molten

What drives the rumbling vibrations, called tremor, that occur when molten rock or gases travel upward through underground channels?

The discovery focuses on rare natural glass called tektites, which form when a meteorite hits Earth with enough force to melt the surface and fling molten material vast distances.

As the molten iron and nickel slowly cool, they form swirling convection currents in the outer core.

Scientists have long believed that the early moon was once completely molten, forming a global "magma ocean."

It remains to be seen whether these new start-ups will make a big, molten splash in the steel industry any time soon.