Rock Found in Field Turns Out to Be 4.6GY Old Meteorite

Keith_McClary said:

Summary:: Rock Fragment Found in Field Turns Out to Be Ancient 4.6-Billion-Year-Old Meteorite

A small fragment of rock found lying in a field in Gloucestershire in the UK may not have looked like much to the casual passerby ...

Did there happen to be a meteorite expert wandering in the Gloucestershire field?

Its age and mineral content hint that the rock originated in our early solar system from the crust of a protoplanet — a large, rocky body in the process of developing into a planet, according to a new study.

The meteorite, called Erg Chech 002 (EC 002), is likely a rare surviving chunk of a lost baby planet that was destroyed or absorbed by bigger rocky planets during our solar system's formation.

Pieces of EC 002 were found in Adrar, Algeria, in May 2020, and the fragments were "relatively coarse grained, tan and beige," sporadically studded with crystals that were "larger green, yellow-green and less commonly yellow-brown," according to a description by the Lunar and Planetary Institute (LPI).

EC 002 is an achondrite, a type of meteorite that comes from a parent body with a distinct crust and core, and lacks round mineral grains called chondrules, according to the Center for Meteorite Studies at Arizona State University.

Radioactive versions, or isotopes, of aluminum and magnesium indicated that the meteorite's parent was an ancient body dating to 4.566 billion years ago, and EC 002's chemical composition revealed that it emerged from a partly-melted magma reservoir in the parent body's crust. Most rocky meteorites come from sources with basaltic crusts — rapidly cooled lava that is rich in iron and magnesium — but EC 002's composition showed that its parent's crust was made of andesite, which is rich in silica.

Understanding how Aluminum-26 was distributed as the planets were forming around 4.6 billion years ago is thus important to building a picture of how the rocky inner planets of the solar system evolved. Additionally, because Aluminum-26 decays to Magnesium-26, a stable form of Magnesium, it can be used as a dating system for space rocks.

To determine the age of Erg Chech 002 as 4.566 billion years old, the team measured the amounts of lead isotopes within it, but this, ironically, could have provided scientists with a way of improving another dating strategy for similar meteorites.

Astronuc said:

Another, but recent, story on Erg Chech 002 meteorite.

Keith_McClary said:

TL;DR Summary: Rock Fragment Found in Field Turns Out to Be Ancient 4.6-Billion-Year-Old Meteorite

A small fragment of rock found lying in a field in Gloucestershire in the UK may not have looked like much to the casual passerby ...

I'm curious how this was found, if not by a "casual passerby". Did there happen to be a meteorite expert wandering in the Gloucestershire field?