For generations, mankind has gazed upon the heavens and wondered, “are we alone in the universe?” Many popular films, television shows, books and every form of media today, including Star Wars, Star Trek, Doctor Who, the X-Files, Ancient Aliens, and so forth, either revolve around or are influenced by the notion of extraterrestrial life. Science Fiction writers such as Edgar Rice Burroughs, Isaac Asimov, HP Lovecraft, H.G. Wells and others brought these ideas to the general public in the last century. On the other end of the spectrum, an increasing number of individuals claim to have seen, photographed, filmed, or encountered an unidentified flying object - a UFO, and some have claimed to be involved with “alien abductions” or meetings with other beings. Pop culture is ablaze with concepts surrounding alien life. NASA famously continues its search for life, whether that may be “intelligent” life (ETIs) or microbial life. SETI listens for any signals from other beings. Many devote their entire resources, time, energy and lives to this search.
These ideas both fascinate and terrify the human mind. Since the 1970s, Christian fundamentalism has been written off extraterrestrials as “demonic” activity, but for others within the Christian tradition, the very notion of extraterrestrial life provides much food for thought and exciting possibilities. As a result, a speculative branch of theology has arisen: exotheology. Exotheology began as a thought experiment - how would Christianity or other religious traditions account for extraterrestrial life? If we discovered microbial life with absolute certainty, in what ways would that effect our anthropocentric view of the cosmos? By examining a brief history of how extraterrestrial life has been viewed throughout the Christian tradition, what insights we may gain from astrobiology, exploring the concept of panspermia and discussing the theological implications of ETIs, we may hope to broaden our view of “the Other” and explore new possibilities.
A Brief History of Exotheology
Although “exotheology” did not arise until the 1960s and 1970s, fascination with alien life is as old as the Greeks and Romans. Early Greek Atomists such as Democritus or Lucretius argued for a “plurality of worlds.” This had an influence on the Hellenistic Christians, and we find that many early Christians held that the planets in our solar system were inhabited (by angels) - later echoed in in the 1200s in Dante Alighieri’s Paradiso. In the 2nd century, the Roman satirist Lucian parodied The Odyssey in his work True History - in which a crew encounter alien life on the moon and on the sun, and in order to get there, the crew must fly in their ship. However, in the AD 750s, Pope Zachary condemned a man who was writing about a different race of human beings who lived on the moon. Yet such ideas were not always frowned upon. The French priest John Buridan (1295–1358) argued for the existence of many inhabited worlds, contending, “We hold from faith that just as God made this world, so he could make another or several worlds.”1
Many theologians and scholars prior to the Copernican Revolution - including Albertus Magnus, John Major, Leonardo da Vinci and others - accepted this idea of the plurality of worlds.2 In the 1440s, Bishop Nicholas of Cusa wrote, “we surmise that none of the other regions of stars are devoid of inhabitants.”3 He went on to write that it would not be improbable for “Life, as it exists here on earth in the form of men, animals and plants... to be found, let us suppose, in a higher form in solar and stellar regions.” Interestingly, he became a Bishop even after saying this, and the Church did not condemn him for heresy as had happened with Pope Zachary seven hundred years prior. The Bishop thus continued the idea that there was not only a plurality of worlds, but that these worlds were inhabited. Two Dominican friars, Tomasso Campanella (1568-1634) and Giordano Bruno (1548-1600), rejected the original Dominican 13th-century view that there was a single ordered world, and used passages from the Bible and early theologians to argue for a plurality of worlds.
The debate continued on during the Protestant Reformation in which it took a decidedly more naturalistic approach, such that we find natural theologians and philosophers including Immanuel Kant and Richard Bentley discussing exotheological concepts. In the 20th century, Anglican lay theologian and writer C.S. Lewis wrote his Space Trilogy (1938-1945) partly out of an interest in exotheology. In Lewis’ space trilogy, he portrays Earth as the “silent planet” (hence the first book’s title, Out of the Silent Planet). Earth is “silent” and not in communication with Mars, for example, because of mankind’s fallen nature. Thus, in the first two books, the theme surrounds the Augustinian notion of Original Sin, and the protagonist’s quest to keep these beings from corruption. A few decades later we find The Sparrow (1996) by Maria Doria Russel and its sequel, Children of God (1998), two well-known stories concerning the relationship between the Christian tradition and extraterrestrial life.
