Hello, Is Anyone Out There? Students Ponder Extraterrestrial Intelligence
One of the big topics of discussion in my undergraduate Astrobiology class at Appalachian State University (ASU) is the question of intelligent life beyond Earth, as it is, in my view, probably the single most intriguing question in astrobiology. Indeed, the prospect of life existing beyond Earth has fascinated humankind for centuries, with the first scientific thinking on the subject dating back to the Ancient Greeks. Advanced modern technology has led to formalized study on the Search for Extraterrestrial Intelligence (abbreviated, SETI), and the popularization of this topic over the last several decades has been spurred on from the pioneers of SETI, most notably the astronomers Frank Drake and Jill Tarter of the SETI Institute in Mountain View, CA, and the late astronomer Carl Sagan.
While we have no evidence whatsoever for life of any kind, even the most simplest microbes, beyond our planet, humans seem to be drawn to this search, and in so doing, ponder the possibilities of what could be out there, and what such a discovery would mean for life on Earth. A recent boost in proponents of SETI came just earlier this month with a report from a new data analysis from NASA’s Kepler spacecraft which revealed that there could be as many as 40 billion Earth-like planets in our Galaxy, alone. This means that one out of every five Sun-like stars in the Galaxy could house a potentially habitable planet!
(You can interact with some of Kepler’s discoveries with this cool animation tool).
So, then where is everybody? This apparent contradiction in seemingly high estimates for extraterrestrial intelligent life in the Galaxy and our lack of evidence for such life was famously questioned by the physicist Enrico Fermi in 1950, and is known as the Fermi Paradox, which has several proposed theoretical solutions. In spite of this paradox, many scientists remain hopeful that extraterrestrial intelligence is out there, with a reasonable chance of detecting it, with modern estimates for potential communicative civilizations achieved through the Drake Equation (sometimes called the Sagan-Drake Equation).
Recently, I gave my Astrobiology class an assignment to write whether they thought SETI — the ongoing search for intelligence beyond Earth — was a waste of time and/or money, knowing that, with the vast distances of space, any possible radio signal from an intelligent civilization could take thousands of years (which is likely a minimum) to reach us, if they were being sent at all?
This assignment was a contest, such that the most convincing response would be published on this astronomy blog site. Below are two chosen excerpts, and a third in its entirety. All students are sophomores in ASU’s Honors College, many are non-science majors, and all illustrate several of the prevailing viewpoints that span generations of scientists today.
Student Jack Schaufler cites the large gain in SETI against the small economic cost:
SETI will continue to expand, with new detectors suitable for optimal wavelengths predicted to increase the list of SETI targets to hundreds of thousands of stars. The potential implications of contacting intelligent life are huge. It would drastically change our lives here one Earth, causing an increase in scientific interest as well as a shock throughout the religious world. The risk involved with maintaining SETI is a mere 2.5 million dollars a year, equal to the price of 5 Tomahawk Cruise Missiles out of the 830 billion dollars the US spends on defense a year. Keeping SETI operational requires much less risk than the potential reward.
As a counter view, student Zachary Lachance thinks there is probably a very low likelihood for success with SETI:
Due to the idea that older intelligent life should have already existed in the universe and the lack of evidence to support the idea that this intelligent life has made contact with Earth, it is safe to assume that SETI will fail because intelligent life should have already colonized the galaxy…. Unless intelligent life is so rare that some form of it has yet to colonize the Galaxy or communicate, SETI will still most likely fail due to the small probability of intelligent life existing or the large distance between Earth and another intelligent civilization. Once you add in all of the planets that do not, as far as we can tell, contain intelligent life, finding intelligent life would still be similar to finding a needle in a large, seemingly never-ending haystack. Therefore, the prospects of SETI seem bleak and SETI is destined to fail.
The most convincing overall response was by student Jonathan Solomon. It is pro-SETI.
The Search for Extraterrestrial Intelligence (SETI) uses radio waves as a means of hopefully finding another civilization – one that is capable of receiving, deciphering, and transmitting radio signals of their own. The entire search relies upon several assumptions about other intelligent civilizations based on the history of the evolution of the human race’s technological capabilities and curiosities. One powerful assumption is that, evidenced by the age of the universe, Earth is in its infant stages regarding technology. If there is other intelligent life out there then it is reasonable that they are much older and more technologically advanced than humans are. Humanity has only had radio waves for about one hundred years, and the technological advances achieved during that period have been astounding. Roughly forty years after the advent of radio waves came nuclear technology. That is such an infinitesimally small time on the cosmic scale between harnessing to radio waves and having the capability of annihilating intelligent life as we know it. There are other assumptions about extraterrestrial intelligence that fuel debates between SETI proponents and opponents.
Many argue that if advanced alien civilizations exist, then they should have already made contact with Earth; if not the aliens themselves, then feasibly the aliens would have some form of self-replicating robots that would be capable of colonizing the universe. If, indeed, However, it is also possible that extraterrestrial civilizations could simply be thousands of light-years away and have simply not gotten close enough to us for humans to realize their presence. Another possible explanation is that interstellar travel is much more difficult than we currently assume. For instance, considering the high speeds that interstellar vehicles would have to travel, ensuring the safety of the vehicle would be extremely difficult (Shostak, 2002).
The importance of SETI, in my opinion, is that it brings hope. Knowing that somewhere out in the cosmos some intelligent civilization could have figured out how to coexist in such a way that it did not self-destruct would prove that humanity is not doomed. Ben Zuckerman, astrophysicist at UCLA, writes about how it is ironic that humanity is looking for extraterrestrial intelligence due to the overpopulation and overconsumption of our own planet (Zuckerman, 2002). I agree with him that humans need to change our consumption patterns if we wish to survive on this planet; however, I do not believe that the allocation of such a small amount of funds, when compared to the military budget, for example, is a waste. Rather, the spending of such a small amount of money on such a high reward is like a cosmic scratch card. If we do not end up winning, we did not expend many resources, and at least we tried; but if we end up hitting the jackpot, the implications are enormous.
[References: Shostak, Seth. SETIs Prospects Are Bright. Mercury. 2002. Print; Zuckerman, Ben. Why SETI Will Fail. Mercury. 2002. Print].
One of the most thought-provoking views on extraterrestrial civilizations comes, in my opinion, from Carl Sagan. This short video is excerpted from his original Cosmos broadcasts, and to me best summarizes the profound implications of finding life beyond Earth, within the context of a strong scientific platform:
If you believe life is out there and want to help in the search for ET signals, learn more about how you can participate in the SETI@home citizen science project that uses personal computers to search for and analyze radio signals.