The Sun's atmosphere, called the solar corona, extends millions of kilometers into space. It is the outermost layer of the Sun and is best seen during a total solar eclipse.

The corona is composed of extremely hot, rarefied gas and is the source of the solar wind, a stream of charged particles that flows continuously outward from the Sun.

The corona is divided into two regions:

- The lower corona, which is denser and cooler, and

- The outer corona, which is less dense and hotter.

The corona is heated to temperatures of over 1 million degrees Celsius, making it much hotter than the Sun's surface.

The solar atmosphere is constantly in motion, with enormous magnetic storms and solar flares occurring regularly. These events can disrupt radio communications and power grids on Earth and pose a risk to astronauts in space.