Re: Trying to make sense of some recent Mars News
The martian core is a little over half the diameter of Earth's. So the martian core's average angular-velocity is corespondingly smaller than Earth's
core velocity.
That means? That even a long time ago the martian core wasn't spinning fast enough to generate a strong magnetic field to begin with; and due to gradual cooling of the martian core, the weak martian magnetic-field grew weaker and weaker until it died.
That's the simple explanation.
Nick, or Dr. Blackwell, can give you
a more concise, computational explanation than me.
cheers.
Jacob