For as long as there have been humans, we have wondered about the nature of life itself, from where it originated all the way to how it will change in the future. As we continue to study evolution and the origins of life here on Earth, astronomers have begun to turn their attention to the stars to better understand whether or not life could exist on another planet. So far we have not found a planet with the same conditions as most of Earth. Instead we have found worlds that potentially have the ingredients for life but in much more hostile conditions.

Scientists like microbiologist Karen Lloyd study extreme locations on Earth to discover what kinds of environments life can survive in. On Thursday, June 25, 2026 Liberty Science Center was thrilled to welcome Lloyd, Wrigley Professor of Earth Sciences, and Marine and Environmental Biology at the University of Southern California and author of Intraterrestrials: Discovering the Strangest Life on Earth, to explore this topic in our latest Space Talk! Using the largest planetarium in the country, we were able to travel to some of the universe’s most extreme environments to search for microbes.

We began our search at the Laguna Caliente, a crater lake on Poás Volcano in Costa Rica. This lake is one of the most acidic natural bodies of water on Earth, with a pH hovering around 0, making it about as acidic as battery acid. If that isn’t extreme enough for you, the temperature in this lake can reach nearly 200°F. Even in a place as extreme as this, scientists have still discovered life. Specifically, microbes that have evolved to survive in highly acidic environments and generate energy for themselves from sulfur, iron, and arsenic to stay alive. That’s not the only volcano Lloyd has studied, though. We also stopped by Irruputuncu, a volcano in Chile, where scientists have found extremely unique microbes that survive in the high temperature, acidic, and low pressure environment over 15,000 feet above sea level.

Locations like these are similar to conditions that would have existed on Mars approximately 3.5 billion years ago, during a time when Mars very likely had the ingredients for life as we know it, like oxygen and water. Learning more about how life can survive in these conditions on Earth can help us better understand how life might have been possible on Mars in the ancient past.

Leaving these spectacular volcanoes behind, we next visited Guaymas Basin, located in the Gulf of California, which is tectonically active. The seafloor here is being slowly pulled apart. This lets scientists study life in multiple different ways. First, they find life that exists deep in the ocean floor, far from the light of the sun. Here, organisms are able to survive thanks to hydrothermal vents which release chemicals that specifically adapted microbes can thrive on, creating the basis for an ecosystem. Scientists can also drill into the much thinner surface of the seafloor here, revealing the vast amount of microbial life that exists beneath Earth’s surface.

Surveying these ocean environments helps scientists in their search for life in the modern-day solar system much farther away from Earth. One of Jupiter’s moons, Europa, is covered completely in ice on the surface but beneath its frigid exterior is a vast ocean, kept warm from heat leaking up from Europa’s hot interior. Conditions in this ocean could mirror those found at the deep ocean floor, or beneath Earth’s crust.

To learn even more about Karen Lloyd’s search for Earth’s most extreme life, and what it can teach us about life outside our planet, check out her book Intraterrestrials: Discovering the Strangest Life on Earth. Join us on July 9th, 2026 where we will be joined by Mike Davis, Project Manager at NASA, for our next Space Talk Unfolding the Universe with NASA’s James Webb Space Telescope.