As per a research paper published in the Journal of Science in July 2021, researchers at ETH Zurich and the University of Zurich analysed the seismic data sent by InSight and derived many valuables clues about Mars. Since early 2019, researchers from ETH Zurich, Switzerland, have been recording and analysing the data of marsquakes sent by the InSight. This analysis enabled scientists to measure Mars’ crust, mantle, and core which will be helpful in understanding the formation and evolution of Mars along with the entire solar system. NASA’s InSight lander touched down on Mars on November 26, 2018. This was the first mission to explore Mars’ deep interior. It investigated processes that shaped the rocky planet, in the inner solar system.
The Findings
The scientists discovered that the crust of Mars near its equator is 15–47 km thick and contains a relatively high proportion of radioactive elements. It was found that Mars is a one-plate planet with a single continental plate, in contrast to Earth which comprises of seven large mobile plates. Due to this, the mantle of Mars is 400–600 km deep and two times thicker than that of the Earth. The Martian mantle is rich in minerals like Earth’s upper mantle. The seismological data revealed that the Martian mantle with the lithosphere of more solid rock contains more iron than the Earth’s.
The radius of Martian core is about 1,840 km. As the radius of the core has been ascertained, it will enable the scientists to calculate the density of the Martian core. The data confirms that Mars was probably completely molten before differentiating into crust, mantle, and core. The core contains a large proportion of lighter elements, in addition to iron and nickel, which include sulphur, oxygen, carbon, and hydrogen, and make up an unexpectedly large proportion. But the composition of the whole planet is not yet totally understood.
The study confirmed that Mars no longer had a magnetic field but it was not known how the internal dynamics of Mars led it to lose its active magnetic field and all surface water. This finding will give an idea as to whether and how these processes might be occurring on our planet.
Marsquakes
Marsquakes are tremors, similar to earthquake, on Mars. During an earthquake, energy is released in the form of primary as well as secondary waves, which propagate from the source in all directions. The same is true of marsquakes. The primary P waves oscillate in the direction of propagation, like sound waves in air. The secondary S waves oscillate transverse to the direction of propagation and are slower than P waves. Measuring the time difference between the arrival of the P and S waves at a certain location makes it possible to calculate the distance from that location to the quake’s epicentre.
Scientists are studying the seismic waves generated by marsquakes and with the new findings, they will be able to shed more light on the origin of the universe and the evolution of life process.
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