On a more theological level, the Jewish understanding of extraterrestrial life is of interest for this discussion. Rabbi Chasdai Crescas (1340-1411), after lengthy discussion, concluded that Jewish theology does not preclude the existence of life on other worlds. As slight evidence for extraterrestrial life, he cited the Talmudic idea that "God flies through 18,000 worlds" (Avoda Zara 3b). In this view, if God is overseeing these worlds, one could then infer that these worlds are inhabited. In fact, we read in Psalms 145:13, "Your kingdom is a kingdom of all worlds." Further, in the song of Deborah we read, "Cursed is Meroz... cursed are its inhabitants" (Judges 5:23). In the Jewish Talmud, it is held that Meroz is the name of a star. According to this view, when sacred Scripture states, "Cursed is Meroz... cursed are its inhabitants," it is evidence that God has other children. Also, Song of Songs 6:8 speaks of "Worlds without number," and the Jewish Tikunei Zohar (AD 1500s) states, "The stars certainly are without number. But each star is called a separate world. These are the worlds without number." The Tikunei Zohar goes on to state that every tzaddik (righteous person) will reign over a star, and thus, will have a world for themselves.4 The aforementioned 18,000 worlds would therefore have a number of stars presided over by the 18,000 tzaddikim (righteous individuals) who may be alluded to in the verse (Ezekiel 48:35), "Around Him are 18,000." There is a similar concept found in various parts of the Mormon tradition. This is speculative theology, to be sure, but interesting nonetheless and important in the development of exotheology.
A final point is worth noting. Often in discussions of science and religion, Christian scholars bring up the ancient idea of the “Two Books.” These two books are sacred Scripture and Nature, or rather, the two ways in which God primarily reveals Godself to us. Many early Christian writers held such ideas, including St. Paul (see Romans 1:20) St. Justin Martyr, St. Irenaeus, Origen of Alexandria, St. Augustine of Hippo, and later - St. Thomas Aquinas, Martin Luther, John Calvin, and John Wesley.5 In other words, natural revelation tells us about a divine creator just as sacred Scripture does, and therefore we ought to try and “read” the cosmos. This theology of the “Two Books” is also mentioned by Franciscan theologian St. Bonaventure, who holds that the “Book of Creation” should reveal to mankind important truths about our universe, the God who made it, and what creation holds. For this reason, we may now turn to the scientific field of astrobiology in an effort to “read” the Book of Creation for signs of God’s “other children.”
Astrobiology, Exotheology and Panspermia
In a recent article from April 2015, in which 100,000 galaxies were scanned by astronomers at Penn State, although there was no strong evidence of any “alien mega-civilizations,” it is noted that “50 galaxies did feature higher-than-usual levels of mid-infrared radiation. Further analysis will be required to determine if they're caused by some natural astronomic process, or if they're an indication of highly advanced extraterrestrial civilizations."6 Headlines and articles such as these are becoming increasingly common. The search for life across the universe - the field of astrobiology - has a long an interesting history. Most individuals may immediately think of NASA, and while NASA is a major player in the modern search for extraterrestrial life, there is a tradition extending back to ancient Greece. Metrodorus, an ancient Greek philosopher (and student of the Atomist Democritus) once said, "it would be strange if a single ear [of corn] grew in a large plain, although only one habitable world in the infinite." Now, if you go into a field, it is very unusual to see a single ear of corn growing, and you would expect many more. In his work, Metrodorus suggested that the same idea can be applied to habitable worlds.
