MemberSeptember 23, 2021 at 7:27 am
Meteorites are time capsules that illuminate the era of planet formation. The solar system formed from a cloud of interstellar gas and dust that collapsed under its own gravity. Particles within the resulting protoplanetary disk collided and stuck, forming ever larger planetesimals, which became the parent bodies of the meteorites found on Earth.
Meteorites come in different flavors. Depending on whether iron or silicates dominate, meteorites are traditionally classified as iron, stony, or stony-iron. Composition also depends on whether the meteorites originate from bodies that underwent melting, or whether the parent body was unmelted and therefore more pristine. By these classifiers, Nedagolla is an ungrouped iron meteorite.
But one can also look at isotopes. Isotopes are elements with the same number of protons but a different number of neutrons, and they can carry a lot of information, including the time of a rock’s formation.
“About 10 years ago, the community realized that there is an isotopic dichotomy in meteoritic material,” says graduate student Fridolin Spitzer (University of Münster, Germany), who was first author of the new study. Cosmochemists thus use isotopes to classify meteorites of all sorts, regardless of their chemical composition, as either non-carbonaceous chondrite (NC) or the carbonaceous chondrite (CC). (These groups were initially differentiated by the amount of carbon, but now the terms are used more generally.)
There is only one exception: “Nedagolla is the first one that does not consistently fall into one of the two categories but seems to fall in between,” says Spitzer.
Scientists suspect that the two isotope classes formed in two different parts of the protoplanetary disk: The NCs in the disk’s inner part and the CCs in the outer solar system, beyond the Jupiter´s orbit. So where does that put the Nedagolla meteorite?
MemberSeptember 24, 2021 at 4:19 pm
It is good to know about beginning of Earth.