During the formation of the Solar System Mars, the fourth planet from the Sun, was repeatedly struck by planetesimals (these are small protoplanets no larger than 1,200 miles in diameter). A few became moons, such as with Phobos and Deimos (the moons of Mars).
Simulating this bombardment activity, using a combination of materials examination and computer modelling, has enabled scientists to make a new estimate as to how hold Mars is (or at least when the planet began to form). the experiments involved the mixing of materials of a similar nature to Mars and the hunks of space matter, recreating the impacts.
The research also has implications for scientists who study the history of Earth. To date some 61,000 meteorites have been found on Earth, and of these around 200 are assumed to be of Martian origin, ejected from Mars as the result of the early collisions from the planetesimals.
According to lead researcher, Dr. Simone Marchi, from the Southwest Research Institute: “Based on our model, early collisions produce a heterogeneous, marble-cake-like Martian mantle. These results suggest that the prevailing view of Mars formation may be biased by the limited number of meteorites available for study.”
From the modelling, the researchers have indicated that instead of the prevailing view that Mars was formed some 2-4 million years after the Solar System began to form, the large, early time-point collisions support the view that Mars was formed over a far longer timescale of up to 20 million years. This is evidence from an assessment of the tungsten isotopic balance, drawn from the materials based models. This approach allows an assessment of heterogeneous mixture of materials found within the early Martian mantle.
The research has been published in the journal Science Advances. The research paper is titled “A compositionally heterogeneous Martian mantle due to late accretion.”
