Hot cores...planets.

[princemyheart]

So... the Earth is hot in the centre due to the pressure?
Do all the other planets and large enough bodies have a hot core? :shifty:

[pzkpfw]

Most of the heat is from radioactivity.

http://www.physorg.com/news62952904.html

[WayneFrancis]

As I understand it Mercury is solid all the way through, Venus has a molten core but because of the slow rotation it does not produce much of a magnetic field. Mars is solid or very near solid. Jupiter might have a rocky type core but I believe that it would be VERY hot. Even if it does it has a hydrogen plasma core which is also very hot.
Saturn might have a rocky core but is very unlikely to be very hot. The same goes for the 2 ice giants and Pluto is definitely cold.

[tusenfem]

As I understand it Mercury is solid all the way through,


Nope, the fact that Mercury has an internal magnetic field shows that it has a fluid iron core in which the dynamo works.



Venus has a molten core but because of the slow rotation it does not produce much of a magnetic field.


Not only the slow rotation, the fact that the outer surface of Venus is so hot, might stymy the convection in the fluid core (no heat transport possible) and thus no dynamo is set up.

[aurora]

Some moons have molten interior (rock or water) due primarily to gravitational interactions.

Europa, Io, Enceledus, Triton to name the most obvious.

[Ilya]

Saturn might have a rocky core but is very unlikely to be very hot. The same goes for the 2 ice giants

What makes you think so? Like Jupiter, Saturn and Neptune both emit more heat than they receive from the Sun, which implies they are very hot inside.

[WayneFrancis]

Nope, the fact that Mercury has an internal magnetic field shows that it has a fluid iron core in which the dynamo works.



Not only the slow rotation, the fact that the outer surface of Venus is so hot, might stymy the convection in the fluid core (no heat transport possible) and thus no dynamo is set up.

thanks for correcting me.

[WayneFrancis]

What makes you think so? Like Jupiter, Saturn and Neptune both emit more heat than they receive from the Sun, which implies they are very hot inside.

I stand corrected, just found an article that the core of Saturn is estimated to be about 11,700 °C. which is much hotter then our core.