Scientist Explains Why Aliens Haven’t Made Contact with Us Yet

In 1950, Nobel Prize-winning physicist Enrico Fermi famously wondered why humans have yet to encounter intelligent extraterrestrial life, given the vast number of potentially habitable planets in the Milky Way. There are many potential explanations for this conundrum, known as the Fermi Paradox. It may be that aliens have never existed in our galaxy or that they simply have not reached us yet. Other scientists have suggested that advanced alien civilizations have annihilated themselves before establishing contact with others.

Last week, planetary scientist Alan Stern, presented his explanation at the 49th annual meeting of the American Astronomical Society’s Division for Planetary Sciences in Provo, Utah. He suggested that most extraterrestrial life may live in subsurface oceans that are buried under a thick layer of ice or rock (or both), literally making it difficult for them to reach space.

Basically, aliens may be buried under too much ice to reach the stars and make contact with humans, says the planetary scientist. It’s a novel explanation for a decades-old question.

Stern is a planetary scientist at the Southwest Research Institute in Boulder, Colorado who served as the principal investigator for NASA’s New Horizons mission to Pluto. His proposed answer to the Fermi Paradox draws on findings that subsurface oceans are prevalent in our own solar system. Liquid oceans have been found buried under the icy crusts of several moons, including those of Jupiter and Saturn, and are believed to exist on several other planetary bodies in our solar system. Earth is the outlier– it’s the only planet in the solar system with a liquid ocean at the surface. It may be that this holds true throughout the rest of the Milky Way as well.

Buried oceans would provide stable environments for the evolution of intelligent life, Stern observes. Nutrients could be pumped into such ecosystems from hydrothermal vents in the ocean floor, whereas the thick shell of ice and rock would shield them from exposure to dangers from above the surface.

“Impacts and solar flares, and nearby supernovae, and what orbit you’re in, and whether you have a magnetosphere, and whether there’s a poisonous atmosphere — none of those things matter,” Stern told Space.

On the flip side, the dense ice cover would also isolate such a civilization from the cosmos, making it difficult to reach the surface and send broadcasts into space, much less accomplish spaceflight. Stern notes that it would be harder for an aquatic species to develop crewed space missions, given the need to carry around plenty of water for life support.