Astronomy Picture of the Day

Explanation: The Sleep ing Beauty galaxy may appear peaceful at first sight but it is actually tossing and turning. In an unexpected twist, recent observations have shown that the center of this photogenic galaxy is rotating in the opposite direction than the outer regions! Stranger still - there is a middle region where the stars rotate in the opposite direction from the surrounding dust and gas. The fascinating internal motions of M64, also cataloged as NGC 4826, are thought to be the result of a collision between a small galaxy and a large galaxy where the resultant mix has not yet settled down.

睡美人星系（又稱NGC 4826）乍看之下似乎很平靜，但實際上正在經歷劇烈的變動。 它最近更出現意外的轉折：最近的觀測顯示，這個很上相的星系之中心與外部區域的旋轉方向竟然相反！ 而更加奇特的是，中心區恆星的旋轉方向居然也與周圍的塵埃和氣體相反。 這個內部運動異常有趣的星系，咸信是小星系和大星系發生互撞，而所造成的合併天體目前尚未穩定下來。