During the Renaissance in the 16th century, an astronomer named Giodarno Bruno speculated about the possibility of life on other worlds. He wrote, "in space there are countless constellations, suns, and planets, we see only the suns because they give light. The planets remain invisible for they are small and dark. There are also numberless Earths circling around their suns."7 Interestingly, today we would now affirm the existence of these kind of planets - called exoplanets. As a side-note, an exoplanet is one which orbits a star in another solar system other than ours, and as of June 2015, nearly 2000 exoplanets have been discovered.8 This hearkens back to the ancient Greek theory of the “plurality of worlds.” Now, after Bruno, the invention of the telescope allowed us to then gaze into the heavens, causing speculation to increase as we could see other planets, but we could not see their atmospheres. Christian Huygens (1629-1695), famous astronomer, observed spots on Venus, Mars and Jupiter. He stated, "the taste of music with the inhabitants of Venus and Jupiter is at a high level, similar to the Frenchmen or Italians."9 Later, scientist William Herschel (1738-1822), wrote while observing the moon, "by reflecting a level on the subject I'm almost convinced that those numberless small circuses we see on the moon are the works of the Lunarians and may be called their towns."10
In the 20th century, Percival Lowell observed lines across the surface of Mars, and interpreted these to be canals built by a dying civilization trying to channel water from the polar ice caps.11 Lowell stated, "Every opposition is added to the assurance that canals are artificial, both by disclosing their peculiarities better and better and by removing generic doubts as to the planet's habitability.”12 In the 1950s and 1960s, the space age began, and so too began the possibility of sending probes to other planets. We began getting images from Mars and Venus, but became downcast when these images revealed no life. However, as our equipment got better, we began getting images such as former outflow channels on Mars which suggested that water once flowing on the surface. This peaked our curiosity, and in the 1970s, the Arecibo Dish Observatory sent the first signal out to extraterrestrial intelligence with the help of Carl Sagan and Dr. Frank Drake, who is famous for the “Drake equation” concerning the possibility of ETIs. Today, there is evidence of geysers erupting from the south pole of Saturn's moon Enceladus, throwing out water and other elements into space, including organic carbon.13 Many also believe that life lies in the ocean beneath the surface of another moon, Europa, and NASA is developing technology to drill through the ice layers to reach this ocean.
On a related note, from its beginning, NASA speculated that evidence of past intelligent life may lie somewhere in our solar system, that is, possible civilizations that no longer exist, but once did - “Though intelligent or semi-intelligent life conceivably exists elsewhere in our solar system, if intelligent extra-terrestrial life is discovered in the next twenty years, it will very probably be by radio telescope from other solar systems. Evidence of its existence might also be found in artifacts left on the moon or other planets.”14 Later, when Mariner 9 orbited Mars and revealed past Earth-like conditions there, searches for signs of past intelligent activity were conducted.15 Although further searches of evidence appear to have turned up little to nothing supporting ancient civilizations, there is a theory that life once existed on Mars, however, that life was wiped away due to a nuclear explosion. Dr. John Brandenburg famously presented this theory, in which there used to be two civilizations on Mars - the Cydonians and the Utopians. What happened to these two civilizations? He writes in his proposal, “ On Mars, the nearest Earthlike planet in the cosmos, the concentration of 129Xe in the Martian atmosphere, the evidence from 80Kr abundance of intense 1014/cm2 flux over the Northern young part of Mars, and the detected pattern of excess abundance of Uranium and Thorium on Mars surface, relative to Mars meteorites, can be explained as due to two large thermonuclear explosions on Mars in the past.” In other words, either the Martians caused their own destruction, or yet another race destroyed their civilization. This theory satisfied Dr. Brandenburg, but has been criticized as pseudo-science by others. Nevertheless, there are also other, perhaps even stranger, theories about life in our solar system, such as panspermia.
