Alex McColgan
speaker
29,301 appearances
104 recordings
1 series
first heard Nov 2024
last heard 21 Sep
Alex McColgan’s voice in public audio — every appearance, attributed to the second.
Trend
recordings per month · last 12 monthsRecordings per month over the last 12 months — 68 in all, peaking in Aug 2026 with 11.
Appearances
By analysing the material in the peak ring, we can get a better idea of what Mercury's subsurface is made of, which could inform our theories on how rocky planets and exoplanets form.
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But this wasn't the only strange surface marking, Beppi Colombo observed.
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Three months later, on the first of December 2024, it swung by the planet again, and for the first time in history, captured its surface in mid-infrared light.
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And what it revealed completely flipped a decades old assumption about Mercury on its head.
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Researchers use the Mercury Radiometer and Thermal Infrared Spectrometer or MERTIS to scan the surface of the planet in an attempt to better understand what it's made of.
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See, when a material is bombarded with mid-infrared wavelengths, the chemical bonds within the molecules absorb specific frequencies of this light, causing them to vibrate in distinct ways.
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Because every molecule has a unique set of bonds, the resulting absorption pattern acts as a definitive chemical fingerprint which can be cross-referenced with known substances.
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So, for example, the chemical fingerprint of graphite.
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While the chemical fingerprint of sulfur looks like this.
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Mertis operates at wavelengths between 7 to 14 micrometers, the ideal range for fingerprinting rock forming minerals.
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Harold Hiesinger, the Mertice's principal investigator from the University of Munster, is optimistic.
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With Murtis, we are breaking new ground and will be able to understand the composition, mineralogy, and temperatures on Mercury much better, he says.
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And the image the team got back after analysis did not disappoint.
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The first thing the team noticed was the striking variation in the surface brightness.
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Some patches of Mercury's surface shine more intensely than others, shaped by differences in temperature or roughness.
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These variations could give us clues to how different parts of the planet evolved or how their geological activity might have differed in the past.
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Some variations are, of course, caused by differences in mineral composition, many of which differ greatly from anything we've seen on our home planet.
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Since Mercury exists in an oxygen poor environment, it has what researchers call a reduced geochemistry.
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In such environments, elements behave in ways that have almost no parallel on Earth.
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Mercury's rocks are rich in sulfur and other elements that flourish without oxygen, forming unusual minerals like iron and calcium sulfides.
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Showing 2381–2400 of 29,301 · page 120 of 1466
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