What realm provided the sparks that became the stars?

What realm provided the sparks that became the stars? Muspelheim provided them.

In the Norse creation story, Ginnungagap was the primordial void between the icy realm of Niflheim and the fiery realm of Muspelheim. Heat, sparks, and molten flecks flew from Muspelheim into the void. When they met the ice and rime, the melting produced the conditions from which Ymir and other early beings arose.

The sparks were later assigned a cosmic role: they became the Sun, Moon, and stars. This makes Muspelheim more than simply a land of fire; its energy is part of the mythic formation of the visible universe. Muspelheim is also home to fire giants and is associated with the giant Surtr.

The realm returns at Ragnarök, when Surtr and the forces of Muspell advance against the gods and the world is consumed by fire. A common mix-up is choosing Niflheim because ice and frost dominate the opening scene, but the sparks themselves come from the fiery southern region.