Quakes by InSight indicate Mars’ interior is active

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Cerberus Fossae

The first seismic results from InSight’s seismometer now show that the interior of Mars is active, with regular moderately-sized quakes.

The Seismic Experiment for Interior Structure (SEIS) instrument – a seismometer developed by an international consortium under the leadership of the French space agency CNES – recorded a total of 174 seismic events between February and September 2019. Twenty of these marsquakes had a magnitude of between three and four. Quakes of this intensity correspond to weak seismic activity of the kind that occurs repeatedly on Earth in the middle of continental plates, for example in Germany on the southern edge of the Swabian Jura hills.

Although only one measurement station is available, models of wave propagation in the Martian soil have been used to determine the probable source of two of these quakes. It is located in the Cerberus Fossae region, a young volcanic area approximately 1700 kilometres east of the landing site.

Cerberus Fossae is a land of cracks and linear depressions located between the giant volcanoes, Elysium Mons to the north and Olympus Mons to the east. It is believed those fissures were caused by the rise of those volcanoes, stretching the crust and cracking it.

This new data from InSight strengthens this theory.



  • wodun

    They should still be called earthquakes not marsquakes. People take things too literally. The term doesn’t refer to the “Earth” but rather the movement of the ground and how it feels. Keeping these terms as we move off our mother planet will help us remember where we came from and in touch with our humanity.

    Oh, but wait, humanity has man it in and it excludes… It doesn’t exclude anyone. Words with man in them don’t necessarily mean male. Gender is a social construct except that gender neutral words must but be stripped of their meaning to create differences where there aren’t any.

  • Edward

    wodun wrote: “Words with man in them don’t necessarily mean male.

    I once wondered why some people got upset about words that have “man” in them. “Woman” is specific about the sex that is being identified; it is “man” that is ambiguous, and therefore inferior for specifying one sex rather than another. For example, an chairman can be either male or female, but a chairwoman can only be female. It all began to make sense to me shortly after people started to use the word “gender” when they meant “sex.” “Gender” refers to things or the words used for things. It does not refer to people, who possess the attribute of sex, not gender. An example is that a ship is feminine, as in “she sailed with the tide.”

    The English language has been poorly taught for several decades, now. It is another example of the ill effects of political correctness. To illustrate my point about ill effects of political correctness, FaceBook has at least 58 “genders” (as though people are things, not humans or animals):

    Unfortunately, my self-identified “gender,” deity, is not among them. Maybe next year.

    Sorry, Robert, for going so far off topic.

    Back on topic: the English language. Generally, when “earth” is not capitalized, it refers to the ground or soil, not the planet. This means that “earthquake” is still appropriate when talking about other worlds, such as Mars.

    On the other hand, “marsquake” or “Marsquake” may have a more romantic or adventurous ring to it.

    On the third hand (the gripping hand), Alpha-Ceti-Sixquake many not have such a ring.

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