Posted on 04/25/2023 7:50:36 AM PDT by Red Badger
An artist’s depiction of Mars' core and the paths taken by the seismic waves as they traveled through the planet’s core. Image courtesy of NASA/JPL and Nicholas Schmerr
The InSight mission’s seismometer, coated by years of Martian dust, captured recordings of seismic events from the far side of the planet. NASA's InSight Mars lander acquired this image of the area in front of the lander using its lander-mounted, Instrument Context Camera. Photo courtesy of NASA
April 25 (UPI) -- Scientists have confirmed that Mars' core is liquid as seismic wave measurements have given valuable first-time clues about how the Red Planet was formed.
The findings, published in the Proceedings of the National Academy of Sciences, show Mars' core is a completely liquid iron-alloy core with high percentages of sulfur and oxygen, unlike Earth's core, which is a combination of a liquid outer core and a solid inner core.
It took an international research team, which included University of Maryland seismologists, to measure Mars' core properties using seismic data from the NASA InSight lander mission, which ended in December.
"In 1906, scientists first discovered the Earth's core by observing how seismic waves from earthquakes were affected by traveling through it," UMD Associate Professor of Geology Vedran Lekic, and second author of the paper, said in a statement.
"More than a hundred years later, we're applying our knowledge of seismic waves to Mars. With InSight, we're finally discovering what's at the center of Mars and what makes Mars so similar yet distinct from Earth," Lekic added.
Researchers tracked InSight's seismic data, which detected two distant events on Mars including a Marsquake and a meteor strike.
"Nobody's ever seen before a seismic wave going through Mars' core," said seismologist Jessica Irving from the University of Bristol in Britain. "We waited for more than 900 days for one quake on the far side," she said. Then "24 days later, there was a meteorite impact."
Scientists measured the time it took for those seismic waves to travel through Mars and compared them to waves that stayed in the mantle. With that information, they were able to estimate the density of the planet's core and determine its chemical makeup of sulfur and oxygen.
"You can think of it this way; the properties of a planet's core can serve as a summary about how the planet formed and how it evolved dynamically over time," said UMD Associate Professor of Geology Nicholas Schmerr, who was also a co-author of the paper.
While the core reveals Mars does not currently have a magnetic field, traces of magnetism in Mars' crust reveal it may have at one time, according to Schmerr.
"The uniqueness of Earth's core allows it to generate a magnetic field that protects us from solar winds, allowing us to keep water. Mars' core does not generate this protective shield, and so the planet's surface conditions are hostile to life."
Mars Ping!.........................
This is a surprise, is it not? Had they not believed Mars no longer had a liquid core?
Yet another reason which explains why we are very likely alone in the known universe.
What keeps the core in a liquid state?
Yes...................
“While the core reveals Mars does not currently have a magnetic field, traces of magnetism in Mars’ crust reveal it may have at one time, according to Schmerr.”
Hmm, are they just talking about the local magnetic pockets on the surface? Or have they detected actual evidence that there was once a planetary magnetic field???
Because it seems to me that a solid core would be required to generate a magnetic field, and it doesn’t seem sensible that Mars could have once had a solid core that later on melted. Not unless it’s a fragment of a larger planet that previously existed or something like that.
Pressure?
I’d think it is Mars’ mass that keeps it liquid. The temperature/pressure at that depth is going to determine what state the matter is in, and the mass of the planet will determine that temperature and pressure.
Does a seismometer make a sound?
What if there is no one to hear it?
Radioactive isotopes, mostly.
Always check before eating!
Radioactivity. The radioactive particles don’t simply dissipate and instead cause more radioactivity. And all the radioactive particles combined cause heat. Earth is sort of a “dirty bomb.”
Of course, the planets started off crazy hot, and that heat gradually dissipated over billions of years, but without radioactivity, the Earth would’ve cooled enough to be solid long ago. And the more they cool, the less radioactive the radioactive isotopes become.
Eventually, the radioactive isotopes all degrade into non-radioactive isotopes and the Earth will cool; I don’t know if this is expected to happen before our Sun goes nova.
Ppor word choice. By radioactive particles, I did not mean the atoms of radioactive isotopes, but the subatomic particles generated by radioactivity.
No, it listens......................
we are very likely alone in the known universe.
—
Alone - yes in the in the known universe with thousands of trillions of galaxies, each with hundreds of billions of stars - there is no life but here.
Sounds so early Middle Ages and the debates among scholars about how the rest of the Universe revolves around the Earth.
or perhaps a moon of another planet like Saturn ...
Earth, like most humans living on it, is not as unique as we’d like to think.
God’s creation. We are it.
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