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6 It Came From Earth, Too

6 It Came From Earth, Too

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Science, Culture and the Search for Life on Other Worlds

humans were not alone in the universe and to even imagine what alien others

might look like, with their quasi-humanoid mega-craniums, bug eyes, and the

like. Not only might there be other alien civilizations, but the universe might

even be teaming with such civilizations and many of them might be significantly more technologically advanced than ours. Humanity seemed increasingly

likely to be a very small voice in a very large universe with many, many voices.

Starting with the Copernican revolution and the realization that our planet

was not at the center of anything, an interpenetrating flow of new ideas and

innovative technologies combined to lead humans, by the end of the nineteenth

century, to a point where they could fairly easily imagine other planets inhabited by intelligent species. And by the 1950s, this imaginary had intensified and

broadened significantly as it became clear that we were on the verge of developing the technologies that would allow humans to travel into space.

The implications of emergence and slow growth of the heliocentric worldview as a replacement for the geocentric one was that by the 1950s, people in

developed countries, at least, had the cultural tools to imagine aliens—they

could think about what they might look like and could ponder other planets

with beings biologically distinct from humans who built civilizations different from the terrestrial one. In what I consider one of the most fascinating

and ground-breaking science fiction films of the 1950s, we find the Krell of

Forbidden Planet, with their 30 km2 underground computer and the endearingly advanced Robbie the Robot who is really smart and seems to be able to

synthesize most anything. Forbidden Planet is important because it’s the first

film to depict humans traveling in a faster-than-light spacecraft that is a product of their own ingenuity. In a plotline that has similarities to Shakespeare’s

The Tempest, our twenty-third century descendants encounter the technology,

and only the technology, of a civilization gone for 200,000 years, but capable

of building something that can last seemingly forever, powered by the energy

of 9,200 thermonuclear reactors.

The Krell are pretty amazing, but the really amazing thing about Forbidden

Planet is that it shows just how far humans had come since the Enlightenment.

Eighteenth century thoughts about possible other worlds had evolved into

nineteenth century beliefs in a Martian civilization that by the 1950s had

morphed into the ability to imagine technologies far beyond anything humans

were capable of building. We might not be able to imagine exactly how the

Krell could build such machines, but we could imagine an alien civilization

capable of building such things.

It was in this cultural milieu that scientists in the 1950s began to ponder

the possibility of designing research projects that might generate the empirical

evidence needed to determine if extraterrestrial intelligence and civilizations

actual existed.


Science and the Emergence of SETI

Our sun is one of 100 billion stars in our galaxy. Our galaxy is one of

billions of galaxies populating the universe. It would be the height of

presumption to think we are the only living things in this enormous


—Wernher von Braun, quoted in the New York Times, 29 April 1960

At this point in our exploration, it should be fairly clear that I see the rise of

SETI as a product of the confluence of cultural and technological innovations

that developed from the Enlightenment onward and generated in Europeans,

Americans, and eventually many others, the capacity to imagine a universe

populated by non-human intelligent species with whom we might be able to

communicate. Post-Enlightenment people were not, as noted earlier in the

book, the first to think about such things. The Greeks imagined a universe in

which it seemed likely that other civilizations could exist and the follower of

Democritus, Metrodorus of Chios, in the fourth century BCE, was able to

write of an infinite universe populated with other species: “To consider the

Earth as the only populated world in infinite space is as absurd as to assert that

in an entire field sown with millet, only one grain will grow.”

But among the Greeks, these ideas were the imaginings of elites—the educated and literate—and eventually the Ptolemaic/Christian worldview derailed

their insights in such a way that it generated a different kind of imaginary in

which the idea of alien others was difficult to conceive. It was not until the

invention of technologies such as the telescope, allowing for better collection

of empirical data, and the creation of calculus as a means of mathematically

describing the universe through the work of Descartes, Newton, and Leibniz

© Springer International Publishing Switzerland 2016

J.W. Traphagan, Science, Culture and the Search for Life on Other Worlds,

DOI 10.1007/978-3-319-41745-5_3



Science, Culture and the Search for Life on Other Worlds

that cracks in the geocentric imaginary began to become gaping holes opening

a path to new ways of seeing the universe and contemplating our place in it. By

the middle of the nineteenth century technologies of mass literacy and education—newspapers, magazines, the telegraph—allowed for the emergence of

