Into the Impossible With Brian Keating
Science:Natural Sciences
In 2009, Kaltenegger realized that a telescope like JWST would see only tiny signals from atmospheric gases during each transit, so in order to achieve any statistical certainty, astronomers would need to observe dozens or even hundreds of transits, which would take years. Acting on this insight, astronomers started to seek Earths in close orbits around dimmer, colder red dwarf stars, where atmospheric signals will be less drowned out by starlight and transits repeat more frequently.
In 2017, astronomers announced the discovery of seven rocky planets around a red dwarf star called TRAPPIST-1. Then in September, the SPECULOOS-2 system emerged as a backup. These stars are close. They’re dim and red. They each have multiple rocky planets that transit. And as of the summer, the JWST is up and running even better than expected. It will spend a sizable fraction of the next five years staring hard at these messy globes of rock and chemicals spinning around their strange stars. For theoreticians like Kaltenegger who went from daydreaming of alternate Earths to churning out predictions about their atmospheric chemistry, decades of anticipation have given way to a slow fade-in of squiggly spectra on computer monitors.
The goal at the time was to compare spectra from rocky, temperate planets to what Earth’s spectrum would look like from far away, seeking conspicuous signals like a surplus of oxygen due to widespread photosynthesis. Kaltenegger’s objection was that, for the first 2 billion years of Earth’s existence, its atmosphere had no oxygen. Then it took another billion years for oxygen to build up to high levels. And this biosignature hit its highest concentration not in Earth’s present-day spectrum, but during a short window in the late Cretaceous Period when proto-birds chased giant insects through the skies.
Without a good theoretical model for how Earth’s own spectrum has changed, Kaltenegger feared, the big planet-finding missions could easily miss a living world that didn’t match a narrow temporal template. She needed to envision Earth as an exoplanet evolving through time. To do this, she adapted one of the first global climate models, developed by the geoscientist James Kasting, which still includes references to the 1970s magnetic-tape era it originated in. Kaltenegger developed this code into a bespoke tool that can analyze not only Earth through time but also radically alien scenarios, and it remains her lab’s workhorse.
🎧 On Apple devices, click here, https://apple.co/39UaHlB scroll down to the ratings and leave a 5 star rating and review The INTO THE IMPOSSIBLE Podcast.
Other ways to rate here: https://briankeating.com/podcast
Support the podcast on Patreon https://www.patreon.com/drbriankeating
or become a Member on YouTube- https://www.youtube.com/channel/UCmXH_moPhfkqCk6S3b9RWuw/join
Learn more about your ad choices. Visit megaphone.fm/adchoices
How Evidence Sometimes Loses Out to Emotion The AlphaMind Podcast with Brian Keating (#321)
Life's Edge: Exploring the Boundary between Living & Nonliving | Carl Zimmer | Into the Impossible (#320)
Rebuilding Higher Education for the 21st Century | Brian Keating & James Altucher (#319)
Felix Flicker: The Magic of Physics on The Into The Impossible Podcast (#318)
Fighter Pilot's Stealth Secrets to DOMINATION: Hasard Lee: The Into the Impossible Podcast (#317)
RED FLAGS! Room Temperature Superconductor or FRAUD? Jorge Hirsch on the INTO THE IMPOSSIBLE Podcast (#316)
The Known Unknowns: Exploring the Humbling Universe | Lawrence Krauss | Part 2 (#315b)
The Known Unknowns: Exploring the Humbling Universe | Lawrence Krauss | Part 1 (#315a)
Brian Keating on the Jordan Harbinger Show (#314)
Brian Keating on the Modern Wisdom Podcast with Chris Williamson (#313)
Marc Kamionkowski: Crises In Cosmology (#312)
Sir Roger Penrose | The Emperor’s New Mind: Consciousness & Computer | INTO THE IMPOSSIBLE Podcast (#311)
“I only had 30 minutes to Invent Eternal Inflation!” Andrei Linde | INTO THE IMPOSSIBLE Podcast (#310)
Superconductor Smackdown: Breakthrough or ‘Probable Fraud’? (#309)
Eric Weinstein: The Crazy Structure of the Universe (#308)
Avi Loeb: `Oumuamua is EXTRATERRESTRIAL (#307)
Can Scientists Be Spiritual? Alan Lightman | Into The Impossible Podcast (#306)
Martin Bauer: The Revolutionary Stern-Gerlach Experiment (#305)
Studying Autism with BRAINS Grown In Space | Alysson Moutri on The INTO THE IMPOSSIBLE Podcast (#304)
When Will We Detect Dark Matter? Elena Aprile and the XENON Experiment (#303)
Create your
podcast in
minutes
It is Free
Sasquatch Chronicles
The Confessionals
Radiolab
Sasquatch Odyssey
Science Friday