Uploaded September 2025 | Updated September 2026, 2 weeks ago
3I/ATLAS is the third known interstellar object to pass through our solar system, and the James Webb Space Telescope has now revealed details on it's chemistry and composition. Using Webb’s powerful infrared instruments, scientists detected the molecules and ices in its coma and tail, offering the most detailed look yet at the chemistry of an interstellar comet.
In this interview, John Michael Godier speaks with NASA astrophysicist Martin Cordiner, lead author of the JWST study on 3I/ATLAS. They explore how Webb captured its spectrum, what was found in the outgassing material, and how this discovery compares with ‘Oumuamua and Borisov, the first two interstellar visitors. Could 3I/ATLAS be a relic from the galaxy’s “cosmic noon” billions of years ago, preserving the raw materials of planetary formation?
By studying 3I/ATLAS, researchers hope to uncover clues about the origins of planets, the chemistry of other star systems, and the building blocks that may shape life across the Milky Way.
Cordiner, Martin A., Nathaniel X. Roth, Michael S. P. Kelley, Dennis Bodewits, Steven B. Charnley, Maria N. Drozdovskaya, Davide Farnocchia, Marco Micheli, Stefanie N. Milam, Cyrielle Opitom, Megan E. Schwamb, & Cristina A. Thomas (2025). JWST detection of a carbon dioxide dominated gas coma surrounding interstellar object 3I/ATLAS
arxiv.org/abs/2508.18209
00:00 – Introduction
02:15 – What makes 3I/ATLAS unique among interstellar objects
07:40 – How JWST was able to capture its spectrum
14:20 – A carbon dioxide–dominated coma and what it means
20:55 – Dust, ices, and the surprising chemistry of 3I/ATLAS
27:10 – Comparing 3I/ATLAS with ‘Oumuamua and Borisov
34:50 – A relic of “cosmic noon” and planetary formation
42:30 – What interstellar comets teach us about habitability
50:05 – Future missions and how spacecraft could study 3I/ATLAS
56:30 – Final thoughts on interstellar visitors and what comes next
YouTube Membership: youtube.com/channel/UCz3qvETKooktNgCvvheuQDw/join
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More JMG
youtube.com/c/JohnMichaelGodier
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Patreon: patreon.com/EventHorizonShow
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Music:
stellardrone.bandcamp.com
migueljohnson.bandcamp.com
leerosevere.bandcamp.com
aeriumambient.bandcamp.com
FOOTAGE:
NASA
ESA/Hubble
ESO - M.Kornmesser
ESO - L.Calcada
ESO - Jose Francisco Salgado (josefrancisco.org)
NAOJ
University of Warwick
Goddard Visualization Studio
Langley Research Center
Pixabay
3I/ATLAS is the third known interstellar object to pass through our solar system, and the James Webb Space Telescope has now revealed details on it's chemistry and composition. Using Webb’s powerful infrared instruments, scientists detected the molecules and ices in its coma and tail, offering the most detailed look yet at the chemistry of an interstellar comet.
In this interview, John Michael Godier speaks with NASA astrophysicist Martin Cordiner, lead author of the JWST study on 3I/ATLAS. They explore how Webb captured its spectrum, what was found in the outgassing material, and how this discovery compares with ‘Oumuamua and Borisov, the first two interstellar visitors. Could 3I/ATLAS be a relic from the galaxy’s “cosmic noon” billions of years ago, preserving the raw materials of planetary formation?
By studying 3I/ATLAS, researchers hope to uncover clues about the origins of planets, the chemistry of other star systems, and the building blocks that may shape life across the Milky Way.
Cordiner, Martin A., Nathaniel X. Roth, Michael S. P. Kelley, Dennis Bodewits, Steven B. Charnley, Maria N. Drozdovskaya, Davide Farnocchia, Marco Micheli, Stefanie N. Milam, Cyrielle Opitom, Megan E. Schwamb, & Cristina A. Thomas (2025). JWST detection of a carbon dioxide dominated gas coma surrounding interstellar object 3I/ATLAS
arxiv.org/abs/2508.18209
00:00 – Introduction
02:15 – What makes 3I/ATLAS unique among interstellar objects
07:40 – How JWST was able to capture its spectrum
14:20 – A carbon dioxide–dominated coma and what it means
20:55 – Dust, ices, and the surprising chemistry of 3I/ATLAS
27:10 – Comparing 3I/ATLAS with ‘Oumuamua and Borisov
34:50 – A relic of “cosmic noon” and planetary formation
42:30 – What interstellar comets teach us about habitability
50:05 – Future missions and how spacecraft could study 3I/ATLAS
56:30 – Final thoughts on interstellar visitors and what comes next
YouTube Membership: youtube.com/channel/UCz3qvETKooktNgCvvheuQDw/join
Podcast: hcreators.spotify.com/pod/show/john-michael-godier/subscribe
Apple: apple.co/3CS7rjT
More JMG
youtube.com/c/JohnMichaelGodier
Want to support the channel?
Patreon: patreon.com/EventHorizonShow
Follow us at other places!
@JMGEventHorizon
Music:
stellardrone.bandcamp.com
migueljohnson.bandcamp.com
leerosevere.bandcamp.com
aeriumambient.bandcamp.com
FOOTAGE:
NASA
ESA/Hubble
ESO - M.Kornmesser
ESO - L.Calcada
ESO - Jose Francisco Salgado (josefrancisco.org)
NAOJ
University of Warwick
Goddard Visualization Studio
Langley Research Center
Pixabay