Panspermia is the hypothesis “that life exists and is distributed throughout the universe in the form of germs or spores that develop in the right environment.”16 The first known mention of the term was in the writings of the 5th century BC Greek philosopher Anaxagoras.17 Others continued to develop the hypothesis in the 1880s, and in 1974, scientists Sir Fred Hoyle and Chandra Wickramasinghe proposed that some dust in interstellar space contained carbon (i.e., organic material), which he later proved to be true.18 In a presentation on April 7, 2009, theoretical astrophysicist Stephen Hawking stated that “Life could spread from planet to planet or from stellar system to stellar system, carried on meteors.”19 Francis Crick, one of the men who discovered the double helix structure of DNA, held to the panspermia hypothesis.20 It was also made famous in part by the film recent film Prometheus, and the Ancient Aliens television show. Scientifically, could life have come to earth from outer space? In 1871, German geologist Otto Hahn believed that he found patterns on meteorites, and claimed that he had discovered fossilized ferns, corals and sponges. Unfortunately, these were merely mineral formations.21 In 1930, a bacteriologist named Charles Lipman claimed that he grew living cells from meteorites in his laboratory. He attempted to sterilize the samples first, as he knew they would be contaminated by Earth. After his work was reviewed, he learned that the bacteria was actually terrestrial in origin, and his sterilization had not been thorough enough.22 In 1961, Bartholomew Nagy and George Claus believed they had found “organized elements” of organic matter in meteorites. They later learned that this was actually oddly shaped mineral grains or pollen grains that come through the window in their laboratory. In 1996, NASA’s Johnson Center cautiously announced that they had discovered fossilized microbes in meteorite ALH84001, known to have come from Mars. Under an electron microscope, they found what appeared to be small, worm-like objects on parts of the rock. This discovery is still being debated, but many argue that this was simply an unintended contamination.23 Recently, a number of scientists have been investigating similar claims of objects found in Earth’s orbit.
In his course “Astrobiology and the Search for Extraterrestrial Life,” Professor Charles Cockell of the University of Edinburgh asked, "Can microorganisms survive in outer space? Space is characterized by extremes of radiation, freezing temperatures, dessication, and no oxygen. A few years ago, my own laboratory launched rocks into orbit, and these rocks were bolted onto the outside of the International Space Station. And we brought them back to earth a year and a half later to see whether anything had survived in space... we found a single microroganism, a gloeocapsa, which is a type of cyanobacterium, a photosynthetic micro-organism that was capable of surviving in the extreme conditions for a full year and a half. Of course, it didn't grow in space, but it did survive."24 We also find microorganisms that can tolerate high levels of radiation, that live deep in hot, underwater areas, that live in the arid deserts, and so forth. This is one of the reasons why NASA is interested in Saturn's moon, Europa, which is essentially a thick layer of ice on the surface and ocean underneath. These organisms are called extremophiles. The existence of extremophiles gives us hope for finding life, in whatever form that may be, elsewhere in our solar system. There are also theories that have been proposed of organic matter from earth having been jettisoned into space following asteroid collisions, and thus, it is actually humans who are seeding the solar system. Again, these are speculative ideas, but are helpful in a number of ways.
Now, at this point it is important to briefly comment on the relationship that the panspermia hypothesis plays directly into the ongoing debate concerning the origin of life and the book of Genesis. For many Young Earth Creationists (YECs) within Christian Fundamentalism, God created the universe in six, literal days a little over 6,000-10,000 years ago. For Theistic Evolutionists, God utilized evolutionary processes as an exciting and adventurous vehicle by which mankind was eventually brought about - much like Michelangelo creating a sculpture, but using a chisel to do so. There are other views, such as the Gap Theory, the Ruin-Reconstruction Theory, and so forth. Of course, these theological positions depend on one’s view of Genesis, and thus, the panspermia hypothesis only works within certain views. For example, in the view that God created everything through the “epic of evolution,” one would interpret Genesis in an allegorical, literary, functional or cosmogonic light. Early on in Christian history, Origen of Alexandria (AD 250s) and St. Augustine of Hippo (AD 354-430) proposed that Genesis could be interpreted in different ways other than literally. Dr. John Walton, in his book The Lost World of Genesis One, notes that in the Near East in antiquity, when the building of the temple to a specific god was completed, there was an inauguration ceremony. This was often six days, and all would rest on the seventh. Also, on the sixth day, an image of the deity would be placed in the temple. Similarly, Genesis 1 can be seen in this “functional origins” view, so that the six day creation - including the placement of the image of God onto the earth - followed by a rest on the seventh day, constitutes a literary way of portraying the cosmos as God’s universal or cosmic temple in which God dwells. In other words, we see the divine sovereign issuing commands, organizing territories, and governing the cosmic kingdom in this first chapter of Genesis.
