The heart of Mars: harder than we thought
It seems that our red neighbor is not as soft inside as some believed. In a plot twist worthy of a scientific soap opera, a team of researchers, led by China, has come to tell us that the core of Mars is, in reality, a massive block of solid metal. Remember all those previous studies that talked about a liquid and emotional heart? Well, throw them in the cosmic recycling bin. The revelation, published in the prestigious journal Nature, is based on the last seismic rattles captured by NASA’s InSight module before it hung up its gloves in 2022. How appropriate that it decided to send this data just before its retirement, right? Almost as if he had planned it.
Poor InSight, stuck on a boring equatorial plain since 2018, spent its last days listening to the planet growl. He recorded more than 1,300 Marsquakes, of which 23, mostly of low intensity (because even when it comes to shaking, Mars is mediocre), were chosen to dethrone the previous theory. The epicenters of these planetary sobs were at a respectable distance from the lander, between 1,200 and 2,360 kilometers. Because, of course, the most crucial data always comes from afar, making the work of scientists even more… interesting.
A metal cake with solid filling
The delicious new theory suggests that Mars is like a cosmic bonbon: an outer shell of molten metal surrounding a solid inner core. This hard heart extends from the very center of the planet to a radius of approximately 613 kilometers. The liquid outer core surrounds it up to about 1,800 kilometers from the center. The likely composition is iron and nickel, with perhaps a touch of oxygen for flavor, much like that of Earth. What a coincidence! Although, as lead researcher Daoyuan Sun points out, perhaps it is just that, a coincidence. Let’s not think that we are special.
Sun of the University of Science and Technology of China speculates that crystallization of this nucleus may have started in the past and may continue today. Because in planetary evolution, everything is an eternal “work in progress.” What is not so clear is whether the outer core is a pure liquid or whether it has a pasty transition zone, a kind of cosmic custard, between the solid interior and the liquid exterior. What a crucial and yet delightfully absurd detail to investigate.
But not everyone is willing to celebrate with confetti. Nicholas Schmerr of the University of Maryland, who was not part of the study, uttered one of those phrases that journalists love: the questions about the Martian core “are far from resolved.” In other words: “Guys, this is just the beginning, don’t get too excited.” And he has a point. With InSight out of action, there will be no new recordings of seismic activity. We ran out of our microphone on the Martian soil, so we have to make computer models and speculate a lot.
Schmerr insisted that an entire network of seismographic stations is needed to unravel the remaining mysteries. Because a single probe is like trying to understand a conversation by listening to only one word out of ten. Sun agreed that more detailed models are needed to get a clearer picture of core formation and, more intriguingly, what it tells us about the history of the extinct Martian magnetic field.
Ah, yes. The magnetic field. Or the lack thereof. Schmerr suggested that the current absence of this protective shield on Mars could be due to the slow crystallization of its solid core. Wow, maybe the planet took its sweet time solidifying and lost its inner magnet along the way. A lesson for everyone: procrastination has consequences, even on a planetary scale.
What did you think of this trip to the center of Mars? Share it on your social networks and cause an earthquake of opinions! And be sure to explore our science section for more absurdly fascinating revelations about the universe.