a broad imaginary in which the general public could think about and debate

the existence of intelligent extraterrestrials. And in the twentieth century,

this intensified with the invention of radio and television and much later the

Internet. Without that confluence of technological and cultural innovation—

and the corresponding generation of a new imaginary—the scientific search

for extraterrestrial intelligence that began in the second half of the nineteenth

century with astronomers like Percival Lowell and continues to the present

would not have been possible.

As discussed in the previous chapter, the ideas of Lowell (and others who followed him) about Mars were biased in many ways, perhaps most importantly

by a personal desire to observe a civilization resident on our cosmic neighbor,

and that wish for the existence of an alien civilization just around the corner powerfully influenced the manner in which data were both collected and

interpreted. By the 1920s, it had become clear that the empirical evidence for

canals and a complex water-based civilization on Mars was weak at best, even

if there remained a viable hypothesis that Martian vegetation might exist.

From the 1940s onward even the idea of vegetative life had become questioned and the notion that animal life might exist was deemed highly improbable due to the scarcity of oxygen in the atmosphere. Nonetheless, throughout

the 1950s there remained active interest in the possibility of vegetative life on

Mars among scientists, even while there were ongoing differences in opinions

about the manner in which data related to the presence of water and the

nature of the atmosphere should be understood. And the public discourse on

Mars continued to raise the possibility that their might exist in the present or

distant past a great civilization on Mars—indeed, there continue to be those

in the early twenty-first century who think that certain natural, geological

features of the planet are actually evidence of a past civilization capable of

large-scale monumental architecture.

Debates within the scientific community continued during the 1950s

about vegetation on Mars. Oddly enough, even into the twenty-first century

this idea has been raised with Arthur C. Clarke’s claim that images from the

Mars Global Surveyor show the presence of vegetation reminiscent of earthly

Banyan trees on the planet’s surface. Differences in both methodology and

worldviews influenced the extent to which scientists have been interested in

the possibility of extraterrestrial life. Some astronomers have been content

with presenting data about Mars and other locales in our solar system while


Science and the Emergence of SETI


avoiding interpretive turns in which they attempted to address the question

of extraterrestrial life, while others gathered data with the aim of answering

said question. As debates continued in the 1950s and onward, two important

technologies were becoming powerful tools to begin addressing the question

of both extraterrestrial life and extraterrestrial intelligence—space travel and

radio astronomy.


Humans Beyond Earth

In the postwar atmosphere of the US, new technologies were not only supporting the growth of an imaginary in which aliens seemed both possible and

even a potential threat (think of the UFO sightings that became common

after World War II). Technologies like television were also contributing to the

dissemination of another imaginary involving an alien other. This imaginary

was encapsulated in the scare over communism exemplified in the tactics of

Senator Joseph McCarthy. Fear and paranoia about the dangers of communism as well as the dangers of atomic power in the 1950s were evident not

only in the news media, but also many popular science fiction movies.

As Cynthia Hendershot has pointed out, the prehistoric monsters, bodyinvading pod people, Martians, giant ants, and intelligent vegetative things

from another world broadcast to audiences in movie theaters across the nation

were part of a public discourse of paranoia that expressed insecurity about

life in the face of both the Soviet threat and the potential for atomic disaster.

Interestingly, the ability of Americans to accept the possibility of life on other

worlds created a situation in which extraterrestrial aliens could be employed

to represent fears about communism and atomic annihilation, as well as to

convey the possibility that we might be saved from our stupidity by an alien

civilization that had matured past these political problems, as is evident in the

messianic figures of characters like Klaatu from The Day the Earth Stood Still.

