sagittarius a star is the black hole in the middle of the milky way galaxy - 天鵝座 星座區域 幅插畫檔、美工圖案、卡通及圖標
artist's concept of cygnus x-1, a luminous x-ray source in the constellation cygnus. - 天鵝座 星座區域 幅插畫檔、美工圖案、卡通及圖標