2025年5月7日
Galaxy Wars: M81 versus M82
Image Credit & Copyright: Collaborative Astrophotography Team (CAT)
Explanation: In the upper left corner, surrounded by blue arms and dotted with red nebulas, is spiral galaxy M81. In the lower right corner, marked by a light central line and surrounded by red glowing gas, is irregular galaxy M82. This stunning vista shows these two mammoth galaxies locked in gravitational combat, as they have been for the past billion years. The gravity from each galaxy dramatically affects the other during each hundred-million-year pass. Last go-round, M82‘s gravity likely raised density waves rippling around M81, resulting in the richness of M81‘s spiral arms. But M81 left M82 with violent star forming regions and colliding gas clouds so energetic the galaxy glows in X-rays. This big battle is seen from Earth through the faint glow of an Integrated Flux Nebula, a little studied complex of diffuse gas and dust clouds in our Milky Way Galaxy. In a few billion years, only one galaxy will remain.
Tomorrow’s picture: incredible crab 1
星系大战: M81对战M82
影像提供与版权: Collaborative Astrophotography Team (CAT)
说明: 位于视野左上角、拥有蓝色旋臂、上头散布着泛红星云的星系，是螺旋星系M81。而位在视野右下角落的，则是披着白色横带、有泛红发光气体环拱的不规则星系M82。这幅精采影像的主角，即是在过去的十亿年里，这二个不断透过重力进行缠斗的庞大星系。在每次为期亿年的近距离摖身而过之中，它们的重力对彼此都产生了重大的影响。于最近一轮的缠斗中，M82的重力在M81的星系盘上，触发盘旋不息的密度波，并造就了M81壮观的旋臂。而M81则在M82里，产生了许多猛暴的恒星形成区及剧烈的星云碰撞，并让它发出明亮的X射线辉光。从地球看出去，视线得穿过银河系鲜少被探索的昏暗共照耀星云复合体，才能见到这场大战。 而在接下来的数十亿年之中，它们终将合并成单一星系。
明日的图片: incredible crab 1
