銀河系會與仙女座星系發(fā)生碰撞嗎？會！

Will our Milky Way Galaxy collide one day with its larger neighbor, the Andromeda Galaxy? Most likely, yes. Careful plotting of slight displacements of M31's stars relative to background galaxies on recent Hubble Space Telescope images indicate that the center of M31 could be on a direct collision course with the center of our home galaxy. Still, the errors in sideways velocity appear sufficiently large to admit a good chance that the central parts of the two galaxies will miss, slightly, but will become close enough for their outer halos to become gravitationally entangled. Once that happens, the two galaxies will become bound, dance around, and eventually merge to become one large elliptical galaxy -- over the next few billion years. Pictured here is a combination of images depicting the sky of a world (Earth?) in the distant future when the outer parts of each galaxy begin to collide. The exact future of our Milky Way and the entire surrounding Local Group of Galaxies is likely to remain an active topic of research for years to come.?

我們的銀河系有一天會與其更大的鄰居仙女座星系發(fā)生碰撞嗎？很可能是的。在哈勃太空望遠鏡最近拍攝的圖像上，仔細繪制了M31恒星相對于背景星系的輕微位移圖，表明M31的中心可能與我們所在星系的中心發(fā)生直接碰撞。盡管如此，橫向速度的誤差似乎足夠大，這兩個星系的中心部分很有可能會稍微偏離，但會變得足夠近，使它們的外暈在重力作用下糾纏在一起。一旦發(fā)生這種情況，這兩個星系將結合在一起，跳舞，最終合并成一個巨大的橢圓星系——在接下來的數(shù)十億年里。這里的圖片是一組描繪世界天空（地球？）在遙遠的將來，當每個星系的外部開始碰撞時。我們銀河系和周圍整個星系群的確切未來可能在未來幾年內(nèi)仍然是一個活躍的研究課題。