New Data provides insight into early history of Mars and Earth

A team of researchers have been discussing the possibility that terrestrial planets such as Earth and Mars could have remained in a molten state for tens of millions of years. This hypothesis means that these planets cooled at much slower rates than originally thought. New data indicates that the early stages of inner planets encompass complex mechanisms that are currently misunderstood. Evidence for a slow cooling process has been discovered on Mars, but evidence on Earth has been erased thanks to erosion and other natural processes.

Instead of slow cooling Magma oceans, scientists are thinking that Mars once contained an insulating ‘primitive atmosphere’ of hydrogen that was removed by impacts when the planet was just 100 million years old. This evidence was obtained by measuring the composition of the neodymium isotope in nine meteorites from Mars, called shergottites. These unique meteorites were once lava that melted deep in the interior of Mars and then erupted onto the surface. Impacts on Mars uncovered these rocks and launched them into space, where some eventually collided with Earth. By tracing radioactive decay, the team of researchers discovered that the shergottites formed at two different times, about 4,560 million years ago, and 110 million years after the solar system began to condense. This means that the cooling process extended for a much longer period than originally estimated.