Indian-British Scientist’s Exoplanet Discoveries Stir Hope On Alien Life

The vast cosmos has always been a source of intrigue, with the quest for life beyond Earth spanning decades. The recent revelation of potential biosignatures on the exoplanet K2-18b has sent ripples through the astronomical community. This has prompted a retrospective look at the past decade of discoveries that have revolutionized our understanding of planetary habitability.

The journey began with NASA’s Kepler mission, which opened the floodgates to the discovery of thousands of exoplanets, planets beyond our solar system. Among these, a select few have been found within the coveted habitable zone, a region around a star where conditions could potentially support liquid water, a key ingredient for life as we know it.

One of the earliest and most celebrated discoveries was Kepler-186f, a rocky planet approximately 500 light-years away from Earth. Similar in size to our home planet and orbiting within its star’s habitable zone, the discovery of Kepler-186f in 2014 marked a significant milestone in the search for Earth-like planets.

New Discoveries

In 2017, the discovery of a system of seven Earth-sized planets orbiting a dim red dwarf named TRAPPIST-1 further piqued the interest of the scientific community. Three of these planets, named e, f, and g, were found within the habitable zone. Their size and proximity to each other made them ideal candidates for atmospheric analysis. However, subsequent studies raised concerns about the extreme stellar flares of their host star, which could potentially strip away their atmospheres, casting a shadow over their habitability.

Closer to home, the discovery of Proxima b in 2016, a mere 4.2 light-years away, sparked global interest. Slightly larger than Earth and orbiting within a potentially temperate zone, Proxima b seemed a promising candidate for life. However, its parent star, Proxima Centauri, is known for its volatility, raising doubts about the planet’s long-term habitability.

In recent years, LHS 1140 b, a dense, rocky planet 40 light-years away, has emerged as a strong contender in the search for extraterrestrial life. With a stable orbit and early indications of an atmosphere, it is a prime target for upcoming investigations by the James Webb Space Telescope (JWST).

The Spotlight on K2-18b

Adding to the growing list of potential life-supporting planets is TOI 700 d, confirmed in 2020 by NASA’s TESS observatory. Receiving nearly the same amount of light as Earth and orbiting a quiet red dwarf, it raises hopes for a relatively undisturbed environment. However, atmospheric data remains elusive, leaving its habitability status uncertain.

The current spotlight, however, is on K2-18b, a sub-Neptune-sized planet first identified in 2015. Located 124 light-years away, the planet has shown signs of water vapor, methane, and carbon dioxide. In 2023, astronomer Nikku Madhusudhan and his team reported faint traces of dimethyl sulfide (DMS), a molecule produced on Earth only by life. New observations in 2025 using a different JWST instrument strengthened the case for DMS and a related compound, dimethyl disulfide (DMDS).

Despite these promising findings, experts urge caution. Dr. Ryan MacDonald of the University of Michigan stated, “These new JWST observations do not offer convincing evidence that DMS or DMDS are present.” Others, like NASA’s Nicholas Wogan, have acknowledged the improved data but stress the need for independent verification.

The consensus among scientists is that while these planets show potential, confirming life—or even just conditions for it—remains an immense challenge. The “five-sigma” statistical confidence required to claim a discovery in physics is still a long way off for most of these detections.

As we continue to explore the cosmos, we are reminded of the words of Dr. Thomas Beatty of the University of Wisconsin-Madison, who encapsulated the current state of affairs, saying, “Right now, we’re seeing a lot of ‘maybes.’” He added, “But even a maybe is remarkable, considering how far we’ve come.”

The search for extraterrestrial life has transformed our place in the cosmos—from passive observers to active explorers of worlds that, not so long ago, existed only in science fiction. As technology advances and instruments like JWST continue to refine their vision, the quest continues, reminding us of the vastness of the universe and the potential it holds.