That said, most 1950s movie aliens were of the sinister variety like in that

Peter Graves classic Killers from Space where nasty aliens want to eradicate

humanity using giant bugs and reptiles created from our own nuclear testing. And then there is that masterpiece of awfulness, 1953’s Robot Monster, in

which Ro-Man Extension XJ-2 has exterminated all but eight of the humans

on Earth with his Calcinator Death Ray—apparently even evil robot monsters

from space wearing gorilla suits and helmets have technical limitations, but

I suppose 2,665,865,384 out of 2,665,865,392 is a pretty good percentage

(0.99999999699 %).


Science, Culture and the Search for Life on Other Worlds

The pivotal point in the experience of this imaginary came in the late

1950s with the launch of Sputnik by the Soviet Union on 4 October 1957.

The Vanguard program, which was the American effort to launch a satellite

into orbit, was limping along—with many problems related to the performance and design of its rocket—and the American public was generally under

the assumption that their country would be the one to inaugurate the space

age with the first successful space trip. Americans were stunned by the fact that

the Soviets had beaten them to the punch line and shown clear evidence of

technological superiority when it came to spacecraft, a point summed up in the

cynical comment of Wernher von Braun, who lamented that Americans would

need to pass through Russian customs when they finally reached the moon.

Others have discussed the historical dimensions surrounding the launch

of Sputnik and the American response in detail—a good example is Yanek

Mieczkowski’s recent book Eisenhower’s Sputnik Moment: The Race for Space

and World Prestige—so I don’t need to expand on this topic here. Rather,

I’ll emphasize the fact that in the late 1950s it became reasonable to think

humans would eventually leave the planet and perhaps even do so in large

numbers in the not too distant future. This is not to say that everyone thought

humans would, or should, travel into space. Bob Ward, in his biography of

von Braun, notes that many Americans thought it was either impossible to go

to the Moon or somehow contrary to the Bible and, thus, against the wishes

of the Christian god for humans to depart the planet. And von Braun himself

was occasionally accused of being a nutcase due to his insistence on the idea

that humans would travel into space. But the overall attitude of Americans,

at least, was that space travel was in humanity’s future and Americans should

lead the way off the planet.

The launch of Sputnik, as well as earlier technological achievements such

as breaking the sound barrier in 1947 by Chuck Yeager in the Bell X-1, provided evidence to support the public discourse that the stars might be within

reach of humanity. It’s striking when one watches movies from this era the

extent to which Americans, at least, were unaware of the truly daunting challenges involved with space travel—rarely are the kinds of distances involved

in travel to other planets in the solar system, let alone other stars, accurately

represented, usually being vastly underestimated, with aliens arriving at Earth

from planets 10, 20, or 100 million miles away, but clearly not from our

solar system. Even in the excellent film The Day The Earth Stood Still, the

distance traveled by the alien is indicated at 250 million miles from Earth,

which would place his point of origin as somewhere in the asteroid belt

between Mars and Jupiter. However, despite the frequent lack of scientific

accuracy, the combination of science fiction stories (both in print and film)


Science and the Emergence of SETI


with the rapid flow of technological breakthroughs related to air and space

travel strengthened the idea of extraterrestrial civilizations existing somewhere

in the universe, as well as the possibility that some of those aliens might be

visiting Earth. If our toddler-like steps into the cosmos were able to happen

in such a short time—remember the Wright Brothers had flown only 53 years

earlier—then what was there to prevent a much older alien civilization from

faring into space and even visiting our planet?

While rocket scientists were pursuing new technologies that captured the

imagination of the public, a few other scientists were also thinking about

how a different technology—radio astronomy—might be used to determine

if extraterrestrial civilizations actually existed. For the most part among the

scientific community in the 1950s, the search for extraterrestrial intelligence

was not taken particularly seriously, but there had been a few attempts

earlier in the century to see if there might be radio signals from an alien

civilization floating around. From 1919 to 1922 popular publications such as

The New York Times and Scientific American—both well-respected sources for

information on science—had covered claims that none other than inventor

of the radio Guglielmo Marconi had received evidence of radio transmissions

from Mars. These claims contributed to the broad public discourse not only

about the existence of Martian civilization but also raised the possibility that

it might be possible to communicate with the Martians by using the recently

invented technology of radio telegraphy.

