Uploaded April 2026 | Updated September 2026, 2 weeks ago
We now know that almost every star in the galaxy hosts a planetary system —
over 6,000 exoplanets have been confirmed so far, and counting. But knowing
they exist is just the beginning. What are these worlds actually made of?
Could any of them support life?
This lecture was filmed on 27 February 2026.
In this Royal Institution Discourse, Professor Jonathan Tennyson, Massey
Professor of Physics at UCL and Fellow of the Royal Society, explores how
cutting-edge advances in spectroscopy are transforming our understanding of
exoplanet composition.
Jonathan examines two of the biggest challenges facing researchers today:
the extreme temperatures on some exoplanets that produce extraordinarily
complex spectral signatures, and the fact that for most exoplanets, we
can't even see them directly. He reveals the techniques scientists use to
overcome these obstacles, combining spectral observation with quantum
mechanical methods to decode the chemical fingerprints of distant worlds.
This lecture was recorded at the Royal Institution in London as part of
the prestigious Friday Evening Discourse series, one of the oldest science
lecture series in the world, dating back to 1825. It was delivered in
celebration of UCL200.
---
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Jonathan Tennyson is Massey Professor of Physics at University College London. He received a B.A. in Natural Sciences from King’s College, Cambridge and a DPhil in Theoretical Chemistry from the University of Sussex.
After doing post-doctoral research at the University of Nijmegen in the Netherlands and the UK’s Daresbury Laboratory, he joined UCL as a “New Blood” lecturer in 1985 where he has been ever since. He served as Head of Department 2004-11, stepping down to run the ExoMol project.
He was elected a Fellow of the Royal Society in 2009 and has received several prizes including the 2022 European Research Council INSPIRE public outreach Prize and the 2025 Gold Medal of the Royal Astronomical Society.
He is Chair of Blue Skies Space Ltd who recently launched their first space satellite, Mauve.
---
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---
Chapters:
0:00 The Nobel Prize Photo That Discovered the First Exoplanet
1:16 Why We've Only Found 6,000 Planets in a Galaxy of 20 Trillion Stars
2:14 Have We Actually Found Earth 2.0? The Honest Answer
3:27 Planets Hotter Than Most Stars — Lava Worlds & 4,000° Atmospheres
4:16 The Two Techniques That Find Exoplanets
5:33 What Are Exoplanets Actually Made Of?
7:44 Why Auguste Comte Was Spectacularly Wrong About the Stars
8:12 How We Read the Chemistry of Distant Suns
12:48 The Moment I Fell in Love with Quantum Mechanics
16:36 Detecting Water on Jupiter — and Then on Another World
19:17 The First Detection of Water on an Exoplanet
21:28 Three Ways to Analyse an Alien Atmosphere
27:40 The Clever Trick That Detects Molecules You Can't See
31:06 Can We Just... Look at the Planets Directly?
33:44 What Temperature Actually Means to a Physicist
35:18 Building the World's Most Complete Database of Hot Molecule Chemistry
47:07 Getting Schoolchildren to Do Real Astronomical Research
50:28 The New Frontier: Ultraviolet Light & Molecules Tearing Apart
53:16 What Comes Next for Exoplanet Science
---
#exoplanets, #spectroscopy, #astrophysics, #spacescience, #JonathanTennyson, #Royal Institution, #astronomy, #atmosphere #planetcomposition, #jameswebbspacetelescope #alienplanets, #quantummechanics, #sciencelecture2026
We now know that almost every star in the galaxy hosts a planetary system —
over 6,000 exoplanets have been confirmed so far, and counting. But knowing
they exist is just the beginning. What are these worlds actually made of?
Could any of them support life?
This lecture was filmed on 27 February 2026.
In this Royal Institution Discourse, Professor Jonathan Tennyson, Massey
Professor of Physics at UCL and Fellow of the Royal Society, explores how
cutting-edge advances in spectroscopy are transforming our understanding of
exoplanet composition.
Jonathan examines two of the biggest challenges facing researchers today:
the extreme temperatures on some exoplanets that produce extraordinarily
complex spectral signatures, and the fact that for most exoplanets, we
can't even see them directly. He reveals the techniques scientists use to
overcome these obstacles, combining spectral observation with quantum
mechanical methods to decode the chemical fingerprints of distant worlds.
This lecture was recorded at the Royal Institution in London as part of
the prestigious Friday Evening Discourse series, one of the oldest science
lecture series in the world, dating back to 1825. It was delivered in
celebration of UCL200.
---
Join this channel to get access to Member perks:
youtube.com/channel/UCYeF244yNGuFefuFKqxIAXw/join
Subscribe for more world-class science videos: bit.ly/RiSubscRibe
---
Jonathan Tennyson is Massey Professor of Physics at University College London. He received a B.A. in Natural Sciences from King’s College, Cambridge and a DPhil in Theoretical Chemistry from the University of Sussex.
After doing post-doctoral research at the University of Nijmegen in the Netherlands and the UK’s Daresbury Laboratory, he joined UCL as a “New Blood” lecturer in 1985 where he has been ever since. He served as Head of Department 2004-11, stepping down to run the ExoMol project.
He was elected a Fellow of the Royal Society in 2009 and has received several prizes including the 2022 European Research Council INSPIRE public outreach Prize and the 2025 Gold Medal of the Royal Astronomical Society.
He is Chair of Blue Skies Space Ltd who recently launched their first space satellite, Mauve.
---
The Ri is on Twitter: twitter.com/ri_science
and Facebook: facebook.com/royalinstitution
and TikTok: tiktok.com/@ri_science
Listen to the Ri podcast: podcasters.spotify.com/pod/show/ri-science-podcast
Donate to the RI and help us bring you more lectures: rigb.org/support-us/donate-ri
Our editorial policy: rigb.org/editing-ri-talks-and-moderating-comments
Subscribe for the latest science videos: bit.ly/RiNewsletter
Product links on this page may be affiliate links which means it won't cost you any extra but we may earn a small commission if you decide to purchase through the link.
---
Chapters:
0:00 The Nobel Prize Photo That Discovered the First Exoplanet
1:16 Why We've Only Found 6,000 Planets in a Galaxy of 20 Trillion Stars
2:14 Have We Actually Found Earth 2.0? The Honest Answer
3:27 Planets Hotter Than Most Stars — Lava Worlds & 4,000° Atmospheres
4:16 The Two Techniques That Find Exoplanets
5:33 What Are Exoplanets Actually Made Of?
7:44 Why Auguste Comte Was Spectacularly Wrong About the Stars
8:12 How We Read the Chemistry of Distant Suns
12:48 The Moment I Fell in Love with Quantum Mechanics
16:36 Detecting Water on Jupiter — and Then on Another World
19:17 The First Detection of Water on an Exoplanet
21:28 Three Ways to Analyse an Alien Atmosphere
27:40 The Clever Trick That Detects Molecules You Can't See
31:06 Can We Just... Look at the Planets Directly?
33:44 What Temperature Actually Means to a Physicist
35:18 Building the World's Most Complete Database of Hot Molecule Chemistry
47:07 Getting Schoolchildren to Do Real Astronomical Research
50:28 The New Frontier: Ultraviolet Light & Molecules Tearing Apart
53:16 What Comes Next for Exoplanet Science
---
#exoplanets, #spectroscopy, #astrophysics, #spacescience, #JonathanTennyson, #Royal Institution, #astronomy, #atmosphere #planetcomposition, #jameswebbspacetelescope #alienplanets, #quantummechanics, #sciencelecture2026
