How has Earth's core stayed as hot as the sun's surface for billions of years?

[Admin]

How has Earth's core stayed as hot as the sun's surface for billions of years? : Read more

 

[orsobubu]

these are all stupid and unsupported theories; no physical mechanism to trap all that heat during 5 billion years, no physical mechanism to explain the starting incredibly high temperature the core should have had due to the merger of planetesimals, no physical mechanism to explain the high temperature of the original dust disk around the sun, no physical mechanism to explain an hypotetical gravitational collapse of the new condensed planet earth, no physical mechanism to explain the amount of energy producing the heat by radioactivity decay, no data to show the huge loss of temperature from the core during past earth's life, no data to show the necessary production of many types of radioactive isotopes as a result of the fission process, no physical mechanism to explain why the same heat creation process is not ongoing in all the other solar system solid bodies

 

[Classical Motion]

The earth remains a hard nut to crack. Our deepest attempts are only small pricks. We found it saturated with super-heated high pressure water. This water should be highly conductive. Our crust might have an electrical character to it. There might even be electrical layers in the earth, like there is above the earth.

Some studies show the gravity reaches a maximum at a shell, with a decrease in gravity inside that shell in the center. The gravity gradient under the shell might be opposite the gravity gradient above that shell. A pulling up force at the center. Wouldn't that be wild.

This water would easily flash at the surface and give a huge source of power. But it would not be free. Like other geo-hydro sites, there are contaminates in the steam and water. High maintenance and replacement repair.

 

[Jan Steinman]

these are all stupid and unsupported theories…

Uhm… would you care to present your credentials, and documentation for your beliefs?

Didn't think so!

 

[rod]

"Where does all that heat come from? It is not from the sun. While it warms us and all the plants and animals on Earth's surface, sunlight can't penetrate through miles of the planet’s interior. Instead, there are two sources. One is the heat that Earth inherited during its formation 4.5 billion years ago. The Earth was made from the solar nebula (opens in new tab), a gigantic gaseous cloud, amid endless collisions and mergers between bits of rock and debris called planetesimals. This process took tens of millions of years. An enormous amount of heat was produced during those collisions, enough to melt the whole Earth. Although some of that heat was lost in space, the rest of it was locked away inside the Earth, where much of it remains even today. The other heat source: the decay of radioactive isotopes, distributed everywhere in the Earth."

This is view is interesting in the article. The giant impact for the origin of our Moon does not feature a fully formed Earth as we see today but a proto-earth and a proto-moon that evolves after the giant impact, thus both earth and moon must continue to grow in size and mass until what we see today. Explaining how Earth evolved in the solar nebula and Venus evolved so very differently, from the same nebula and postulated protoplanetary disc, remains very challenging. This model interpretation presented explaining the heat today, could have some holes in it.

NASA scientist explains why Venus is Earth's 'evil twin' (video)

Scientists and engineers from NASA and the European Space Agency want to know a whole lot more about why Venus resembles Earth in so many ways, and yet is so strikingly different. NASA scientist explains why Venus is Earth's 'evil twin' (video) : Read more

forums.space.com

 

[WisdomLost]

I've heard the isotope/radiation theory, and thought it was an interesting guess. Personally, I always thought the core was active due to the tidal effect of our relatively large moon.

With the constant churning of the moon's pull, the mantle stays relatively fluid, and the core oscillates within that "fluid". Resulting friction would produce a lot of heat.

I don't know a lot about the inner workings of Mars, but also assumed the lack of a large moon accounted for the dead core (though recent seismic readings suggest it's not as dead as we thought).

Venus is just plain hot. Solar accounts for the extreme temperature at the surface, but I don't know if the core is active. Same for Mercury. There are no other "rock" planets in our solar system to compare to, so my guess probably couldn't be "proven" by comparison. However, we do see evidence of active cores on moons orbiting large gas giants.

 

[rod]

Perhaps there is heat/cooling problems in the solar system, whether Earth or some small moons or other planets. I have read over the years different reports that indicate heat/cooling issues come up when showing how something remains hot over a 4.5 Gyr solar system model.

 

[theglassisempty]

these are all stupid and unsupported theories; no physical mechanism to trap all that heat during 5 billion years, no physical mechanism to explain the starting incredibly high temperature the core should have had due to the merger of planetesimals, no physical mechanism to explain the high temperature of the original dust disk around the sun, no physical mechanism to explain an hypotetical gravitational collapse of the new condensed planet earth, no physical mechanism to explain the amount of energy producing the heat by radioactivity decay, no data to show the huge loss of temperature from the core during past earth's life, no data to show the necessary production of many types of radioactive isotopes as a result of the fission process, no physical mechanism to explain why the same heat creation process is not ongoing in all the other solar system solid bodies

It does take that long to cool off, do the math. And, there is residual radioactivity keeping up the temperature. Your ramblings are the only unsupported "theories" around here . . . . .

 

[rod]

Some interesting comments here in various posts. Who, what, when, where, how, and why are good investigative questions to ask.

For example, what was the original core temperature of Earth when it was a proto-earth before the giant impact with Theia - creating the Moon? The proto-earth is not the same size or mass as we live on today but smaller in size and mass. Initial conditions must be defined, heat loss rates, heat sources for adding heat, etc., accretion growth rates, etc.

 

[rod]

https://www.scientificamerican.com/article/why-is-the-earths-core-so/, Why is the earth's core so hot? And how do scientists measure its temperature?

There are some model answers in the link but IMO, still not very good and lacking details.

 

[ScientistMan]

Given the difference in half life between U235 and U238, it is common knowledge that the natural uranium enrichment was much higher early in the earth's life. Just like there were natural reactors in 'operation' at that time (like Oklo in Gabon), perhaps the entire core (pardon the pun) was one massive yet self regulated nuclear fission reactor producing an insane amount of heat over that time. Is there evidence to suggest any significant quantities of uranium in the core?