Earth share similar chemical origin with early planetary objects

Earth and other planetary objects formed in the early years of the solar system share similar chemical origins, a new study has found, contradicting the accepted wisdom held by scientists for decades.

With data uncovered through thermal ionization mass spectrometry, researchers led by Audrey Bouvier from University of Western Ontario in Canada demonstrated that the Earth and other extraterrestrial objects share the same initial levels of Neodymium-142.

Neodymium-142 is one of seven isotopes found in the chemical element neodymium which is widely distributed in the Earth’s crust and most commonly used for magnets in commercial products like microphones and in-ear headphones.

In 2005, a small variation in Neodymium-142 was detected between chondrites, which are stony meteorites considered essential building blocks of the Earth, and terrestrial rocks.

These results were widely interpreted as an early differentiation of the interior of the Earth (including the crust and mantle) and these chondrites within the first 30 million years of its history.

These new results show that these differences in Neodymium-142 were in fact already present during the growth of Earth and not introduced later, as was previously believed.

“How the Earth was formed and what type of planetary materials were part of that formation are issues that have puzzled generations of scientists,” said Bouvier.

“And these new isotopic measurements of meteorites provide exciting answers to these questions about our origins and what made the Earth so special,” he said.

By using vastly improved measurement techniques, researchers deduced that different meteoritical objects found in the solar system incorporated the elements neodymium (Nd) and samarium (Sm) but with slightly different isotopic compositions.

These variations in stable isotopes also show that the solar system was not uniform during its earliest times and that materials formed from previous generations of stars were incorporated in various proportions into the building blocks of planets.

The findings were published in the journal Nature.