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Earth's core far hotter than thought

bbc.co.uk

1–10 of 28 posts

Re: Earth's core far hotter than thought

#3
This article is fascinating but as someone who doesn't know much about this discipline, I'm hoping for someone to clarify my confusion:

In the article, it states that our core has temperatures comprable to that of the sun. However, the sun is 93 million miles away while our core seems to only be approximately 4000 miles deep. Shouldn't the Earth be hotter than or are there just so many layers that the heat decreases at such a fast rate as it approaches the surface?

Re: Earth's core far hotter than thought

#5

This article is fascinating but as someone who doesn't know much about this discipline, I'm hoping for someone to clarify my confusion: In the article, it states that our core has temperatures comprable to that of the sun. However, the sun is 93 million miles away while our core seems to only be approximately 4000 miles deep. Shouldn't the Earth be hotter than or are there just so many layers that the heat decreases…

They're comparing the heat of Earth's core to the surface of the sun, not the core of the sun.

Re: Earth's core far hotter than thought

#6

This article is fascinating but as someone who doesn't know much about this discipline, I'm hoping for someone to clarify my confusion: In the article, it states that our core has temperatures comprable to that of the sun. However, the sun is 93 million miles away while our core seems to only be approximately 4000 miles deep. Shouldn't the Earth be hotter than or are there just so many layers that the heat decreases…

The sun heats the earth surface through radiative heating, while the core is well insulated by the mantle and crust. Although they may have similar temperatures, the power output of the sun is certainly larger.

Re: Earth's core far hotter than thought

#7
post #4

It's a shame there's no good way to harness that.

Although it's admittedly difficult when the higher temperatures are hundreds or thousands of kilometers away, geothermal power plants do in fact harness that.

If I am not mistaken Iceland uses geothermal to a large extent and is very successful in doing so.

Re: Earth's core far hotter than thought

#8

It's a shame there's no good way to harness that.

It's important to note the fact that the heat in the core does not exist in isolation of other fields. The Earth is a dynamo system, and the energy in the core is connected to the planet's magnetic field, the energy bound up in its orbit around the sun, and its gravitational field.

Re: Earth's core far hotter than thought

#9

This article is fascinating but as someone who doesn't know much about this discipline, I'm hoping for someone to clarify my confusion: In the article, it states that our core has temperatures comprable to that of the sun. However, the sun is 93 million miles away while our core seems to only be approximately 4000 miles deep. Shouldn't the Earth be hotter than or are there just so many layers that the heat decreases…

I'm afraid there are many things wrong with your model of how heat works. However a simple factor is that the surface of the sun is ~10000 times larger than the surface of the earth.

Re: Earth's core far hotter than thought

#10
post #6

This article is fascinating but as someone who doesn't know much about this discipline, I'm hoping for someone to clarify my confusion: In the article, it states that our core has temperatures comprable to that of the sun. However, the sun is 93 million miles away while our core seems to only be approximately 4000 miles deep. Shouldn't the Earth be hotter than or are there just so many layers that the heat decreases…

The sun heats the earth surface through radiative heating, while the core is well insulated by the mantle and crust. Although they may have similar temperatures, the power output of the sun is certainly larger.

To provide some further context to ovis' (correct) statements, none of our 'heat', or other energy from the sun comes in the form of conduction. It comes in the form of radiation (light, et al) which the sun has in huge, massive, ginormous quantities. In pop culture, we often talk about the heat of the sun as if it's a direct indicator for the amount of power therein, and the amount of power output. But while it's quite hot, its also quite busy showering us with other forms of energy.
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