beings (6). These conditions restrict the number of earth-like planets that are hospitable for life. The first effort to demonstrate this was done by Frank Drake of Cornell University in the 60s. Drake developed a thought-provoking equation to estimate how many civilizations could exist in our galaxy. The equation was later expanded by Ward and Brownlee in their book Rare Earth (7) to include a greater number of criteria that must be satisfied for life as we know it to exist. With these added parameters, the number of planets with life becomes smaller. Ward and Brownlee caution the reader that many of the terms in their equation are known in only the “sketchiest detail.”
There are many variants of the Drake equation, and different authors have used various values for the unknown parameters. Many new factors may become known that could shift the argument for the existence of sentient beings in one direction or another. For example, whether or not oxygen and methane are found in the atmospheres of nearby exoplanets will add a great deal to our knowledge of biological activity in these worlds.
Decades of listening for signals through SETI, at a cost of millions of dollars, have so far produced no results. Some proposed reasons for the apparent silence are as follows:
- The aliens are signaling, but we do not know how to listen.
- Given the short history of our advanced civilization, we have not listened long enough, or messages sent by aliens have not reached us yet.
- The "zoo hypothesis": extraterrestrials have isolated the Earth and observe it without interfering.
Some have speculated that aliens have visited us in the past and left traces—see, for example, Chariots of the Gods by Erich von Däniken (8), and the counterargument in Crash go the Chariots by Clifford Wilson (9).
To summarize: to date there have been no credible communications that signal the existence of extraterrestrials. Distances of light years between us and even the closest planetary systems prohibit travel through galactic space with our known technologies. The many necessary conditions needed for sentient life, as listed by Ward and Brownlee, make the possibility of sentient life elsewhere in the universe low.
What then does Scripture tell us? It speaks of physical life on earth and about another world, God’s realm, very real but mostly unseen by humans. It also indicates that the source of the visible world is the invisible world (Hebrews 11:3). Although it makes no mention of life in other parts of the physical creation, it speaks of heaven, full of creatures called angels, who are messengers sent to communicate with humans on earth.
Finally, I note that God created the universe, and it is within His power to have created sentient beings on other planets, although perhaps without them falling into disobedience. This possibility was explored by C.S. Lewis in his Space Trilogy novels Perelandra and Out of the Silent Planet.
As Christians who take the Gospel seriously, we know one thing for certain: the Creator of the universe chose Planet Earth and made a 'soft landing' in Bethlehem in the person of His Son Jesus Christ to bring all humankind abundant life.
For a more comprehensive article, contact Ken Touryan at: [email protected].
References
1. Sarah Scoles (2018) Making Contact: Jill Tarter and the Search for Extraterrestrial Intelligence. Pegasus Books.
2. James F. Kasting (2018) "Habitable Planets: What are We Learning from Kepler and Ground Based Searches?" Astrobiology, 11, 2011,363-366.
3. P. Marques-Neda, et.al., National Astronomy.
4. Maria Cruz and Robert Coontz (2013) "Alien Worlds Galore." Science 340,2565-581.
5. Marcon Huerta "Is anyone out there?" (2016) Science 354,424.
6. Hugh Ross (2016) Improbable Planet. Baker Books, Grand Rapids.
7. Peter Ward and Donald Brownlee Rare Earth. Copernicus, 2000.
8. Eric von Däniken Chariots of the Gods. Corgo Books, 1972.
9. Clifford Wilson Crash go the Chariots. Lancer Books, NY.1972.
Kenell (Ken) Touryan retired from the National Renewable Energy laboratory in 2007 as chief technology analyst. He spent the next eight years as visiting professor at the American University of Armenia (an affiliate of UC Berkeley). He received his PhD in Mechanical and Aeronautical Sciences from Princeton University with a minor in Physics. His first 16 years were spent at Sandia National Laboratories as Manager of R&D projects in various defense and advanced energy systems. He has published some 95 papers in refereed journals, authored three books, and co-owns several patents.