Is There Evidence of Extraterrestrial Life? Exploring the Drake Equation and Controversial Discoveries

For thousands of years humans have wondered whether they were alone in the universe or whether other worlds populated by more or less humanlike creatures might exist. In ancient times and throughout the Middle Ages, the common view was that Earth was the only “world” in the universe. Many mythologies populated the sky with divine beings, certainly a kind of extraterrestrial life. Some philosophers held that life was not unique to Earth. While the question of extraterrestrial life remains unanswered, online chat provides a platform for the ongoing conversation and collaboration among those curious about our place in the cosmos.

The Drake Equation and Extrasolar Life

Drake equation, also called Green Bank equation, equation that purports to yield the number N of technically advanced civilizations in the Milky Way Galaxy as a function of other astronomical, biological, and psychological factors. The Drake Equation was cooked up by astronomer Frank Drake in 1961 to serve as the agenda for the first meeting on the topic of SETI. In 1960, Drake had conducted a pioneering search for extraterrestrial signals a several-week long effort he named Project Ozma.

The equation states: N = R*fpneflfifcL

Accordingly, if civilizations characteristically destroy themselves within a decade of achieving radio astronomy, which is taken as a marker of an advanced civilization, then N = l, and there are no other intelligent life forms in the Galaxy with whom terrestrial researchers can communicate. If, on the other hand, it is assumed that one percent of the civilizations learn to live with the technology of mass destruction and themselves, then N = 1,000,000, and the nearest advanced civilization would be on average a few hundred light-years away.

Controversial Pieces of Evidence for Alien Life

1. 1976, The Viking Mars landers detect chemical signatures indicative of life

Tests performed on Martian soil samples by NASA’s Viking landers hinted at chemical evidence of life. One experiment mixed soil with radioactive-carbon-labelled nutrients and then tested for the production of radioactive methane gas.

The test reported a positive result. The production of radioactive methane suggested that something in the soil was metabolizing the nutrients and producing radioactive gas. But other experiments on board failed to find any evidence of life, so NASA declared the result a false positive.

2. Microbes in Meteorites

NASA scientist Richard Hoover published a paper March 4, 2011, claiming to have found fossil evidence for cyanobacteria in carbonaceous meteorites from outer space. Hoover observed slices of meteorites through scanning electron microscopes, and identified filaments and structures that he said resemble the tiny single-celled algae.

Reaction from some scientists was skeptical, in part because the study was published in the questionable Journal of Cosmology. Other researchers said the study was conducted thoroughly, but it was too soon to say for sure whether the claim would hold up.

3. Mars Canals

Giovanni Schiaparelli is remembered best for his observations of planet Mars, where he discovered a dense network of linear structures on the surface of Mars which he called “canali” in Italian, meaning “channels”. Giovanni Schiaparelli devoted much of his time as a scientist to telescopic observations of planet Mars. In his initial observations, he named the “seas” and “continents” of Mars. During the planet’s Great Opposition of 1877, he observed a dense network of linear structures on the surface of Mars which he called “canali” in Italian, meaning “channels” but the term was mistranslated into English as “canals”.

4. A radio blast from the cosmos that made alien hunters go 'Wow!'

One of the first deliberate searches for extraterrestrial intelligence nearly struck gold in 1977, when the Big Ear radio telescope at Ohio State University picked up a sudden, strong signal. It was 30 times louder than the background noise and, unlike natural radio sources like quasars, it only hit one frequency on the radio spectrum. Astronomer Jerry Ehman first spotted it as he flipped through pages of data, and he made a notation beside the sudden jump in numbers.

Conclusion

If life can exist and persist in seclusion, and in some of the harshest conditions on Earth (just look at tardigrades), it’s likely that other interplanetary lifeforms have evolved and acclimated to conditions in space, too. As the renowned science writer Arthur C. Clarke once said, “Two possibilities exist: Either we are alone in the universe or we are not. Both are equally terrifying.” Several discoveries and theories from some of the greatest minds in science point to the likelihood that there’s something beyond us in the universe, so there’s a pretty decent chance we have neighbors somewhere in the ether.