National Catholic Register


Believe in Extraterrestrials? You’d Be Better Off Moonstruck

BY Stanley Jaki

February 15-21, 1998 Issue | Posted 2/15/98 at 2:00 PM


“Are we alone? …

Statistically, there is every likelihood that life has evolved elsewhere in the universe.” So it was claimed in the “Millennium Notebook” about “questions that stump scientists,” in Newsweek Jan. 19.

If one proposes the probability for the origin of life in the context of the question, “Are we alone?” it is right to shift the issue directly to another question: What is the probability that there are highly developed technological civilizations elsewhere in the universe?

In reality, it is very unlikely. Yet the media takes lightly—or simply ignores—eminent scientists who have expressed scorn for the idea that there are extraterrestrials able to communicate with us.

Ernst Mayr, the dean of American biologists, has said the federal funding of SETI (Search for Extraterrestrial Intelligence) was a “deplorable waste of taxpayers’ money.” He had no choice. As a consistent Darwinist he had to regard the emergence and further evolution of life as a chance process. Therefore he had to view it as most improbable that evolution would repeat itself elsewhere and produce intelligent beings similar to us.

On a purely Darwinian basis, the Nobel laureate physicist C.N. Yang hit the nail on the head when, 30 or so years ago, he suggested that we must not try to answer any radio signal from another civilization. No other attitude is reasonable from the viewpoint of Darwinian theory, which offers no exception to a remorseless struggle for life with no quarters given. It is only in Isaiah's eschatological vision that a lamb lies down with a lion and a child plays with a viper.

Lessons from the Moon

One need not be an expert in the life sciences or in nuclear physics to realize that, instead of “every likelihood,” one should talk of a probability well nigh zero. It is enough to ponder the presence of the moon around the earth and be struck by it. This presence is unique in the solar system although there are scores of moons around other planets. The mass of the moon relative to the earth, its chemical composition remarkably similar to the chemistry of the earth's mantle, the moon's apparent size, its daily and monthly influence that produce the tides (all these make the earth-moon system unique in the solar system). It is sheer science to say that we earthlings live not simply on the earth but on the earth-moon system.

Today astronomers dealing with the origin of the moon accept the unlikely scenario of a glancing collision between the earth and a hypothetical celestial body called X. This scenario contains at least five independent factors, all rather unlikely. The body X had to have a mass 10 times the mass of Mars (Factor 1). The direction (Factor 2), the velocity (Factor 3), and the plane (Factor 4) of the motion of X had to be within very narrow margins so that our moon and our earthmoon system might be the result. Moreover, the collision had to occur within a narrow range of time during the formation of the Earth itself (Factor 5)!

If one now takes the probability of each of those factors for one in 10, or 10-1, which is a most conservative estimate, their combined probability is one hundred thousandth, or 10-5. Actually, it would be more accurate to say one in a million, or 10-6, because Factor 5 can hardly be given a greater probability than one in a hundred.

Ten thousand, or 10-4, is the typical figure given by supporters of SETI as the number of technological civilizations in our galaxy. This is the figure that Frank Drake supports in his latest evaluation of the Drake equation, which he first proposed in 1961. This figure is based on first taking the number of stars similar to our sun in our galaxy. Obviously only a fraction of such stars would have a planetary system around them. Only a fraction of such systems would have an earth-like planet. Only on some of these earth-like planets would life evolve and evolve in turn into higher organisms. And only a few types of these would reach high intellectual and technological levels.

So much for the way Drake and others have reduced the figure ten billion (the number of stars in our galaxy) to a mere ten thousand. But they have invariably disregarded the unlikelihood of the earth-moon system. Had they done so, they would have arrived at 10-2, the product of 10-4 and 10-6. This would mean that the likelihood of there being a single technological civilization other than ours in our galaxy is one in a hundred. This in itself would be a far cry from “every likelihood.”

The moon played a role not only in the evolution of purely organic life through producing the tidal basins. The moon also played a crucial part in the development of man's intellectual life. Suffice it to recall Aristarchus's measurement of the relative and absolute distances among the earth, the moon, and the sun. Without this measurement there would not have been a Ptolemaic astronomy. Without Ptolemaic astronomy there would be no Copernican astronomy; and without Copernicus, no Newton.

Yet Aristarchus's feat would not have been possible if the moon's apparent diameter in historic times had not been equal to that of the sun. Without the moon being where it is, as it keeps receding from the Earth, Newton could not have convinced himself that the celestial bodies obeyed the same laws of motion as did freely falling bodies on earth. In view of this the accidental fall of an apple on young Newton's head takes on a new significance.

In other words, before one waxes enthusiastic about extraterrestrials, one should be ready to be a bit struck by what the moon means to the earth. This would have been, of course, the duty of astronomers like Drake and others who are spreading the gospel of “every likelihood.” They assume without further ado that once there is life, there is intelligence, and once there is intelligence, there is science and advanced technology.

