The Sun's temperature varies greatly depending on the layer:

• Core: The hottest part of the Sun, reaching about 15 million degrees Celsius (27 million degrees Fahrenheit). This extreme heat is due to nuclear fusion, where hydrogen atoms fuse into helium, releasing vast amounts of energy

• Radiative Zone: Surrounding the core, temperatures range from around 7 million degrees Celsius near the core to about 2 million degrees Celsius farther out

• Convective Zone: Temperatures drop from about 2 million degrees Celsius down to approximately 5,800 degrees Celsius as heat moves toward the surface

• Photosphere (Surface): The visible surface of the Sun is much cooler at about 5,500 to 5,800 degrees Celsius (around 10,000 degrees Fahrenheit). This is the layer that emits the sunlight we see

• Sunspots: Cooler regions on the photosphere, with temperatures between roughly 3,000 to 4,500 degrees Celsius (5,400 to 8,100 degrees Fahrenheit)

• Chromosphere: Above the photosphere, temperatures rise again to about 6,000 to 8,000 degrees Kelvin (around 11,000 to 14,000 degrees Fahrenheit)

• Corona (Outer Atmosphere): Surprisingly, the outermost layer is extremely hot, with temperatures ranging from about 1 million to 3.6 million degrees Fahrenheit (about 1 to 2 million degrees Celsius), and in some regions even reaching up to 10 million degrees Celsius. This is much hotter than the surface, and the reason for this intense heating remains a subject of scientific investigation

In summary, the Sun's temperature is highest at its core (~15 million °C), drops to about 5,500–5,800 °C at the surface, and then rises dramatically again in the corona to millions of degrees Celsius