Io's Ocean of Magma ?

[fosborn]

In a new article concernig the discovery of Io's magma, they speak of gravitational stresses heating up the interior. I have also read else where that the flux tube between Io and Jupiter conducts 2 trillion watts of electrical power. Is this a factor in heating up Io too?

[cjameshuff]

In a new article concernig the discovery of Io's magma, they speak of gravitational stresses heating up the interior. I have also read else where that the flux tube between Io and Jupiter conducts 2 trillion watts of electrical power. Is this a factor in heating up Io too?

http://www.wolframalpha.com/input/?i...%5E%281%2F4%29

That amount of power would be radiated by an object of Io's surface area and an emissivity of 1 at a temperature of about 30 K. Io's mean surface temperature is 110 K, which would make for 350 TW of radiation, but it's got considerable variation in surface temperature that make it radiate more effectively (remember that radiated power scales with temperature^4). It's receiving some 470 TW of sunlight, which it must radiate along with the heat gained via other means:
http://www.wolframalpha.com/input/?i...1%2F5.5%29%5E2

Where the energy is deposited matters too. Tidal flexing dumps energy deep into the interior, where there's a thick insulating blanket of rock between it and the surface. Charged particles might make a difference if they were similar, but they probably dump most of their energy into the near-surface layers along with the sunlight, very little being deposited deep inside Io.

[tusenfem]

The currents through the Io flux tube do not go through the moon proper, they are closed through the ionosphere and thus do not heat up the moon.

[fosborn]

Thanks for the Wolfram links and the explanations.

[fosborn]

Thanks for the understandable explanations and the Wolfram links!