Alpha Centauri

Alpha Centauri is a binary star system in the Sol Sector of the Orion Arm, lying exactly 4.37 light-years from the sector capital, and a very important political center in the Milky Way, Earth.

Its individual components are A. Centauri A, a yellow dwarf and A. Centauri B, an orange dwarf. As obvious, A is bigger than B because its a yellow dwarf star. The yellow dwarf is over 1.7 million km (730,000 miles) in diameter and has 1.1 times the mass of an average star. Both stars orbit around a common center of gravity. Over this 80 year orbital period, the stars orbit either very far or very close to eachother.

The star Proxima Centauri, which lies 0.17 light-years closer to Sol than the A. Centauri system, is not gravitationally associated with the pair. Seven planets orbit these stars.