Inside Mars revealed by Insight

International Group of Astronomers NASA’s Insight mission Published three articles in the magazine Science It shows how far we have come Viking works of the 1970s, The first person to begin active exploration of Mars on Earth. Carl Sagan Unfortunately it is no longer possible to know (or comment on) the results of these articles, which suggests that we now have as complete and accurate a picture as possible of the internal structure of Mars.

Specialized astronomers Geography And Mars geophysics has already been able to achieve some results before many other fields Gravity And the Martian landscape, relating the data in these areas to the mineral and cosmological information provided by the study Mars meteorites (As in planetary science Astronomy, The world’s microscopic system and its macroscopic system maintain strong causal links). Thus known as thickness Top tile Must have been 30 to 100 kilometers from the Red Planet. But we could not go far with other data on the deep structure of Mars, we determined that there should be a maximum of one nucleus, with a radius estimated at 1,400 to 2,000. Kilometers.

Articles published Science By Insight Collaboration Top tile, The Code And this Core In March. The first Martian crust reports several physical and chemical suspensions. As explained A CNRS news release, First 10 km depth and Geologists Martians argue that this reflects the presence of very atmospheric rocks, resulting in a much older fluid cycle. Below, a slightly altered geological structure is 20 km. Around will be with a second pause, then a third, less marked, 35 km.

Studies by gravity, magnetic field and seismic, inland geophysicists

A unique analysis Seismic waves Made possible by experience ஆறு (Seismic testing for interior structures), Three types Seismic measurements, Allowing us to conclude that there is now an iron center on Mars Liquid Its radius ranges from 1,790 km to 1,870 km and contains The light elements are like the center of the earth. But, because there is nothing but one Fossil smooth magnetic field on Mars, This fluid is not in the center Nowadays the landscape is equivalent to geomechanics.

On the other hand, the Code Mars appears to have a single mineral crust similar to the Earth’s crust. But the analog of the lower mandible dominates Bridgemanite Seems to be absent, which causes effects on the temperature conditions of Mars’ mantle. As explained Philip Lagnonne In an article Conversation France, Professor and geologist at the Paris Institute of Globe Physics (IPGP) in the field of geophysics and astronomy Cheese’s chief investigator at the Institute of Physics: “ If it had been on Mars, such a layer would have been “elevated”. Convection Therefore Volcano, Especially in the first 500 million years. »

We come to these conclusions especially trying to stick with thousands of observations Digital models It’s like searching for the exact characteristics of a musical instrument, the Martian shield and center, depending on many adjustable parameters, like comparing the sound produced by an entire family and listening to it without looking at it. This is called Resolution An inverse problem in terms of Physicists Mathematicians.

Let’s clarify all this a little bit.

Like our Blue Planet, there was a revolution in determining the internal structure of Mars Earth quake. Only at the beginning of the 20th century can we have a moving mindset for the pioneers of this science.^e Century, by placing its theoretical and practical sites with mechanical and electro-mechanical seismic measurements made possible the study of rocky planets in general, but also of such stars. சோலைல், Via Asteroid. Already at that time, they say they are smart Harold Jeffries, British geophysicist, astronomer and mathematician He was interested in determining the origin of the planets, so he used the Earth as the only laboratory of its time, to unravel the mystery of its universe, which would lead to a situation where seismic science would be hard to prove. Earth Core.

In both Earth and Mars, astronomers were initially able to rely on field research to determine their internal structures. Gravity These planets and their rotational movements, which continue today in conjunction with the study of seismic waves.

Distribution Thing Because the planets differ in density, the gravitational field must be internally outside the planets, thus making measurements gravimétrie Precise movements on the surface, and especially in studies Around the circular path The gravitational field created by these passes through valleys and bumps of symmetrical surfaces Stars, Made it possible to form ideas about what the surfaces of the Earth and Mars already obscure.

We can also take into account what we call it Tensor Of the momentRecession Of a planet, it also depends on the distribution of matter and the shape of a planet. Is injected into the popular Euler equations of a body Solid In rotation, it determines the axis of rotation of a planet subject to external gravitational forces, or, for example, changes in the material distributions of the event. Earthquakes, Will change over time. Thus, the study of the axial movements of the earth’s rotation, they are expressed in the form of exampleA slip from its geographic poles, Also proved invaluable in the presence of obstacles in the internal structure of our Blue Planet.

In the case Mission Insight, Here it is Nutrition And this Pioneer The axis of the Mars cycle used thanks to the tool Get up (Rotation and interior structure testing) Which provided pressures at the center of the planet.

Cheese, an exceptional seismometer

Today, more than 600 Martian earthquakes have been recorded and analyzed by an international team Tuesday Earthquake Service (MQS) of Insight Mission, they were chatting. Seismic data are monitored daily for one Mars year (approximately two Earth years) Cheese, which is an exceptionally high broadband seismometer Hand deposit Robotic Insight into the surface of Mars, a distant relative of seismic measurements once made Viking.

On Earth, there are thousands of stations to measure seismic waves, their types, arrival time,Energy Is relevant, so it can be used to detect the sources of seismic waves Triangle Go to the nature and distribution of rocks into the earth. In fact, depending on the nature of the rocks and their temperature conditions Pressure, Types of waves, their Frequencies Travel times are not the same.

In the case of Mars, there is only one station for recording seismic waves, and it is on the surface, unlike on Earth, where they are buried, so they recede from activity. Holes. Although Mars is weak and the seismic noise of Mars is just that, it is necessary to efficiently filter the recorded signals to consider only those that can speak inside Mars.

As Eric Beckler explains in the video below (6:50), cheese actually has three major seismic measurements. This makes it possible to reverse the direction of origin of particularly measured seismic waves. After all, astronomers have used transitions between different types of waves and their different frequencies and phase changes, whether they propagate on the surface or are reflected by inner layers, as they appear during arrival periods. Single Earthquake to illuminate the internal structure of Mars (see descriptions and graphics in addition to video Magazine CNRS).