The Sun is classified as a G-type main-sequence star, commonly referred to as a G dwarf star. Specifically, its spectral class is G2V.
This classification is based on the Sun’s surface temperature, which is about 5,500 degrees Celsius (9,932 degrees Fahrenheit). The ‘G’ signifies that it has a yellowish hue with a spectrum that shows strong absorption lines from ionized metals, particularly calcium and iron. The ‘2’ in G2 indicates the Sun is in the middle of the G class, while ‘V’ signifies that it is a main-sequence star, meaning it is in a stable phase of hydrogen burning.
Understanding the spectral class of the Sun helps astronomers categorize it among other stars and provides insights into its size, composition, and temperature, which are crucial for understanding its lifecycle and impact on the solar system.