You are watching: Which of the terrestrial worlds has the strongest magnetic field?
See more: If A Company Uses A Special Payroll Bank Account, Straighterline Acc1 Quiz 4
Which of the four terrestrial planets has the strongest magnetic area, Mars, Mercury, Venus, or Earth?
The Planet, by much.
The 4 huge planets have actually rather strong magnetic areas. Amongst the terrestrial planets, only the Earth has actually a moderately solid magnetic area, however weaker than those of the giant planets. Mercury, prefer the Earth, has a self-sustained dipole magnetic field, yet much weaker than that of the Earth. The Moon, and probably Mars, show up to have had actually prehistoric planetary dynamos, yet not anyeven more. Finally, Venus also does not have actually a self-continual dipole magnetic area.
One prior explacountry for why the Moon and also Mars execute not have actually self-continual dipole magnetic fields has actually fallen by the wayside. It was lengthy posited that the cores of the Moon and also Mars have long considering that frozen. This is not the instance. Analyses of the gravity fields of the Moon and also Mars have displayed that those two objects have partially molten cores consisting of iron and also other facets, just choose the Earth.
It shows up that 3 essential ingredients are needed for a terrestrial earth to have actually a far-reaching magnetic field:A molten or partly molten core consisting of iron, nickel, and also various other elements. All 4 terrestrial planets and the Moon pass this criterion.A sufficiently high rotation price. What that sufficiently high is topic to dispute. One rotation per sideactual day is obviously sufficiently high. Mars has actually a very similar rotation rate however does not have actually a self-continual dynamo.A sufficiently high heat flux across the core-mantle boundary. This is the one factor that distinguishes the Earth from the other four terrestrial objects. Mercury, the Moon, and Mars have static lid tectonics: their surdeals with are frozen. Venus shows up to have alternated between static lid tectonics (which is what it has actually now) and excessive volcanic tectonics (the a lot of reliable way to cool a planet).The Earth is the only among those 5 objects to have actually plate tectonics. While not as efficient as excessive volcanism via regard to cooling a world, it apparently is good enough to preserve the warmth flux throughout the core-mantle boundary that is necessary to preserve a self-sustaining dynamo.