Question

The sun is a star. How do we say that?

Answer 1

A star is called a "sun" if it is the center of a planetary system. A large number of planets have been found that orbit other stars, thus making these stars officially "suns." Chances are that a large percentage of the stars in the galaxy also have planets orbiting them, which would make them suns as well.

Answer 2

here you go....

The Sun is by far the largest object in the solar system. It contains more than 99.8% of the total mass of the Solar System (Jupiter contains most of the rest). It is often said that the Sun is an "ordinary" star. ... This changes slowly over time as the Sun converts hydrogen to helium in its core.