Seen in Print

[Roy]

Where is the EXIT TO THE OTHER SIDE OF THE WORLD located?

If you dig straight down from anywhere in the 48 contiguous United States, you'll come out in the Indian Ocean.

Better be able to swim if you try this.

While true, I don't know the location of the sign so the exit point is equally unknown

Aren't you likely to bump into a lot of molten iron, where ever you start?

[MurphOnMillerAve]

Where is the EXIT TO THE OTHER SIDE OF THE WORLD located?

If you dig straight down from anywhere in the 48 contiguous United States, you'll come out in the Indian Ocean.

Better be able to swim if you try this.

While true, I don't know the location of the sign so the exit point is equally unknown

Aren't you likely to bump into a lot of molten iron, where ever you start?

You are totally right, Roy. The Inner Core and Outer Core are molten. And how do we know that? Any doubters can simply walk up to any of the thousands of active volcanoes worldwide, but they shouldn't stand too close. Magma from the Mantle has been pushed upward and is ready to say Hi!

[Rufus T. Firefly]

Where is the EXIT TO THE OTHER SIDE OF THE WORLD located?

If you dig straight down from anywhere in the 48 contiguous United States, you'll come out in the Indian Ocean.

Better be able to swim if you try this.

While true, I don't know the location of the sign so the exit point is equally unknown

Aren't you likely to bump into a lot of molten iron, where ever you start?

And the Devil.

[Rufus T. Firefly]

FYI..........

[webenda]

I don't trust that list Rufus, too many of the entries are fanciful and never found outside of word lists.

[Rufus T. Firefly]

I don't trust that list Rufus, too many of the entries are fanciful and never found outside of word lists.

The list does not require nor request your trust. You can either make use of it or not. However, it may still be useful.

[Tom Dempsey]

Why would anyone require an entire harem of sexbots?

[Rufus T. Firefly]

Why would anyone require an entire harem of sexbots?

Why not?

Why do some folks fill closets and basements with trains that they never take out of the box?

[Tom Dempsey]

Why do some folks fill closets and basements with trains that they never take out of the box?

Well, that's a whorse of a different color there Rufus, you can play with all your trains at the same time, but you can only play with one sexbot at a time.

[webenda]

Where is the EXIT TO THE OTHER SIDE OF THE WORLD located?

If you dig straight down from anywhere in the 48 contiguous United States, you'll come out in the Indian Ocean.

Better be able to swim if you try this.

While true, I don't know the location of the sign so the exit point is equally unknown

Aren't you likely to bump into a lot of molten iron, where ever you start?

You are totally right, Roy. The Inner Core and Outer Core are molten. And how do we know that? Any doubters can simply walk up to any of the thousands of active volcanoes worldwide, but they shouldn't stand too close. Magma from the Mantle has been pushed upward and is ready to say Hi!

There are plenty of earthquakes every day, in fact, the numbers have been increasing over the last few decades. Seismic stations dotted all over the Earth record the arrival of the tremors from the earthquakes. A tremendous amount of data has been collected. Vibrations from an earthquake are categorized as L (L stands for Love waves after a guy named Augustus Edward Hough Love), P (P stands for pressure) and S (S stands for shear) waves. They travel through the Earth in different ways and at different speeds.

From examining the way these waves travel through the Earth science has concluded that the Earth's core is solid. The transition between the inner core and mantle is liquid.

The S waves tell us that there is liquid below the mantle because S waves cannot travel through a liquid and there is a big shadow of no S waves detected on the opposite side of the Earth from an earthquake. The P-waves tell us that the Earth's core is solid by speeding up but not as fast as they would in pure iron. So, it is something else, what we do not know... yet.

I vote for Mercury. The speed of sound is 1,450 m/s in mercury and 5,130 m/s in iron. The speed of P-waves would be slower through mercury also. The Earth has a much higher density than if it were rocks all the way through. Iron was long thought to be the material in the center because Iron has the right density to balance the total mass of the Earth equation. But, it can't be pure iron. One problem with Iron as the answer is how slow P-waves travel through the core of the Earth. Another problem is, even in the molten state, iron does not travel through rocks, it just puddles, so how did it find its way to the center? Mercury, on the other hand, does flow through rock. Mercury spills have contaminated underground water supplies. It also dissolves iron in rock. A perfect carrier to get iron (and gold) to the center of the Earth. Sound would travel slower through a mercury/iron amalgam.

Magma from volcanoes has nothing to do with the core of the Earth. The outer core of the Earth starts at about 3,000 km below our feet. The lava that spews from volcanoes first melts just a few hundred kilometers down. The source pools of volcano magma are just tens of kilometers down. Accurately measured volcanic fissures/feeder-dykes in El Hierro (Canary Islands) indicate a source depth of 11–15 km, which coincides with the main cloud of earthquake foci surrounding the magma chamber associated with the 2011–2012 eruption of El Hierro.

References:
https://www.energy.cam.ac.uk/directory/satr@cam.ac.uk
aesl.ces.uga.edu/publications/watercirc/Mercury.pdf

I feel sorry for teachers trying to teach the mysteries of the inner workings of Earth using government supplied teaching tools. In this case (below) the tool is supplied by © Royal Society of Chemistry 2018. Registered charity number 207890.

Students complete written answers to the worksheet Structure of the Earth: the story of the waves.

Q 5. Summarise the properties of the different layers labelled 1-4 in the diagram below. The first one has been done for you. (On this diagram the crust is shown thicker than it really is, so that it can be seen.)

(1) ‘P- and S-waves pass through the crust, so it is solid.’
(2) Student answers
(3) Student answers
(4) Student answers

My answers:

(1) ‘P- and S-waves pass through the crust, so it is solid.’
(2) P- and S-waves travel through the mantle, so it is solid.
(3) S-waves cannot travel through the outer core so it is liquid.
S-waves travel slower through outer core, so it is liquid.
S-waves do not travel as fast through the outer liquid outer core as they would through liquid iron, so the outer core is not pure iron.
(4) S-waves travel faster through inner core, so it is solid but not as fast as through solid iron, so the inner core is not pure iron.

Answers to questions: (for teachers grading students)

Q 5.
(2) P-waves travel faster through mantle than S-waves. Mantle is solid
(1) S-waves cannot travel through outer core so it is liquid
(3) P-and S-waves travel through inner core so it is solid.

How sad in that? The answers are not numbered correctly and 3 is wrong even if it was numbered correctly. No wonder students hate science.

[Roy]

Wayne, would mercury in the Earth's core be able to account for the Earth's magnetic field?

[Roy]

...you can play with all your trains at the same time...

Seems unlikely.

...but you can only play with one sexbot at a time.

Sounds arbitrary.

[Rufus T. Firefly]

Why do some folks fill closets and basements with trains that they never take out of the box?

Well, that's a whorse of a different color there Rufus, you can play with all your trains at the same time, but you can only play with one sexbot at a time.

In the case of the former, no, I can't.

In the case of the latter, I know that's not true........and I want more..........

https://www.youtube.com/watch?v=5W6gjAAHvo0

[MurphOnMillerAve]

Wayne, would mercury in the Earth's core be able to account for the Earth's magnetic field?

I think it's long been taught that iron is present there.

[healey36]