Unusual glassy spheres scattered across the Australian desert provide evidence of an ancient meteorite impact previously unknown to scientists. A recent study led by geoscientist Anna Musolino from Aix-Marseille University in France identified tiny glass beads in South Australia as a unique impact-melt composition not seen anywhere else on Earth.
These newly named ananguites are believed to have formed from a colossal impact event approximately 11 million years ago. Despite the impact’s scale, no crater has been found associated with this event, even though the mineral traces have survived in detectable quantities over millions of years.
"These glasses are unique to Australia and have recorded an ancient impact event we did not even know about," says geochronologist and geochemist Fred Jourdan of Curtin University in Australia.
"They formed when an asteroid slammed into Earth, melting surface rock and scattering debris for thousands of kilometres. These tiny pieces of glass are like little time capsules from deep in our planet's history."
"What makes the discovery even more intriguing is that, although the impact must have been immense, scientists are yet to locate the crater."
The desert regions of southern Australia are covered with these small glass beads, known as tektites, which were formed by the intense heat and pressure from the meteorite impact.
This discovery not only expands the catalog of known ancient impacts but also challenges scientists to explain the absence of a crater for such a massive event.
Author's summary: Unique glass spheres in Australia reveal a massive, 11-million-year-old meteorite impact with no discovered crater, offering new insights into Earth's impact history.