2. HISTORY OF SEARCH OF EXTRATERRESTRIAL LIFE
Is E.T. out there? Well, I work at the SETI Institute. That’s almost my name. SETI: Search for Extraterrestrial Intelligence. In other words, I look for aliens, and when I tell people that at a cocktail party, they usually look at me with a mildly incredulous look on their face. I try to keep my own face somewhat dispassionate.
— Seth Shostak, Senior Astronomer and Director, SETI Institute in Mountain View, California
Throughout history, humans have gazed up at the sky in awe and wonder. Our ancestors recorded the complex movements of stars, identified constellations and marked time by creating celestial based calendars. The stars also became the sources of countless myths and legends.In the fifth century B.C., the ancient Greek philosopher, Democritus, imagined “innumerable worlds of different sizes”, some of which brimming with life. The Roman poet, Titus Lucretius Carus, wrote about “other worlds” with “different tribes of men, kinds of wild beasts.”
The science fiction genre begun in the 17th century with the great German astronomer Johannes Kepler writing about a voyage to the Moon where travelers encountered reptiles-like creatures. Later in that century, the Dutch mathematician Christiaan Huygens concluded in his book that some of the other planets must harbor life and speculated on the conditions there.
In 1894, while viewing the Red Planet with his telescope, the American astronomer Percival Lowell spotted a web of “canals” on the surface of Mars. The structures appeared so elaborate to him, they could have been built only by intelligent entities.
During the last century, NASA and other space agencies around the world started sending satellites into space to explore our Solar System and to take photographs of the planets and their moons. Robotic devices were sent in unmanned space-crafts to explore their surfaces. In 1969, the first astronauts walked on the Moon and brought back lunar rocks and dust. Evidence of water was found on the Moon and Mars, as well as on Jupiter’s moon Europa. NASA’s Hubble Space Telescope has recently detected faint signatures of water in the atmospheres of five planets beyond our solar system. Amino acids, the building blocks of life, were discovered in meteorites that had fallen onto the Earth. In November 2014, European Space Agency’s Rosetta mission successfully placed a small spacecraft on the surface of a speeding comet 67P/Churyumov-Gerasimenko. And recently, NASA discovered significant spikes of methane on our neighboring Mars. Moreover, new and more powerful telescopes and better analytical tools have led to the discovery of hundreds of new planets orbiting other stars.
The search for extraterrestrial intelligence is still in its infancy and no one has found life anywhere other than on the Earth. However, the sheer immensity of our own Galaxy and the even larger immensity of our Universe (estimates place the number of stars in the Milky Way at 100 billion and the number of galaxies in the Universe also at 100 billion), has led many to realize that Earth-like planets may be quite commonplace within our Universe, and moreover, there may be a high chance of life on many of them—some of them may even harbor intelligent life.
Why should we care?
It can be argued that developing an understanding of our place in the Universe is key to the survival of our species. That knowledge can tell us something about our future technological prospects, the existential risks confronting us, and even throw light on the nature of evolution of the human species.
Unfortunately, Search for Extraterrestrial Intelligence (SETI) is not a government-funded effort. In fact, the prevailing belief in the US Congress is that SETI is a waste of tax-payer money since there are other far more pressing issues facing the nation today. Interestingly, SETI was once a project spearheaded by NASA, but the 103rd Congress eliminated the program 30 years ago. The same session saw the demise of the Superconducting Super Collider and with that vanished America’s hope of retaining her dominance in high-energy physics.
I will argue that SETI as a scientific discipline is no less important than other scientific areas where there are no immediate payoffs or benefits. We have built powerful particle accelerators to understand the nature of matter; we have mapped life’s genetic code with the long-term and hopeful notion of creating cutting-edge therapies to prolong and enrich lives, yet none of these endeavors promise to produce immediate practical applications. SETI, after all, is a quest for knowledge and new tools developed in SETI research has the potential to advance our scientific know-how by stimulating the development of a host of technologies such as superior satellite technology, materials science applications, and so on. These advances are expected to invigorate public interest in scientific education, develop new skills, create new employment opportunities and even stimulate the world economy. To quote Arthur C. Clarke “SETI is probably the most important quest of our time, and it amazes me that governments and corporations are not supporting it sufficiently”.
SETI research stems from the urge to explore the unknown and push the envelope of humankind’s persistent quest for knowledge. Finding answer to the age-old question of whether we are alone in our Galaxy may well be within our technological reach and, as some scientists believe, may even happen during our lifetime.