A Class G star is the third-dimmest type of main sequence star besides brown dwarfs. They are typically colored yellow or yellow-white. They made up roughly 8% of all main-sequence stars.

A typical Class G star has a mass of 0.9 (0.8 to 1.04) solar masses, a radius of 1.05 (0.96 to 1.15) solar radii, a luminosity of 1 (0.6 to 1.5) solar luminosity, a surface temperature of 5,600 K (5,200 K to 6,000 K), and a lifespan of 10 to 15 billion years.
Sun Class G

The Sun, a class G2V star

Their habitable zones range from ~0.6 to 1 AU, and their long lifespans and relatively high brightness means they are very good candidates for life-bearing planets. Earth's sun is a class G star, actually, as are many stars with known extrasolar planets.
Stellar Classes
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