The meteorite is 4.6 billion years old and is still rocking the solar system dating scene • Log

At 4.6 billion years old, Erk Chek 002 is the oldest known meteorite on Earth. New analysis of its composition helps us understand the early solar system and help date other space rocks.

A research team led by Australian National University PhD candidate Evgenii Krestianinov has found aluminum-26 (26Al) in a magnesium alloy – a space rock discovered in 2020 in the Erg Chech region of the Sahara Desert in Algeria. .

Radioisotopes are known to have been the main source of heat for the melting of early planets. The researchers argue that its discovery in Erk Chek 002 could help understand its early distribution within the early solar system.

Erk Chek 002 is an andesitic achondrite, one of the oldest meteorites on Earth. A vexing question for researchers is whether 26Al was evenly distributed throughout the early solar system, as it is important for determining the ages of other meteorites.

To find that out, they had to look for lead isotopes in the rock, which revealed that it was about 4.566 billion years old. Comparing the data with analyzes of other „very old” meteorites, they concluded that the isotope distribution within the early solar nebula was uneven, possibly related to the late infall of stellar material containing newly synthesized radioactive elements.

„Our analysis, combined [earlier] „The published data reveal that the initial 26Al/27Al in the raw material of this achondrite was significantly higher than that of a well-preserved and precisely dated achondrite,” the researchers said. A sheet Published in Natural communication This week.

The results suggest that other relative ages based on aluminum-magnesium alloy (Al-Mg) alone should be re-evaluated.

„Developing a general approach to isotopic dating with Al-Mg and other extinct isotope chronometers. [radioactive elements] „This will allow us to develop more accurate and reliable age data for meteorites and asteroids and planetary objects, improving our better understanding of the formation of our Solar System,” the researchers said.