What is the bright light in the middle of the Milky Way galaxy?

Well, isn't that a lovely question. That bright light in the middle of the Milky Way galaxy is our magnificent supermassive black hole, called Sagittarius A*! It's like the heart of our galaxy, energy radiating out in beauty all around. Keep exploring the universe with that curious mind of yours, and let the wonder of it all fill your heart with joy.