NASA 4.25 light years away Nearest Star Proxima Centauri Alpha Centauri A and B Alpha Centauri 4.25 light years away 半人馬座阿爾法星 268,770 AU 4.25 light years away very far away next nearest star red dwarf بروكسيما سينتوري one of three stars would still have to travel for over 73,000 years Proxima Centauri Alpha Centauri A and B Alpha Centauri A and B 4.22 light-years Proxima Centauri The Nearest Star | NASA Proxima Centauri Alpha Centauri A and B Proxima Centauri