In October 1995, Michel Mayor and Didier Queloz made a groundbreaking discovery: the first exoplanet orbiting a solar-type star. This moment marked the beginning of a new era in astronomy and planetary science, earning the Swiss pair the 2019 Nobel Prize in Physics. In a recent visit to the Sorbonne, Queloz shared some of his insights with Radio France Internationale.
Since the first discovery, nearly 6,000 exoplanets have been confirmed, with thousands more candidates awaiting verification. Each one offers a small glimpse into the diversity of planetary systems across the galaxy.
While both Mayor and Queloz are Swiss, they come from the French-speaking region of Switzerland and have long-standing academic ties to French institutions.
Growing interest in exoplanets
Their discovery reverberated strongly through the French scientific community, contributing to a surge of interest in exoplanetology in France. Professor Queloz, for example, has collaborated with Paris Sciences et Lettres University and recently delivered a public lecture at Sorbonne University.
During his visit to Paris, Queloz explained: “Looking for exoplanets is essentially looking for us.”
His words capture the deeper motivation behind this cosmic quest - not merely cataloging distant worlds, but seeking to understand our own place in the universe.
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He added: “We want to understand the solar system,” he explained. “We have only one solar system. We look at the other systems to understand how do we fit into the grand picture.”
In essence, by studying other planetary systems, scientists are holding up a mirror to our own. Are the conditions that led to Earth’s habitability common or exceedingly rare? Is our solar system an outlier, or just one example among countless others?
Each exoplanet discovered - whether it's a gas giant hugging its star or a rocky Earth-sized world in a habitable zone - adds a piece to the puzzle, he explained.
And with each piece, we refine our understanding not only of planetary formation and dynamics but also of the delicate chain of events that allowed life to emerge here.
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Philosphy and science
Queloz emphasised that this search is as much philosophical as it is scientific: “Understanding the many other planets helps us to understand ourselves,” he said, “and maybe ask the question, is the Earth a unique planet in the cosmos, or do we have plenty of other Earths?”
The question remains open. Despite thousands of discoveries, no other planet has yet been found that mirrors Earth in all the key characteristics that allow it to support life as we know it.
But the search continues, driven by curiosity, by wonder, and by the deeply human desire to understand where we come from and whether we are alone.
In the end, the search for exoplanets is not just about finding other worlds. It’s about finding context for our world, about seeing Earth not in isolation, but as part of a vast and varied cosmic tapestry.
