Mercury found to be tectonically active

Noob question. Aren&#x27;t the moons of Jupiter and Saturn also tectonically active? With the immense solar pull, Mercury would have some heavy sheer forces causing plates to move.<p>I am sure I am missing something. Please enlighten me.

If Mercury is tectonically active, that spells trouble for Kim Stanley Robinson&#x27;s sci-fi city on rails, Terminator, continuously rolling away from the dawn, powered by the thermal expansion from direct sunlight.<p>If you need the rails running around the equator to remain straight in order to keep moving at a constant rate, all your railroad ties now have to compensate for the shifting plates.<p>At least that story accounted for Mercury not being tidally locked to the Sun.

It has highly eccentric orbit, tidal forces must be enormous.

How much incidence has its proximity with the Sun? Can the Sun affect it in a similar way Jupiter or Saturn affects its moons?

Pretty surprising for a tidally locked and that small of a body.

so if planets can shrink, can they grow?

Ridiculously, I never twigged until now that the planet and the element shared a name despite being aware of both, forever.