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Earth's Inner Core Is Solid, But Squishier Than Previously Thought (abc.net.au)
brindafella writes: Earthquakes are telling scientists more about the core of the Earth, specifically that it is squishier than previously thought (by about 2.5%.) Associate Professor Hrvoje Tkali & Thanh-Son Pham of the Australian National University have made sense of data collected by seismographs around the world to put new numbers on the density and pressure of the core. In Science magazine, they show that the pressure is 167.4 +/- 1.6 gigapascals (GPa) in Earth's center. For reference, standard atmospheric pressure is 101,325 pascals (Pa), so the center of the Earth is around 61 million times this pressure, but still 2.5% lower than expected.
For Americans: "101.325 pascals (Pa)"
...by Laura Petrie on "The Dick Van Dyke Show".
https://www.youtube.com/watch?...
15:50
I see even classic Slashdot is now pretty much unusable on dial up anymore.
This is not an area I know much about, but the numbers quoted seem screwy to me. How does 167.4 GPa (167,400,000,000 Pa) / 101,325 Pa (by my calculations 1,652,110) come out as 61,000,000?
No. 1 ATM is ~101,325 Pa, or about 14.7 psi. Your number would be 1000 ATM.
Browsing at +1 - no ACs, I ignore their posts. So refreshing!
> Earth's Inner Core Is Solid, But Squishier Than Previously Thought So following the logic, is should say: "Earth's Inner Core Now Is Thought To Be Solid, But Squishier Than Previously Thought."
I think the GP was saying 101.325 kPa, which is 101,325 Pa. I think they were using a comma for the decimal instead of the period used in the USA and other places. Notice the "(= 101325 Pa)" after "101,325 kPa".
What exactly is the SI unit of squishiness anyway?
Confucius say, "Find worm in apple - bad. Find half a worm - worse."
Even the trolls here suck now. Rob Malda went from what used to be a great site to talking about baseball and basketball. Someone, please take me back to 1999.
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Don't click that link.
Then I'm not sure why he wrote what he wrote? That's exactly what the summary stated.
Browsing at +1 - no ACs, I ignore their posts. So refreshing!
Or were you just trying to be funny?
Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
What does squishy mean? That the earths core is compressible or that it is less viscous than thought? The article seems to think compressible.
Sounds like scientists have thought of a way to keep their theory alive and this is not the first time they have used this "fudge factor" technique. Just to mention a few other "new" elements added to theories recently as fudge factor elements that keep theories alive:
Black Holes - Gravitational theory and measurements of the visible stellar systems don't result in the working model of what is known about galaxies.
Dark Matter - Gravitational theory and measurements of the visible universe don't result in the working model of what is known about systems of galaxies.
Dark Energy - Gravitational theory and measurements of the visible universe don't result in the working model of what is known about systems of galaxies.
And now: the center of the Earth is in a non-liquid type of compressible pseudo-liquid/gas - all because measurements of the "visible universe" don't result in the working model of what is known about the planet earth.
The emerging pattern here is that the scientific community are ever willing to invent ever more non-scientific explanations involving invisible, dark, obscure un-measurable and fantastic elements and continue with their precious theories.
I guess the question becomes: Who cares? All we need is an education system that churns out minds willing to accept the spam while they continue to muddle away with their coveted derivatives until the next correction is needed.
Young's modulus is the 'compressibility' that, in combination with density, determines the speed of (and the refraction and reflection of) P-type sound waves.
Just as you can see the extra sparkle of a diamond next to a piece of glass, the refraction of seismic waves allows one to determine the elasticity and density of the medium through which the wave passes. It's hard, though, to figure out a full interior structure and composition of the planet, and this just means a new evaluation of that Young's modulus for a bit of solid thousands of kilometers underfoot, at pressures and temperatures that don't allow easy laboratory experiments.
So, outside the laboratory, you just wait for random earthquakes to make a lot of not-ultrasound picture fragments seen by seismometers near the antipodal points.
'Scientists have thought' isn't what happened here; the job of theorists to imagine a composition with mechanical properties to fit the new Young's modulus value is the thinking part, which happens next. The reported best-fit Young's modulus value is not thought, but observation. Ranting about 'thoughts' is just spin; it sounds less ridiculous than ranting against observations.
The reason we should care about this work, is that most of the planet we're standing on is under pressures higher than any bit of matter we can get a close look at. So is most of the matter in the solar system.