The history of science shows exactly the opposite. Science suffered a monumental stillbirth in all great ancient cultures, such as China, India, Egypt, Babylon (and Greece as well). None of them turned out to be the matrix for the formulation of Newton's three laws, the very foundation of exact science and technology.

Of those three laws, Newton formulated only the third, the force law. The second law (action equals reaction) he borrowed from Descartes. The first, the most fundamental, the law of inertial motion, was formulated by John Buridan, more than 300 years before Newton. And he formulated it in the context of his Christian belief of creation out of nothing and in time.

Christian faith, a unique reality on earth, is, of course, inconceivable without the Incarnation, another unique event. Let us, however, consider here improbabilities unrelated to religion. Buridan might have perished in the Black Death of 1349 that claimed one-third of Europe's population and ravaged Paris too. There would be no Kepler's laws, the very foundation of Newtonian physics, if Tycho Brahe (a 16th century Danish astronomer) had lost not only his nose in a duel, but also his eyes. There would be no Newtonian system, if young Horrocks, the author of the first readable account of Kepler's laws, had died not at the age of 21 but at 18. Geniuses, let us not forget, cannot be had on order, like so many take-out lunches.

So much for some very narrow escapes for science, which had many more such escapes that would be listed in any non-triumphalistic account of the its history. Their combined improbability might easily reduce the one-hundredth probability to one-millionth, or perhaps to one-billionth, or even less. In other words, instead of talking blithely of “every likelihood,” one might say that the probability of finding at least one group of technologically accomplished extraterrestrials in our galaxy is utterly minimal on the basis of what we know and not what we may imagine in brazen disregard of the facts.

But this is not yet the whole of the advisability of letting oneself be a bit moonstruck first, before speculating about extraterrestrials. The moon, as anyone can find out with good binoculars, is pockmarked everywhere (even more so on its far side). There one of the largest craters (about 12 miles in diameter) is called Giordano Bruno. It now seems certain that it was caused by the impact of a huge comet or meteor.

Furthermore it is possible to date that event with fair certainty. It is known that the longitudinal free librations of the moon are slowing down (being dampened). Since they could not have a starting magnitude above a certain maximum value, the past history of those librations can be estimated. This work was done by the astronomer J.B. Hartung in 1976, and further refined by O. Calame and J.D. Mulholland, who utilized the data obtained by the Luna 24 mission and by laser range observation. Their conclusion was that those librations could not have started much earlier than about 800 years ago. They also pointed out that the impact of a huge meteor just beyond the edge of the moon must have started those librations and that the fiery explosion produced by the impact might have been seen from the earth.

A Medieval Record

Somehow those two astronomers learned about a strange detail in the famed Chronicles of Gervase of Canterbury, concerning the night of June 18, 1178. They quickly saw that 800 years lead one back, more or less, to that year. On that night, Gervase, the best medieval chronicler of England, and at least five others saw that “the upper horn of the New Moon suddenly split in two and from the midpoint of the division a flaming torch sprang up, spewing out fire, hot coals, and sparks to a considerable distance. Meanwhile the rest of the moon's body became, so to speak, anxiously twisted, and convulsed as if it were a snake, to use the words of those who reported this to me as something that they saw with their own eyes. After that the moon returned to its normal state. This vicissitude was shown by the moon more than a dozen times, namely, that it sustained, as if drunken, various fiery torments and returned again to its normal shape. After these vicissitudes the moon became sort of blackish from horn to horn. These things, which I am writing, those men, who saw them with their very eyes, were ready to confirm under oath, namely, that they added nothing false to the details given above” (cf. 1879 English edition, vol. 1, p. 276).

But suppose that the comet had arrived a bit later and instead of hitting the moon it had crashed into the earth. Had it hit the earth somewhere in Western Europe, it would have extinguished the nascent university system and would have snuffed out the very medieval beginnings of modern science.

Only those who are able to see the hand of Providence behind the moon's posing as a shield for the earth have nothing to fear. The immensity of outer space opening up in the 17th century frightened, as Pascal well put it, only the libertines, the “free thinkers” of his time. The terribly catastrophic character of cosmic space as it is coming into view today, should seem hopelessly terrifying only for those who have nothing to see beyond those cosmic vistas. Today they dream about extraterrestrials, because they are afraid to be alone. Rather they should be ready to be a bit moonstruck, and do so in the name not so much of religion, but of plain science. They might then even notice that, beyond science, revealed religion looms large as its saving grace.

Father Jaki, an honorary member of the Pontifical Academy of Sciences, writes from Princeton, N.J. He received the Templeton Prize in 1987 for his many writings on faith and science.