Who is Nikku Madhusudhan? All about Cambridge University astronomer and author of study claiming signs of life beyond earth

A new study co-authored by Dr. Nikku Madhusudhan, an astronomer and professor at Cambridge University, signifies the possibility of extraterrestrial life on a planet 120 light-years away from Earth.

On April 15, the Astrophysical Journal Letters published the new study. It detailed the detection of possible signs of life on the planet K2-18b due to its abundance of dimethyl sulfide (DMS), a molecule produced by the living marine algae on Earth. The planet was first discovered in 2015 using the data from the Kepler Space Telescope.

As per the New York Times, Madhusudhan dubbed the discovery a "revolutionary moment" during a press conference on Tuesday, following the study's publication, adding:

"It is in no one’s interest to claim prematurely that we have detected life. Still, the best explanation for our observations is that K2-18b is covered with a warm ocean, brimming with life. This is a revolutionary moment. It’s the first time humanity has seen potential biosignatures on a habitable planet.”

Nikku Madhusudhan is an astrophysicist of Indian-origin who earned his Ph.D in Physics at MIT. He is currently an astrophysics and exoplanetary science professor at the University of Cambridge.

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Nikku Madhusudhan earned his bachelor's degree at the Indian Institute of Technology

Nikku Madhusudhan was born in India in 1980. He earned his bachelor's degree at the Indian Institute of Technology (BHU) in Varanasi. According to his LinkedIn profile, he earned his Ph.D at the Massachusetts Institute of Technology (MIT) in 2009. While earning his Ph.D, he reportedly trained under Dr. Sara Seager, an expert in exoplanet research.

Following his graduation, he was appointed a postdoctoral researcher at MIT, then at Princeton University between 2009 and 2011. He did his postdoctoral fellowship at Yale University between 2012 and 2013, and joined Cambridge University as a university lecturer in astrophysics in 2013.

Nikku Madhusudhan became a full-time astrophysics and exoplanetary science professor at the University of Cambridge in 2021. His many accolades include the Young Scientist Medal in Astrophysics in 2016 and the MERAC Prize in Theoretical Astrophysics in 2019.

Nikku Madhusudhan is also widely known for introducing the term "Hycean" planet in 2021. The term referred to planets with large water bodies similar to oceans and made up of an atmosphere containing methane, hydrogen, and other carbon compounds. The word "Hycean" is a portmanteau of "hydrogen" and "ocean."

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Exploring the planet K2-18b

The planet K2-18b is referred to as a "sub-Neptune" due to its size being larger than the Earth but smaller than Neptune. First discovered in 2015, it orbits around a cool dwarf star located 120 light years away from Earth.

In 2021, Dr. Nikku Madhusudhan hypothesized that "sub-Neptunes" could contain large oceans and atmospheric gases like hydrogen, methane, and other carbon compounds, leading to the name "Hycean."

In 2021, Madhusudhan used the James Webb Space Telescope to take a closer look at K2-18b, during which he detected that it contained similar characteristics to a "Hycean."

A closer look in 2023 led them to discover the plant possessed dimethyl sulfide (a compound made of sulfur, hydrogen, and carbon). This compound is most often produced by the living marine algae on Earth.

In 2024, Madhusudhan and his team took another look at K2-18b, during which they found the planet to emit stronger signals of dimethyl sulfide (thousands of times more than found on Earth) and dimethyl disulfide.

“It is a shock to the system. We spent an enormous amount of time just trying to get rid of the signal,” Madhusudhan said about the presence of dimethyl sulfide.

While this led the team to believe that K2-18b showed possible signs of life, Madhusudhan said it was too soon to predict whether the new planet was habitable. More research needs to be done to estimate whether the dimethyl sulfide on K2-18b behaves similarly to the compound on Earth, which may reportedly take years.