Alex McColgan
speaker
29,581 appearances
105 recordings
1 series
first heard Nov 2024
last heard yesterday
Alex McColgan’s voice in public audio — every appearance, attributed to the second.
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recordings per month · last 12 monthsRecordings per month over the last 12 months — 69 in all, peaking in Aug 2026 with 11.
Appearances
The spacecraft detected a turbulent boundary layer at the edge of the magnetosphere, packed with particles spanning a wider energy range than anything ever previously recorded at Mercury.
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And more intriguingly, it found energetic, hot ions trapped near Mercury's equator, forming a ring current.
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But there's a problem.
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Given how small and compressed the magnetosphere is, a ring current like this shouldn't be possible here.
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On Earth, ring currents exist tens of thousands of kilometers above the surface, where there's enough space for particles to drift in stable loops.
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At Mercury, since the magnetosphere is so small and compressed against the planet on the sun facing side.
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The ring current would have to sit just a few hundred kilometers above the surface.
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But in this position, the particles don't have enough room to complete a stable orbit around the planet before crashing into it or getting swept away by the solar wind.
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So whether this ring is complete or partial is still being debated.
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But Beppi Columbus's findings could rewrite our understanding of how magnetospheres can look on rocky worlds close to their stars.
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It's also turned out that this finding could be key to understanding planets beyond our own solar system too.
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As our exoplanet catalogues have grown over the last decades, astronomers have started noticing something striking.
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There seems to be a whole class of rocky worlds that share Mercury's enormous iron-rich core, making up a disproportionate fraction of the planet's total mass.
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They're called Super Mercuris, and we think they're quite rare, but we've identified a few already, like the two orbiting the same star, HD 23472, 127 light years away.
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Because Mercury's magnetosphere is so compressed, it sits at the extreme end of what a planetary magnetic field can look like.
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That makes it ideal for stress testing our models and understanding how much protection a magnetosphere can afford, or how it gets stripped away over time.
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Changing our understanding of this would redefine how close to a star the habitable zone of exoplanet systems could be, and might open up far more candidate planets than we currently consider, some of which might even have water on their surface.
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Speaking of which, remember those freezing cold craters on Mercury's North Pole?
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Well, we've suspected for a while now they might contain frozen water ice.
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Which seems incredibly counterintuitive for a planet scorching in the sun.
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Showing 2761–2780 of 29,581 · page 139 of 1480
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