The surface temperature of the Sun is closest to the temperature at the boundary between Earth's mantle and core. Here's why:
1. The Sun: The Sun has a surface temperature of about 5,500 degrees Celsius (9,932 degrees Fahrenheit). This temperature is relatively close to the estimated boundary temperature between Earth's mantle and core, which is around 5,000 degrees Celsius (9,032 degrees Fahrenheit).
2. Sirius, Rigel, and Betelgeuse: Sirius, Rigel, and Betelgeuse are all stars with varying surface temperatures that are significantly different from the temperature at the boundary between Earth's mantle and core. They are much hotter compared to the Sun and the estimated temperature at the mantle-core boundary.
Therefore, the Sun's surface temperature is the closest to the temperature at the boundary between Earth's mantle and core among the stars listed in the question.