Walton goes on to speak of Genesis 2 in this “cosmic temple” model, where Eden can be seen as “sacred space,” with Adam serving in a quasi-priestly role by taking care of and shepherding the “sacred space.” Now, Genesis 2-3 has also been viewed allegorically as representing Israel’s relationship with God - Eden is seen as the Promised Land, and yet once the individuals have been given this land, they disobey, and try to become gods themselves. They are subsequently banished (exiled - as in the Babylonian Exile of the Jews), and are thrown into different, more difficult conditions. Others take up the view of Genesis 2-3 as keeping with Wisdom literature (Proverbs, Ecclesiastes, Ben Sira, Wisdom of Solomon, etc.). In this view, it is not that God seeks to deprive man (‘adamah) of knowledge, but rather, he desires man to come to him for ultimate knowledge. But when man attempts to find knowledge on his own, without seeking God, he is attempting to become “like God,” and has lost his original innocence, therefore wrongly gaining knowledge and lacking wisdom to guide this knowledge. Now, these interpretations can be explored further elsewhere, but this cursory tangent is important in the larger context of the Christian tradition, because it asks, “how did God create?” If God created everything exactly as Genesis 1 says, then on a theological level, the panspermia hypothesis would not fit within the tradition. If, on the other hand, God took the “chaos” of pre-historic materials (cf. Genesis 1:2) and organized them to function with “order” (or “very good,” as in Genesis), then it is also possible that a Christian could see God using panspermia. Whether this is through the delivery of microbial life via an asteroid or the intentional planting of life on earth as in Francis Crick’s view, that is a separate discussion. But these kind of questions are helpful, as with anything in exotheology, because it asks the Christian tradition to be open to the creative movement of God’s Spirit in ways we may not yet have encountered or experienced yet.
“Would You Baptize an Extraterrestrial?”
For Christians, there still remains the question of the Incarnation and sin. If an extraterrestrial sinned on another, for example, would that require that God become incarnate as he did here through Christ? Would this create an infinite cycle of death and resurrection? This is the idea of “multiple incarnations,” and often comes up in exotheological discussions. In his article “The implications of the discovery of extra-terrestrial life for religion”, Lutheran theologian Ted Peters notes, “Paul Tillich might provide us with an example of an inﬂuential Protestant theologian who welcomes extra-terrestrial neighbours while afﬁrming multiple incarnations. [He writes,] ‘Our basic answer leaves the universe open for possible divine manifestations in other areas or periods of being.... Incarnation is unique for the special group in which it happens...it is not unique in the sense that other singular incarnations for other unique worlds are excluded’... Roman Catholic theologian Karl Rahner is sympathetic with the position Tillich espouses. He argues that the possibility of extra-terrestrial intelligent life ‘can today no longer be excluded’. Even though he acknowledges ‘Christ as the head of all creation’, he further speculates: ‘In view of the immutability of God in himself and the identity of the Logos with God, it cannot be proved that a multiple incarnation in different histories of salvation is absolutely unthinkable’... Wolfhart Pannenberg, in contrast to Tillich and Rahner, holds that one incarnation is enough for the entire cosmos. Because Jesus Christ is the incarnation of the divine Logos, and because the eternal Logos is the medium through which the entire creation has come into being... [therefore,] the signiﬁcance of the historical Jesus on Earth extends to the history and destiny of farthest reaches of the universe.”25
Others in speculative theology raise the question - if extraterrestrials are visiting or will visit us, could it be because of the “specialness” of humanity? If there was only one Incarnation, could they visit to come on a cosmic pilgrimage to the sacred site where God touched down? As Genesis says, human beings are made in the imago dei (image of God), but does this mean a physical image, a rational (reason-based) image, or a spiritual image? In what way is humanity the imago dei? This has been argued in theology for centuries. Perhaps the most prominent comes from St. Thomas Aquinas in the 13th century, who held that the imago dei is more of a rational, reason-based image, and that God has breathed that function into homo sapiens, as we do not find such developed cognitive functions among any other species. Yet exotheology also raises other questions. Br. Guy Consolmagno SJ, a planetary scientist for the Vatican Observatory, has written a book with another Jesuit, Paul Mueller, titled Would You Baptize an Extraterrestrial? Although Br. Guy does not believe that we have any conclusive proof of extraterrestrial life as of yet, he responds to the question, “Yes. If she asks for it.” But what if extraterrestrials are atheistic, polytheistic, pantheistic? What would this do for Christianity? Well, one can imagine it would have little effect, any more than sailing to a new land of individuals who have a different religious tradition would. Perhaps the answer to that question lies in the individual faith of a person. The question then lies in whether or not we would welcome these extraterrestrials with open arms.
