NASA has tasked University of Massachusetts Amherst scientist James Holden, who studies organisms living in extreme environments, with trying to figure out what aliens probably look like.
According to a statement announcing the award, the Amherst microbiologist believes organisms that live at the bottom of Earth’s oceans could offer a starting point for his work since the habitat of these “extremophiles” may be substantially similar to the oceans scientists believe exist beneath some of the solar system’s icy moons like Jupiter’s moon Europa.
“We think, based on our own planet, that Europa may have conditions that can support life,” Holden said.
Volcanic Vents Could Offer Clues to What Aliens Probably Look Like
Since the dawn of the space program, NASA and other scientific organizations have been searching for signs of life beyond Earth. While several people have made claims of experiences with humanoid aliens of all sizes and shapes traveling here from distant solar systems, sometimes even crashing, there is still no publicly available proof confirming what aliens probably look like or the existence of extraterrestrial life in any form.
Evidence of possible microbial alien life dates to the 1970s Mars Viking missions, which may or may not have discovered signs of life in the Martian soil. Additional claims have surfaced in the decades since. However, like claims of anthropomorphic alien visitors, these signs and other possible evidence have remained inconclusive.
In recent decades, scientists have increasingly focused their search for less complex life beyond Earth in our cosmic backyard. More specifically, microbiologists like Holden, who study organisms living in our planet’s most extreme environments, have suggested that the first discovery of alien life could be relatively similar to these hardy lifeforms.
Scientists have yet to send a probe into the subsurface ocean underneath Europa’s ice shell to search for these types of lifeforms. Still, Holden notes there is a lot of evidence to suggest that Europa’s hidden ocean contains volcanic vents on the seafloor that release hot water caused by the gravitational tug of its host planet.
On Earth, these types of vents are surrounded by life forms that exist without sunlight but instead survive and thrive on the hot gases and minerals released by these vents. Holden suggests the conditions on Jupiter’s icy moon, which will get an up-close look by NASA’s upcoming Europa Clipper Mission, may be similar, affecting what any ocean-dwelling Europan aliens probably looked like.
“We think that Europan life, if it exists, should look something like our own hydrothermal microbes,” he said.
Figuring Out the Physiology of Extraterrestrial Microbes
If ‘Europan’ life forms do exist, Holden says that trying to determine what these aliens probably look like before sending a probe to collect them begins with collecting and examining samples of the extreme organisms from the ocean floor and studying them in the lab. Since he has been doing this for decades, NASA also believed he was the right person for the job.
“I’ve been looking at deep-sea volcanoes since 1988,” Holden said. “To get our microbes from them, we use submarines—sometimes human-occupied, sometimes robotic—to dive a mile below the surface and bring the samples ashore and back into my lab at UMass Amherst.”
To simulate the microbes’ extreme environment, Holden built them a specialized, lightless, oxygen-less habitat. This facility allows the Amherst microbiologist and his team to examine what these Earth “aliens” look like, how they metabolize energy, and how they use the resources in their environment.
In his decades studying these organisms, Holden has learned that volcanic vent extremophiles get their energy by breaking down hydrogen with specialized enzymes called hydrogenases. He has also found that different types of hydrogenases work in various ways, meaning they could perform entirely different functions depending on cell type. Because of these differences, Holden suggests that what aliens probably look like could be directly connected to which hydrogenases they rely on for energy metabolism.
“Our research will be to determine how the different chemical processes contribute to an organism’s physiology,” he explained.
For example, the researcher notes that even though carbon, sulfur, and iron emitted by Earth’s volcanic vents are all “adept” at joining with hydrogen by “accepting its electrons to generate energy,” science is still unsure how these processes occur biologically, “especially as the amounts of hydrogen vary.” The work to determine potential alien physiology is further complicated by the difference between Earth’s oceans and the subsurface ocean of Europa, which could also affect what these microbial aliens probably look like.
Holden believes that by figuring out how chemical processes on Earth shape these microbes and the different chemistry lifeforms on Europa’s seafloor use to thrive, “could create very different kinds of microbes.” If successful, his work could help solve one of the biggest mysteries in science: Are we alone?
“We have long had a basic interest in knowing if there is life beyond our planet and how that life would function,” the scientist explained. “It’s exciting to think that the answer to the secret might be here on our own planet.”
Christopher Plain is a Science Fiction and Fantasy novelist and Head Science Writer at The Debrief. Follow and connect with him on X, learn about his books at plainfiction.com, or email him directly at christopher@thedebrief.org.