October 10, 2025

Didier Queloz: The discovery that rewrote our view of other worlds

Thirty years ago, Swiss physicist Didier Queloz helped detect the first planet outside our Solar System—an achievement that reshaped modern astrophysics. Today, the ETH Zurich professor leads the Centre for Origin and Prevalence of Life (COPL) and is pushing the search for life beyond Earth even further.

In the ETH video, Queloz looks back on the moment the team announced the discovery—and on how quickly it became clear that the find was bigger than anyone expected. “We completely changed the astrophysics,” he says.

The real surprise was the planet itself: 51 Pegasi b (“51 Peg b”), named after its host star 51 Pegasi. It was not the kind of world the researchers had anticipated—setting off new questions about how planetary systems form and what “typical” planets might look like across the galaxy.

From a breakthrough to the big question: LIFE

For Queloz, exoplanets quickly lead to the next frontier: what they might tell us about life. He is clear that the answer will not come overnight—but he wants to help build the field that will eventually deliver it.

That motivation is also why he is now at ETH Zurich, where he leads COPL and works with colleagues to connect astrophysics, planetary science and life sciences around one of the biggest questions in research.

Inspiring the next generation

Queloz also emphasizes the role scientists have beyond discovery: passing on knowledge, curiosity and ambition. “Science will only exist because we’re preparing the next generation,” he notes—making communication and inspiration part of the job.

And while the search is still ongoing, his optimism remains: “I really hope that we’re going to find life beyond Earth… It’s just a matter of time.”