In May of 2014, Pope Francis delivered a homily on acceptance and the Church not being so critical and judgmental. In order to make his point contemporary, he utilized extraterrestrials as an example of acceptance, saying, “If - for example - tomorrow an expedition of Martians came, and some of them came to us, here... Martians, right? Green, with that long nose and big ears, just like children paint them... And one says, ‘But I want to be baptized!’ What would happen? When the Lord shows us the way, who are we to say, ‘No, Lord, it is not prudent! No, let’s do it this way...’”.26 In the Franciscan tradition, St. Francis of Assisi always referred to creation as “brother” or “sister.” The Pope was making a point about acceptance using a modern example, and was not intending to form a lengthy point regarding extraterrestrial life. Yet we may see his point and further the question. Would we accept Brother Spock if he came to us? Would we welcome Sister Neytiri if she visited? Would we extend an arm to brother alien?
"We shall not cease from exploration, and the end of all our exploring will be to arrive where we started and know the place for the first time." - T.S. Eliot
Several years ago, the former Bishop of Stockholm and Swedish theologian Krister Stendahl, at a NASA program on extra-terrestrial life was asked what he thought about encountering intelligent extraterrestrial life. He stated, “It seems always great to me, when God’s world gets a little bigger and I get a somewhat more true view of my place and my smallness in that universe.”27 The Catholic theologian, John F. Haugh, noted that “Contact with ETs would provide an exceptional opportunity for theology to widen and deepen its understanding of divine creativity.”28 Indeed, the existence of extraterrestrial life - microbial, “intelligent” or otherwise - does not lessen the relationship of God to Earth and its inhabitants. In many ways, we are very anthropocentric (human-centered). As such, raising some of the questions asked by exotheology regardless of religious tradition as a thought experiment or as serious pondering also raises the question of our importance and role in the cosmos. It asks us what it means to be human. It helps us to remind ourselves that some of the minor issues we face on a day to day basis may be important for us, but are not always as big as they may seem. It helps us to look at each other as brother and sister, and encourages us to be willing to encounter new ideas. The universe is constantly unfolding with new and exciting potentialities. Considering the existence of others “out there” also forces us to accept ambiguity and mystery, something familiar to the Christian tradition, but something humans are uncomfortable with. But perhaps we may continue to tend to our own solar neighborhood, remain hopefully optimistic in our search for other “brothers and sisters,” and be willing to accept the cosmic mystery that comes with our existence in this universe - by seeking new life and new civilizations, and boldly going where no one has gone before.29
 Dick, S. J. 2000 (ed.) Many worlds: the new universe, extra-terrestrial life and the theological implications. Philadelphia, PA: Templeton Foundation Press. 29. Print.
 Lewis, James R. The Gods Have Landed: New Religions from Other Worlds. Albany: State University of New York Press, 1995. 191. Print
 De docta Ignoratia.
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 Nadeau, Barbie Latza. "Pope Francis Asked ‘Would You Baptize an Alien?’ Here’s the Answer." The Daily Beast. Newsweek/Daily Beast, 26 Sept. 2014. Web. 4 July 2015.
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 The opening line of Star Trek: The Next Generation, “Space: the final frontier. These are the voyages of the starship Enterprise. Its continuing mission: to explore strange new worlds, to seek out new life and new civilizations, to boldly go where no one has gone before.” The phrase “where no man has gone before” is derived from a NASA booklet, Introduction to Outer Space, from 1958.