In the end, Marconi’s claims were discounted and little interest in the

potential for using radio-based technologies was evident until the late 1950s

when Philip Morrison and Giuseppe Cocconi, both astronomers at Cornell

University, published a paper in Nature (19 September 1959), in which they

raised the idea of searching the microwave spectrum for signals from extraterrestrial civilizations. This article is considered a cornerstone publication in the

scientific search for extraterrestrial intelligence in part because it was written

by two established astronomers working at one of the top universities in the

US. Morrison and Cocconi began with a general summary of the scientific

understanding about life on other planets as of 1959. They made the clear

point that there were no reliable theories at the time that could estimate rates

of planet formation (we do have this now), how often life arises, or how often

life evolves into intelligence and civilization.

It’s fascinating that Morrison and Cocconi take the strong position that

there is “very probably” life on Mars and use that in combination with the

obvious fact that Earth has not only spawned life, but also a civilization capable

of investigating the possibility of life on other planets, as a basis for justifying

the search for extraterrestrial life on the grounds that if the emergence of life


Science, Culture and the Search for Life on Other Worlds

happened twice on planets in such close proximity, there is a good chance that

there is plenty of other life in the universe. Morrison and Cocconi argued that

some of the societies on other planets should be very old, perhaps even old

in a sense that their age might be comparable with the geological time scale,

thus being measured in millions rather than thousands of years. Furthermore,

working from the assumption that the universe should have an abundance of

life, the authors conclude it reasonable to assume that somewhere surrounding a star similar to our Sun, there lives a civilization interested in science

that has technological abilities beyond our own. Turning their telescopic lens

backward, Morrison and Cocconi speculate that to the beings who populate

such planets our own star would appear as a probable location for the evolution of a new civilization.

From these initial assumptions and ideas, which are in fact quite speculative,

the authors detail some specifics about frequencies, bandwidth, and potential

target stars from which a radio signal might be received. When it comes to

the search for life on other worlds, brief as it is, this article became a blueprint for SETI research that continues to have influence into the present.

Unfortunately, the assumptions behind Morrison and Cocconi’s speculative

piece are not without problems.

Obviously, the fact that the likelihood of Martian life has dwindled somewhat with improved methods for observing the planet weakens the argument

for an abundance of galactic life due to empirical evidence from our cosmic

neighborhood—Earth remains the only place where we have found conclusive

evidence of life. However, at this point in time, we have no reason to believe

that ours is the only type of star that could generate a society capable of radio

transmissions and, in fact, there are a few exoplanets in habitable zones around

other stars unlike the Sun, such as Kepler-186f, which has a radius similar to

Earth’s but orbits the red dwarf Kepler-186 about 500 light-years from Earth.

Nor is it necessary to assume that a civilization with which we might come into

contact would be much older than our own, although obviously the longer a

civilization has been broadcasting, the more likely we are to intercept a broadcast. And should an alien civilization be significantly older than our own, it

might make sense to assume that they have developed technologies so different

from ours that we could not recognize their signals nor would they necessarily

notice our own feeble signs of technological emergence.

The problem we face is that all we have to go on is one planet, one fragmented

civilization, and absolutely no concrete evidence for life anywhere else. Thus, we

have no basis for comparison and no means by which to draw even tentative

conclusions about the nature of other civilizations on other planets orbiting

other stars or to even guess at the likelihood of their presence—anything we


Science and the Emergence of SETI


say that is in any way predictive about the nature of life on other worlds falls

squarely into the realm of conjecture.

This also leads us to a significant issue in much of the writing that has been

done in SETI on the possible nature of alien civilizations. The issue to which

I refer is the tendency to anthropomorphize institutions and other forms of

social organization as things with “scientific interests” rather than to recognize

that our own “civilization” on Earth is, in fact, extremely fragmented and quite

difficult to assign any interest to other than self-interest, and even that is open

to considerable question given the presence of nuclear weapons and the environmental damage we are doing to our planet. Alien civilizations are usually

imagined among SETI scientists, as well as in science fiction literature, as being

homogeneous and displaying scientific interests and general unity, despite the

fact that we have absolutely no evidence from Earth that this is a likely pattern

of social organization among unambiguously intelligent species.

