A dying star that explodes into millions of lights is called a supernova.

Here's why:

* Supernova: This is the massive explosion of a star at the end of its life. It releases an enormous amount of energy and light, making it appear incredibly bright for a short period. The explosion scatters the star's material into space, creating a nebula.

* Millions of Lights: The intense brightness of a supernova is due to the massive energy release, making it appear as if millions of lights are being turned on simultaneously.

While it's not technically accurate to call a supernova "millions of lights," it's a poetic way to describe the awe-inspiring spectacle of a star's death.