Mars Insight mission: NASA’s probe solves the mystery about the internal structure of Mars

How was Mars built inside? Is its core liquid or solid? Research deals with these questions for a long time. There are answers for NASA’s Mars InSight mission.

Zurich – Mars is the next planet Earth – yet the planet still holds many mysteries and secrets. One of these mysteries has now been solved: researchers have discovered what the interior of the Red Planet looks like. We know how the Earth is formed: it has a thin crust (hard rock), then follows the thick Earth’s mantle layer (sticky, heavy rock) and finally the Earth’s core, which is made of iron and nickel, with the outer core being liquid and the inner core being solid. But is it the same with other rocky planets?

The answer to this question was provided by the Mars mission “Insight”, in which several European organizations, as well as the US space agency NASA, are involved. “Seismic data confirm that Mars was once completely molten, and is now divided into a crust, mantle, and core, which are different from Earth,” explains Amir Khan of ETH Zurich in a call from the university.

How does it look inside? NASA’s Mars InSight mission helps with measurements

The Mars InSight mission has been exploring the Red Planet since the end of 2019. In contrast to NASA rovers like Curiosity or Perseverance, InSight is still standing, a lander that has activated a seismometer at its landing site in order to measure seismicity. . InSight has measured a total of 733 earthquakes on Mars so far, 35 of which have been evaluated for three studies that now show how the interior of Mars is structured:

NASA Insight mission: Mars core is bigger than expected

Science is particularly interested in the essence of Mars. “This study is a unique opportunity,” says Swiss researcher Simon Stahler (ETH Zurich), lead author of the research paper on the Martian core. “It took scientists hundreds of years to measure the Earth’s core; after the Apollo missions, it took forty years to measure the lunar core.” On the other hand, added Stehler, “Insight” only needed two years to measure the core of Mars.

Surprise for researchers: the core of Mars is 200 km larger than expected when the InSight mission was planned 15 years ago. With the help of the radius, the density of the core can now be calculated: “If the radius of the core is large, the density of the core should be relatively low,” says Staller. In addition to iron and nickel, the core should also contain significant proportions of lighter elements – for example, sulfur, oxygen, carbon and hydrogen. However, their share should be unexpectedly large, leading to the conclusion that the composition of Mars is not yet fully understood, according to a statement from ETH Zurich. However, one thing is now clear: the core of Mars is – as it is already believed – liquid.

Mars InSight mission measures earthquakes on the Red Planet – it reveals the internal structure

In order to arrive at these findings, the researchers looked at the seismic signals recorded by Insight. Martian earthquakes take place in waves – if the wave’s path or speed changes, inferences can be drawn about what material the wave is moving through.

NASA’s Insight mission measures earthquakes — and researchers are waiting for a ‘big’ earthquake

So far, only Martian earthquakes have been evaluated with magnitudes between 3.0 and 4.0, but the Mars seismometer measures new ones every day Scientists hope to detect an earthquake greater than 4.0 on the Richter scale before the end of the InSight mission. “A bigger earthquake will make the search easier,” says Mark Banning of NASA’s Jet Propulsion Laboratory and co-author of the study on Mars’ crust.

The new findings regarding the internal structure of Mars aim to help researchers learn how rocky planets – including Mars, Earth, Venus and Mercury – formed. Studies too Mars CrustAnd -Rack And – Kern Featured in Science magazine. (Tania Banner)