Specious assumptions aside, Morrison and Cocconi end with an important comment that has become something of the mantra of SETI researchers

employ when confronted with the fact that several decades of searching has

produced nothing in the way of positive results. Morrison and Cocconi state

that while it’s difficult to estimate the probability of successfully finding an

alien radio signal, if no one searches, the chances of intercepting an alien

transmission are zero. This key point has buoyed the spirits of astronomers

engaged in SETI in the face of low odds of success and a long-term inability

to produce any empirical results supporting the idea that extraterrestrial intelligence exists. The idea also has been widely used to justify continued investment of both time and money in SETI.

Let me be clear that I don’t point out the assumptions in Morrison and

Cocconi’s article to devalue their work—it’s important and set forth an entirely

new area of scientific research. And I agree that if we don’t look, we are unlikely

to find evidence that we are not alone in the universe. But all forms of research

start with assumptions and some of the assumptions that have continued to

shape SETI are clearly evident in this germinal publication, even if they are

now open to question in the early part of the twenty-first century.


Culture and the Drake Equation

Around the same time that Morrison and Cocconi were thinking about

radio astronomy as a means to seek evidence of extraterrestrial civilizations,

another astronomer, Frank Drake, recognized the potential of the technologies of radio astronomy for revealing the existence of alien civilizations. If


Science, Culture and the Search for Life on Other Worlds

there were civilizations out there that could send out radio signals, we had the

technology in radio astronomy to potentially intercept those signals. Drake

initiated the first observational study designed to detect signals from extraterrestrial intelligence in 1960 with his Project Ozma, named after the princess

of Oz in the L. Frank Baum books. Project Ozma represents a watershed

moment in the scientific search for extraterrestrial intelligence because it

shifted our gaze from the immediate neighborhood of Earth to the much

more likely candidate for intelligent life—the galaxy at large.

After completing his Ph.D. in astronomy at Harvard, Drake took a position at the National Radio Astronomy Observatory at Green Bank, West

Virginia, where he was head of the Telescope Operations and Scientific

Services Division and conducted planetary research and cosmic radio source

studies. Drake used the National Radio Astronomy Observatory to look at

two nearby stars, Tau Ceti and Epsilon Eridani, focusing on a part of the radio

frequency spectrum near the 1420 MHz marker. A common assumption of

SETI has been that an intentional signal might be broadcast at 1420 MHz,

which is the natural marker frequency for hydrogen, the most abundant element in the universe. A reasonable assumption is that an alien intelligence

sending out a signal with the intention of it being intercepted by another

civilization might pick this frequency as it would represent evidence of intelligence because it would signal awareness of the abundance of hydrogen in

the universe and, thus, also show scientific knowledge. The particular targets

of Project Ozma were chosen because they are relatively sun-like stars and,

therefore, were seen as potentially likely to have Earth-like planets orbiting

them. After approximately 150  h of intermittent observation, and a falsepositive signal caused by a secret military facility, Drake found no evidence of

extraterrestrial technology.

The failure to produce any evidence of emissions generated by extraterrestrial technology did not deter Drake and he went on to become one of

the most prominent figures in the scientific search for extraterrestrial intelligence, while also pursuing research on pulsars and serving as Director of the

Arecibo Observatory in Puerto Rico from 1966 to 1968 and then Chair of the

Astronomy Department at Cornell for 3 years following his Aricebo assignment

(these are a few among many accomplishments over Drake’s long career).

A year after his Project Ozma experiment, Drake held the first scientific

conference dedicated to SETI, gathering together a group of prominent

researchers in the physical, biological, and social sciences. This group included

J. Peter Pearman of the National Academy of Sciences space science board,

Melvin Calvin, whose Nobel Prize was announced during the conference,

and NASA’s Shu Shu Huang, who had developed the idea of habitable zones


Science and the Emergence of SETI


around stars in 1959, as well as Morris, Coccini, and a young astronomer

named Carl Sagan. The agenda for the meeting included a wide range of

topics including stellar and planetary formation, the emergence of life, and

the existence of planets within habitable zones. It also explored themes surrounding communications technology, the evolution of intelligence, and the

probable longevity of technological civilizations.

