When one encounters the word “extraterrestrial,” images of alien creatures from sci-fi films often come to mind. However, recent research suggests that alien life may exist off screen as well.
A Sept. 28 study released by NASA provides strong evidence for the presence of water on Mars. Extraterrestrial life has been a topic of conversation for astrobiologists and casual stargazers alike, and although many scientists have long believed that other planets can be conducive to life, this new evidence serves as an advancement in the investigation.
Sara Seager, a professor of planetary science and physics at the Massachusetts Institute of Technology, noted that if Mars is habitable, its residents likely exist in the form of little bacteria. Nonetheless, this has broader implications for the possibility of more complex life on other planets both in our solar system and in others.
“If life is on Mars, then anywhere there are the ingredients for life, life can evolve,” Seager said. “… The chance of there being complex life to me seems really high.”
Seager also said there are billions of planets in existence and that any number of them could potentially sustain life if the conditions are right. Along with others in her field, Seager currently works to determine whether there are gases on these planets that don’t occur naturally. If so, this is another indicator that there could be some form of life generating these gases.
“At the personal level, I really hope there’s life on Mars,” Seager said. “If we find life on Mars that’s independent, that is phenomenal and that will give us much more confidence in answering the question about more complex life on other planets.”
Thomas Kuchar, a research astronomer at Boston College, had a similarly optimistic attitude about extraterrestrial life. He noted that if life forms on Earth can adapt to certain extreme conditions, there is no reason that they can’t evolve on planets with similarly hostile environments.
“The physics and chemistry and biology that help life evolve on Earth are not unique to Earth,” Kuchar said. “We don’t have a monopoly on those processes.”
However, Kuchar was unsure about the actual existence of intelligent life.
“That’s going to be a big question,” he said. “We don’t know what’s necessary to evolve intelligent life in these environments.”
Despite this uncertainty, many scientists in the field are dedicated to continuing the investigation of extraterrestrial life. Mary Beth Wilhelm, a scientist in the Planetary Science branch of NASA, said that she and her colleagues are “chipping away at pieces of the puzzle.”
Although the scientists involved in the study said there is still no conclusive evidence for life on Mars because they cannot determine if the water is too briny, they are encouraged by the fact that there is currently water flow on the planet.
“I think our results will affect others’ research, many who are better suited to assess and test a link to possible astrobiology,” said Matthew Chojnacki, a staff scientist at the University of Arizona and one of Wilhelm’s former colleagues. “…Laboratory studies could examine how extremophiles fare in hydrated [salty] fluids thought to be analogous to what we detected on Mars … Terrestrial analog studies may look for similar fluid concentrations in nature and if they harbor any life.”
Extraterrestrial research is an exciting endeavor for those in the field and Andrew West, a professor of astronomy at Boston University, is one of the many who look forward to the future of astrobiology.
West previously taught a class at BU called “Alien Worlds” and studies how stars affect the habitability of other planets. When asked about the recent discovery of water on Mars, he expressed his enthusiasm about its implications.
“The way science works is we take incremental steps,” West said, “and this is another step that gets us a little closer to finding life elsewhere.”
