The Fermi Paradox

Where are the Aliens?

The Fermi Paradox takes its name from Nobel Prize-winning physicist Enrico Fermi, creator of the first nuclear reactor and a vital part of the Manhattan Project to develop the atomic bomb. In 1950 he and several colleagues were discussing the chances of discovering intelligent life in our Milly Way galaxy. While various people were expressing personal opinions, Fermi was making simple calculations on a paper napkin. He quickly realized that with so many sun-like stars in our galaxy, there must be many earth-like planets. At the end of the discussion about extraterrestrials, he simply stated, “Where are they?”

Observations from the Kepler Space Telescope confirm Fermi’s calculations. Most stars have planetary systems. In just a few short years, Kepler detected over 5000 exoplanets, planetary bodies orbiting stars in our galaxy. Astronomers now suspect that there might be up to 300 million earth sized bodies with the potential of having liquid water. Most biologists feel that once you have the long-term existence of liquid water, the chemistry of our universe allows life to develop. If life is so abundant, why haven’t we discovered another intelligent civilization? That’s the Fermi paradox.

It could be possible that life does not necessarily develop in most liquid water environments. Life might be a lot rarer than we anticipate. However, if life does typically develop in a liquid water environment, something must inhibit life from developing great intelligence and advanced technology. Astronomers call these inhibitors “great filters.”

Next month you’ll learn about “great filters,” and why the discovery of life on Mars, Jupiter’s moon Europa, or Saturn’s moon Enceladus, might actually be bad news for humanity. You won’t want to miss the coming July edition.

Ron Smith has spent his career lecturing and teaching astronomy, meteorology, and earth science. In retirement, Ron continues to enjoy sharing his love of science with others.