Drift through the closest exoplanet humanity has ever measured. Four point two four light-years from here, in the constellation Centaurus, a small rocky world orbits a flaring red dwarf star every eleven days. When Proxima Centauri b was first announced, it was the great hope for a second Earth. The closest potentially habitable planet ever discovered. A nearby world that future generations might send probes to within a single human lifetime. But the James Webb Space Telescope just looked again, with sharper instruments and longer integration time than the original observations, and what it found is worse than anyone hoped. The atmosphere may not be there at all. The flare radiation may have stripped it long ago. The dream of a nearby second Earth is being quietly retired by the same telescope that confirmed its existence. Tonight, we explore the original 2016 discovery, the 2024-2026 JWST follow-up campaign, atmospheric escape modelling around M-dwarf flares, the tidal locking constraints, and what these findings mean for the broader population of habitable-zone planets around the most common stars in the galaxy. If you enjoyed this exploration of the deepest mysteries of the cosmos, subscribe for more sleep-friendly journeys through space. Sources: Anglada-Escude et al 2016 - Original Proxima Centauri b discovery via radial velocity, Queen Mary University of London ESPRESSO Collaboration 2020-2024 - Refined Proxima b mass measurements, ESO JWST MIRI 2024-2025 - Proxima Centauri b thermal observation campaigns, NASA Goddard Kreidberg et al 2019 onwards - Hot rocky exoplanet atmosphere characterisation methodology Suissa et al 2020 - Proxima Centauri b atmospheric escape modelling Garraffo et al 2016 - Proxima Centauri stellar wind environment modelling MacGregor et al 2018 - ALMA detection of giant Proxima Centauri flare Howard et al 2018 - Proxima Centauri superflare observations Tilley et al 2019 - Stellar flare impact on exoplanet atmospheres Loyd et al 2018 - MUSCLES Treasury Survey of M-dwarf UV environments Tarter et al 2007 - Habitable zone around M-dwarfs review Kasting et al 2014 - Habitable zone definitions and M-dwarf constraints Cohen et al 2024 - Tidally locked exoplanet atmospheric dynamics Breakthrough Starshot mission concept - Future Proxima b probe proposal
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the absence of evidence is not evidence of the absence!! say what again!!
Proxima doesn't transit for web to observe it. This is such a BS. Bye
3 hours of repeating maybe a dozen things. wow
Wait this is almost 3 hours. Nevermind.
The planet that might not be inhabitable and breathable.
We will never travel there.