Galactic center early-type stars catalog

It is still unclear whether the Sagittarius spiral arm is a major spiral arm in the Galaxy or whether it just outlines a region of enhanced star formation because of the local...目前仍无法明确，人马座旋臂(Sagittarius spiral arm)究竟是银河系的主要旋臂之一，还是仅勾勒出一个因局部……而出现恒星形成增强现象的区域。