What became clear from the meeting was that the field of SETI research

would have to encompass a very wide range of areas of intellectual investigation that included not only the natural sciences but also the social sciences

and engineering. The search for extraterrestrial intelligence was a very large

project that would take time, money, and a diverse team of scholars who

could bring theoretical innovations and pragmatic solutions to the technical

and conceptual issues that surrounded the endeavor.

One of the questions that participants quickly realized presented challenges

in thinking about how to pursue SETI research was our limited knowledge

about the abundance, or lack thereof, of extraterrestrial civilizations in the

galaxy or the rate at which life evolves into intelligence that can form technological civilizations. To address this, Drake took the seven agenda items that

had guided the conference and strung them together in an equation intended

to estimate the number of communicative civilizations extant in our galaxy.

The Drake Equation, as it has come to be known in the SETI community,

has guided SETI researchers for several decades now as scientists have worked

through the problems associated with finding extraterrestrial intelligence.

And it also adorns nerdy t-shirts available from a variety of sources online—

you can get yours from Amazon.

The variables Drake incorporated into the equation include what Drake

thought were the key elements of knowledge we would need to determine the

likelihood of finding extraterrestrial intelligence. The seven variables Drake

linked together are:

1. The average rate of star formation per year in our galaxy.

2. The fraction of those stars with planets.

3. The average number of planets that can potentially support life per star

that has planets.

4. The fraction of potentially life-supporting planets that actually go on to

develop life at some point.

5. The fraction of planets that support life which also actually go on to

develop intelligent life.

6. The fraction of civilizations that develop a technology that releases detectable

signs of their existence into space.


Science, Culture and the Search for Life on Other Worlds

7. The length of time during which such civilizations release detectable signals into space.

It’s important to understand that Drake did not intend the equation to

answer the question of how many intelligent civilizations there are in our galaxy.

Rather, the main thing the equation accomplishes is to clearly set out what we

need to know in order to estimate the number of intelligent civilizations there

might be available for us to contact. Being able to arrive at such an estimate is

important because it helps to determine whether or not SETI is worth bothering with. Depending on what numbers one puts into Drake’s equation, the

results can range from millions to one—Earth. If the answer is 1, then there isn’t

much point to pursuing SETI. For that matter, if the answer is 10 or 15, there

probably isn’t much point either, since given the vastness of our galaxy, such a

small number of civilizations are likely to be very far spread apart.

The Drake Equation has undergone some modifications in defining the

variables over the years, but it continues to provide a framework for thinking about what things we need to know in order to estimate the number of

worlds in our galaxy that might harbor intelligent life. Some of the variables

in the equation are fairly well understood. For example, over the past decade

a variety of new tools, such as the Galaxy Evolution Explorer (GALEX), the

Spitzer Space Telescope, and the Hubble Space Telescope have allowed for

new and more sophisticated observations related to the nature and rate of

star formation in our galaxy. This has led to a recognition that stars don’t

form at a consistent rate: low mass and large mass stars form at differential

rates related to the stellar environment (type of gas cloud) in which they

form. And an important discovery of the GALEX mission was the detection of low-level star formation in environments that had previously been

thought to lack star formation. One of the things accompanying these new

scientific resources is the fact that new observations and new data show that

our understanding of the universe continues to become more complex and

uncertain than initially imagined. Indeed, there have been somewhat competing models of star formation in the Milky Way and different opinions

about whether the rate is continuous or occurs in bursts separated by long

periods of relative inactivity.

While we appear to have a good understanding of the rate of star formation

in our galaxy now, it’s also clear that the rate has not been consistent throughout the history of the galaxy; the number must have been higher in the past

since our galaxy has converted most of its gas into stars. One question we

don’t know the answer to is how the rate of star formation might influence the

rate of the formation of planets that could harbor life, but this information is

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