Astronomers announce the discovery of the first ever “Boomerang meteorite” – a rock that originated from Earth, was flung into space and later returned.
The meteorite, NWA 13188, was discovered in the Sahara Desert, and scientists at Aix-Marseille University in France conducted a new analysis, and found that it has the characteristics of our planet.
The body contains a composition found in the earth’s crust and volcanic rocks, but also those elements that appear only when exposed to active cosmic rays in space. Researchers believe the rock was propelled into space by an asteroid impact about 10,000 years ago.
The rock in question was discovered by meteorite hunters in 2018 in Morocco, prompting scientists to name it North West Africa (NWA). The analysis, which was led by Jérôme Gacheca, determined that the rock has an ‘extensive basaltic andesite composition’ found in igneous rocks all over the world.
It is also dominated by plagioclase, an aluminum-bearing mineral and pyroxene, a dark-colored mineral due to its composition, which scientists said sparked the argument that the “space rock” is not a meteor at all.
However, some elements have been changed into light forms, which is only possible if rocks interact with cosmic rays in space.
One piece of evidence for the rock returning to Earth from space says that the measured concentrations of these variable elements, known as isotopes, are too high to be explained by Earth-related processes.
Gacheca and his team found traces of detectable isotopes such as beryllium-3, helium-10 and neon-21 in NWA 13188, Space.com reports.
The researchers also identified a fusion crust layer on the rock, which forms when meteorites rise through Earth’s atmosphere and travel to Earth.
This scenario matches the most recent definition of a meteorite: “Material released from a celestial body that achieves an independent orbit around the Sun or some other celestial body, and finally reconstituted by the original body, should be considered a meteorite. The difficulty, of course, is to prove that this could It happened, but terrestrial rocks exposed to cosmic rays and an evolving fusion crust should be considered as a possible terrestrial meteorite.”
