Square away your personal philosophy now; proof of life beyond earth is coming. Stargazing image via shutterstock
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Are we ready to meet ET?
How will humankind react after astronomers hand over rock-solid scientific evidence for the existence of life beyond the Earth? No more speculating. No more wondering. The moment scientists announce this discovery, everything will change.
Searching for signs of life
Astronomers have now identified thousands of planets in orbit around other stars. At the current rate of discovery, millions more will be found this century.
Having already found the physical planets, astronomers are now searching for our biological neighbors. Over the next fifty years, they will begin the tantalizing, detailed study of millions of planets, looking for evidence of the presence of life on or below the surfaces or in the atmospheres of those planets.
And it’s very likely that astronomers will find it. Despite the fact that more than one-third of Americans surveyed believe that aliens have already visited Earth, the first evidence of life beyond our planet probably won’t be radio signals, little green men or flying saucers. Instead, a 21st century Galileo, using an enormous, 50-meter-diameter telescope, will collect light from the atmospheres of distant planets, looking for the signatures of biologically significant molecules.
Astronomers filter that light from far away through spectrometers – high-tech prisms that tease the light apart into its many distinct wavelengths. They’re looking for the telltale fingerprints of molecules that would not exist in abundance in these atmospheres in the absence of living things. The spectroscopic data will tell whether a planet’s environment has been altered in ways that point to biological processes at work.
If we aren’t alone, who are we?
With the discovery in a distant planet’s light spectrum of a chemical that could only be produced by living creatures, humankind will have the opportunity to read a new page in the book of knowledge. We will no longer be speculating about whether other beings exist in the universe. We will know that we not alone.
Astronomers as paradigm-shatterers
At certain moments throughout history, astronomers’ discoveries have exerted an outsized influence on human culture. Ancient Greek astronomers unflattened the Earth – though many then chose to forget this knowledge. Renaissance scholars Copernicus and Galileo put the Earth in motion around the Sun and moved humans away from the center of the universe. In the 20th century, Edwin Hubble eliminated the very idea that the universe has any center at all. He demonstrated that what the universe has is a beginning in time and that, bizarrely, the universe, the very fabric of three-dimensional space, is expanding.
Clearly, when astronomers offer the world bold new ideas, they don’t mess around. Another such paradigm-shattering new idea may be in the light arriving at our telescopes now.
Author : David A Weintraub – Professor of Astronomy, Vanderbilt University
This article originally appeared on The Conversation