The star Alpha Centauri A and the star Alpha Centauri B form the double star system Alpha Centauri, which can be seen in the constellation Centaurus. But Alpha Centauri A is the larger of the two solar stars and the primary star of the solar system.
Facts about Alpha Centauri A
Alpha Centauri A has an apparent magnitude of -0.01 mag and is therefore the fourth brightest star in the sky. It is a yellow bright star, which is classified as a yellow dwarf like the sun and belongs to the spectral type G2 V. Alpha Centauri A is also seen as a twin of the Sun, because it is of the same spectral type as the Sun and has similar dimensions. In addition, it is 23% larger than the Sun, although its mass is only 10% larger than the Sun. Its chemical composition is also very similar to the sun, but its proportion of heavy elements is almost 70% higher. Scientists often refer to it as Pandora's Sun. The surface temperature of Alpha Centauri A is 5800 K and it has 1.22 times the diameter of the sun. Thus it is larger than Alpha Centauri B.