The Moon, the natural satellite of the Earth, may be more closely related to our planet than we think. Recent evidence has been pointing toward a direct association between the Moon and the Earth. The lunar body that orbits our planet is apparently made of constituents of the Earth in part, coming into existence as a result of a cataclysmic collision early in the history of our planet.
Until now, many theories were not in place with this new discovery of the celestial link. Recently, in a study published in the journal Science, a team of German researchers have claimed to have found evidence to support the creation of the moon through a collision between the Earth and another planet-sized object 4.5 billion years ago.
The German scientists on the team studied Moon rocks gathered by astronauts nearly a half-century ago in the Apollo 11, 12 and 16 missions. Daniel Herwartz, an isotope geochemist at the University of Cologne in Germany and a member of the study team, along with his colleagues carried out an examination on oxygen isotopes because planets and moons have a distinct oxygen fingerprint that records the exact environmental conditions in which they were born.
The method involved the usage of an extremely precise laser to measure oxygen isotopes in a range of Earth rocks, meteorites and three lunar samples gathered by the Apollo astronauts. The study confirmed 12 parts per million more oxygen-17 in the Moon rocks as opposed to the Earth rocks. “It’s a tiny difference, that’s why it hasn’t been seen before,” says Herwartz.
An analysis of various kinds of oxygen atoms led to the conclusion that Moon rocks, Apollo Era rocks, have a different makeup than Earth rocks, therefore, containing material from the planet-sized object that collided with Earth. The study suggests that the Moon may comprise of matter from the Earth and the object in equal proportions.
“Earth’s Moon is distinct among the >150 moons of our solar system,” the authors of the ground-breaking study point out. “Most other planets are either captured planetesimals, or they formed along with the planet in a common accretion disc.”
The Moon of our planet was the result of an encounter with a smaller, Mars-sized proto-planet Theia, as a consequence of which chunks of the Earth and Theia went flying, eventually combining into the Moon. The study hints at the proto-planet being chemically similar to a class of meteorites called enstatite chondrites. Those meteorites are similar to Earth in terms of oxygen and Theia may not, thus, have left a major imprint in the Moon’s chemical composition of the Moon.
However, many of the accepted models suggest that the Moon is made mostly of Theia’s remains, that is, 70% to 90%.
Through the discovery of Theia’s contribution in the creation of the Moon, theorists have an opportunity at hand to learn more about the long-deceased proto-planet.