If aliens landed their spaceship in front of your school, what do you suppose would happen? Would they eat people? Would they ask to use the bathroom (chances are it was a long ride)? Would they ask your opinion on the new Mario movie about to hit theaters (and shouldn’t Mario speak with an Italian accent)?

Astronomers and other scientists are curious about the lack of contact with aliens (non-humans from other planets and galaxies) despite the existence of stars and galaxies that are billions of years old and many planets that scientists have determined to be capable of supporting life; moons like Saturn’s Titan and Enceladus and Jupiter’s Europa. And there are an estimated 200 to 400 billion stars in our galaxy, the Milky Way.

In the summer of 1950, the Italian-American physicist Enrico Fermi got into a conversation about UFO sightings, the age of the universe, the countless number of stars, and our lack of contact with other life forms. Fermi reportedly then asked, “Where is everybody?” His question was so intriguing to other scientists that it is called the Fermi paradox.

Today we know that many stars in our own Goldilocks Zone (a place that’s “just right” for supporting life) have planets that are the ideal distance from their stars so as not to be too hot or too cold to live on. And yet, we still have not found evidence of alien life here on Earth or in the form of electromagnetic radio waves.

Fermi’s paradox has led to one interesting hypothesis, an educated guess based on incomplete facts. The Dark Forest hypothesis says that alien life does exist but they’re hiding to avoid detection by aggressive alien life forms. Think of it this way. Our forests contain many animals and yet, when you walk through a forest, it is somewhat rare to see signs of life. You might startle a bird, for example, or a chipmunk might run past your feet in the leaves.

Can you think of other reasons aliens have not contacted us, in spite of this evidence that they should exist?

Learn More

Fermi Paradox

https://en.wikipedia.org/wiki/Fermi_paradox

Dark Forest Hypothesis

https://en.wikipedia.org/wiki/Dark_forest_hypothesis

Oceans on Other Planets

https://oceanservice.noaa.gov/facts/et-oceans.html

Saturn Moons

https://solarsystem.nasa.gov/moons/saturn-moons/titan/in-depth/

Exoplanets

https://exoplanets.nasa.gov/

Life Here and Beyond

https://astrobiology.nasa.gov/about/

Earth-sized Alien Worlds are Out There

https://www.science.org/content/article/earth-sized-alien-worlds-are-out-there-now-astronomers-are-figuring-out-how-detect-life

Do Aliens Exist?

https://www.nasa.gov/feature/do-aliens-exist-we-asked-a-nasa-scientist-episode-5

Drake Equation

https://en.wikipedia.org/wiki/Drake_equation

NASA Brings Standards of Evidence to UFO Search

https://www.rochester.edu/newscenter/nasa-brings-standards-of-evidence-to-the-search-for-ufos-527122/

Fermi Paradox

https://www.space.com/25325-fermi-paradox.html

The Search for Alien Tech

https://aeon.co/essays/technosignatures-are-a-sea-change-in-the-search-for-alien-life

What do Aliens look like?

https://www.imdb.com/title/tt1931230/

List of potentially habitable planets

https://en.wikipedia.org/wiki/List_of_potentially_habitable_exoplanets

Habitable Zone

https://exoplanets.nasa.gov/search-for-life/habitable-zone/

Scientists Discover plant with potential to support life

https://www.smithsonianmag.com/smart-news/scientists-discover-a-planet-with-the-potential-to-support-life-180980733/

What should you do if you meet and alien?

https://www.mentalfloss.com/article/626395/what-to-do-if-you-meet-an-alien