Hi all this is my first post. I'm not formally educated in physics concepts but find so much about it very interesting. I registered to ask if this is plausible: It appears we attribute our electromagnetic field on Earth to it's behavior deep inside the planet. There is supposedly a solid core in the middle surrounded by what might be molten metal that circulates in some regular way which creates the field. Right? On Mars resides the largest volcano in the solar system in Olympus Mons. Is it possible that much of Mars' required ingredient for an electromagnetic field (molten metal) was lost through this volcano and therefore couldn't maintain it's electromagnetic field?