London: Researchers have discovered minerals from 43 rare meteorites that landed on the Earth 470 million years ago, which challenge our understanding of the history and development of the solar system.
More than half of the mineral grains are from meteorites completely unknown or very rare in today’s meteorite flow, researchers said.
These findings mean that we will probably need to revise our current understanding of the history and development of the solar system, they said.
The discovery confirms the earlier hypothesis in which geology professor Birger Schmitz at Lund University in Sweden revealed that he had found what he referred to as an “extinct meteorite” – a meteorite dinosaur.
The meteorite was given the name Osterplana 065 and was discovered in a quarry outside Lidkoping in Sweden.
The term ‘extinct’ was used because of its unusual composition, different from all known groups of meteorites and because it originated from a celestial body that was destroyed in ancient times.
The discovery led to the hypothesis that the flow of meteorites may have been completely different 470 million years ago compared to today, as meteorites with such a composition no longer fall on Earth.
“The new results confirm the hypothesis. Based on 43 micrometeorites, which are as old as Osterplana 065, our new study shows that back then the flow was actually dramatically different,” said Schmitz.
“So far we have always assumed that the solar system is stable, and have therefore expected that the same type of meteorites have fallen on Earth throughout the history of the solar system, but we have now realised that this is not the case,” he said.
Schmitz noted that something so far unknown but of fundamental importance in the history of the solar system occurred nearly 500 million years ago.
The new study shows that it is possible to make highly detailed reconstructions of the changes that have occurred in the solar system, Schmitz said.
“We can now recreate late history of not only the Earth but of the entire solar system. The scientific value of this new report is greater than the one last summer,” said Schmitz.
In the search for the mineral grains (chromium oxides) that fell on Earth together with the meteorites, the researchers used different acids to dissolve several tonnes of sediment from the ancient seabed.
The chromium oxides were subsequently analysed to identify their composition and oxygen isotopes. This made it possible to determine from which type of meteorites the grains originated.