Oct 22, 2025 05:56 PM
https://www.universetoday.com/articles/s...roto-earth
EXCERPTS: Earth has a long, 4.5 billion history full of momentous twists and turns. Multiple prominent events played leading roles in Earth's story. One of them is the catastrophic impact with another planetesimal early in Earth's history that not only created the Moon, but altered Earth's chemistry forever.
Isotopic evidence tells much of Earth's story, and scientists scour the Earth in search of the oldest rocks in existence to study their isotopes. Some of the planet's oldest rocks are in Greenland, Canada, and South Africa, and those rocks play a central role in new research into the proto-Earth, the Earth that existed prior to the Moon-creating impact. The isotopic ratios in those rocks illuminate Earth's story.
[...] "Earth’s bulk composition has elemental and isotopic characteristics that cannot be fully reconciled with a mixture of known primitive meteorite compositions," the authors write in their research, alluding to the fact that Earth formed from the same material as meteorites. "One potential explanation for this is that the proto-Earth accreted materials with isotopic signatures distinct from those accreted after the Moon-forming giant impact."
Earth was once a magma ocean, a ball of molten lava too hot to cool and solidify. This was during the Hadean eon, and at some point during the Hadean, a massive protoplanet about the size of Mars slammed into Earth. The protoplanet was called Theia, and this impact gave birth to the Moon. The impact also delivered a lot of material to Earth, and it had a slightly different chemistry than the Earth.
[...] “In that work, we found that different meteorites have different potassium isotopic signatures, and that means potassium can be used as a tracer of Earth’s building blocks,” lead author Nie explained in a press release.
[...] All together, it shows that the ancient rock samples are most likely remnants of the proto-Earth that have somehow survived for billions of years. By extension, any materials that display the same potassium-40 deficit are likely proto-Earth relics.
“This is maybe the first direct evidence that we’ve preserved the proto Earth materials,” sa Nie. “We see a piece of the very ancient Earth, even before the giant impact. This is amazing because we would expect this very early signature to be slowly erased through Earth’s evolution.” (MORE - missing details)
EXCERPTS: Earth has a long, 4.5 billion history full of momentous twists and turns. Multiple prominent events played leading roles in Earth's story. One of them is the catastrophic impact with another planetesimal early in Earth's history that not only created the Moon, but altered Earth's chemistry forever.
Isotopic evidence tells much of Earth's story, and scientists scour the Earth in search of the oldest rocks in existence to study their isotopes. Some of the planet's oldest rocks are in Greenland, Canada, and South Africa, and those rocks play a central role in new research into the proto-Earth, the Earth that existed prior to the Moon-creating impact. The isotopic ratios in those rocks illuminate Earth's story.
[...] "Earth’s bulk composition has elemental and isotopic characteristics that cannot be fully reconciled with a mixture of known primitive meteorite compositions," the authors write in their research, alluding to the fact that Earth formed from the same material as meteorites. "One potential explanation for this is that the proto-Earth accreted materials with isotopic signatures distinct from those accreted after the Moon-forming giant impact."
Earth was once a magma ocean, a ball of molten lava too hot to cool and solidify. This was during the Hadean eon, and at some point during the Hadean, a massive protoplanet about the size of Mars slammed into Earth. The protoplanet was called Theia, and this impact gave birth to the Moon. The impact also delivered a lot of material to Earth, and it had a slightly different chemistry than the Earth.
[...] “In that work, we found that different meteorites have different potassium isotopic signatures, and that means potassium can be used as a tracer of Earth’s building blocks,” lead author Nie explained in a press release.
[...] All together, it shows that the ancient rock samples are most likely remnants of the proto-Earth that have somehow survived for billions of years. By extension, any materials that display the same potassium-40 deficit are likely proto-Earth relics.
“This is maybe the first direct evidence that we’ve preserved the proto Earth materials,” sa Nie. “We see a piece of the very ancient Earth, even before the giant impact. This is amazing because we would expect this very early signature to be slowly erased through Earth’s evolution.” (MORE - missing details)