Indian-origin scientist claims detection of possible signs of life outside Earth

A team of researchers led by Indian-origin astrophysicist Dr Nikku Madhusudhan claimed on Thursday to have found the strongest indication yet of extraterrestrial life, not in our solar system but on a massive planet, known as K2-18b, that orbits a star 120 light-years from Earth, New York Times reported.

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A repeated analysis of the exoplanet's atmosphere suggests an abundance of a molecule that on Earth has only one known source, living organisms such as marine algae.

"It is in no one's interest to claim prematurely that we have detected life,” said Nikku Madhusudhan, an astronomer at the University of Cambridge and an author of the new study, at a news conference on Tuesday. Still, he said, the best explanation for his group's observations is that K2-18b is covered with a warm ocean, brimming with life.

"This is a revolutionary moment,” Madhusudhan said. "It's the first time humanity has seen potential biosignatures on a habitable planet." The study was published on Wednesday in the Astrophysical Journal Letters.

Other researchers called it an exciting, thought-provoking first step to making sense of what's on K2-18b. But they were reluctant to draw grand conclusions.

"It's not nothing,” said Stephen Schmidt, a planetary scientist at Johns Hopkins University. "It's a hint. But we cannot conclude it's habitable yet." As per the NYT, if there is extraterrestrial life on K2-18b, or anywhere else, its discovery will arrive at a frustratingly slow pace. "Unless we see ET waving at us, it's not going to be a smoking gun," said Christopher Glein, a planetary scientist at the Southwest Research Institute in San Antonio.

Canadian astronomers discovered K2-18b in 2017 while looking through ground-based telescopes in Chile. It was a type of planet commonly found outside our solar system, but one without any analogue near Earth that scientists could study closely for clues.