If Olympus Mons definitively the tallest / largest mountain in our solar system, how do we know the gas giants don’t have similar or larger mountains underneath their thick atmospheres?

Question

If Olympus Mons definitively the tallest / largest mountain in our solar system, how do we know the gas giants don’t have similar or larger mountains underneath their thick atmospheres?

In: 583

Answer 1

The jovian planets are “gas giants” because they’re made of gasses. They’re not terrestrial, as in they don’t have rock formations, etc like you find on the terrestrial planets.

Any solid surface they have is likely solid hydrogen at the very core of the planet, but mostly they’re made of gaseous hydrogen and helium just like a star, but not enough of it to cause fusion, which is why they’re often referred to as “failed stars”. It’s unlikely they have anything resembling a volcano like you’d find on a terrestrial planet.