The Sun formed approximately 4.6 billion years ago from a vast cloud of gas and dust in a region of our galaxy, the Milky Way.
Gravity gradually drew material toward the center of the cloud, creating a dense and hot protostar. As this protostar collapsed, the pressure and temperature at its core increased significantly.
Eventually, conditions reached a point where nuclear fusion of hydrogen began in its core, releasing an immense amount of energy.
This process, known as thermonuclear fusion, led to the formation of the Sun, a yellow dwarf star that has been shining in our solar system ever since.
