Why does only the Earth have plate tectonics?

Without plate tectonics our planet would be a very different place. The constant recycling of the Earth’s crust provides us with a stable climate, mineral and oil deposits and oceans with a life-sustaining balance of chemicals. It even gives evolution a kick every few hundred million years. read more

So there is a pattern there - planets or moons with evidence of resting liquid on the surface have evidence for tectonic activity. Those that don’t have any evidence for liquid also do not have evidence for plate tectonics (even in a different form to what we understand here on Earth). read more

The existence of plate tectonics on other planets and moons depends on the composition of the mantle and the lithosphere and on their mass. As a rule of thumb, larger celestial bodies should be expected to have or at least have had plate tectonic activity as long as the mantle is warm enough. read more

Models have shown that for plate tectonics to get going a planet has to be just the right size: too small and its lithosphere – the solid part of the crust and upper mantle – will be too thick. read more

The plates on the surface essentially float on mantel, which is why, in laments terms, Earth has plate tectonics. The other rocky planets once had plate tectonics much like Earth, but as Mars is much smaller and more importantly less dense than Earth. read more

Plate tectonics on earth may have been triggered by the same massive impact that created the moon, which destroyed/melted/blew into space earth’s original crust which may have been too thick for plate tectonics to get started, and allowed the formation of the current thinner crust it has today, which can support plate tectonics. read more