Copyright:Malcolm Park
原文:
Separated by about 14 degrees (28 Full Moons) in planet Earth’s sky, spiral galaxies M31 at left, and M33 are both large members of the Local Group, along with our own Milky Way galaxy. This narrow- and wide-angle, multi-camera composite finds details of spiral structure in both, while the massive neighboring galaxies seem to be balanced in starry fields either side of bright Mirach, beta star in the constellation Andromeda. Mirach is just 200 light-years from the Sun. But M31, the Andromeda Galaxy, is really 2.5 million light-years distant and M33, the Triangulum Galaxy, is also about 3 million light years away. Although they look far apart, M31 and M33 are engaged in a gravitational struggle. In fact, radio astronomers have found indications of a bridge of neutral hydrogen gas that could connect the two, evidence of a closer encounter in the past. Based on measurements, gravitational simulations currently predict that the Milky Way, M31, and M33 will all undergo mutual close encounters and potentially mergers, billions of years in the future.
中文翻譯:
在地球的天空中，M31（安達魯斯星系）和M33（三角座星系）相距約14度（28個滿月），這兩個螺旋星系是本地團的主要成員，還有我們的銀河系。這張窄角和廣角的多相機合成圖展示了兩個星系的螺旋結構細節，而這些巨大的鄰近星系在明亮的米拉克（Mirach），即仙女座的β星兩側看起來均衡。米拉克距離太陽僅200光年；但是M31，即安達魯斯星系，實際上距離我們2.5百萬光年，而M33，即三角座星系，則大約是300萬光年遠。雖然它們看起來相距甚遠，但M31和M33實際上正在進行引力上的鬥爭。事實上，無線電天文學家已發現存在一條可能連接兩者的中性氫氣橋，這表明它們在過去曾經發生過更近的交會。根據測量結果，目前的引力模擬預測，銀河系、M31和M33將在未來的數十億年內進行相互的近距離交會，甚至可能合併。
#銀河系 #安達魯斯星系 #三角座星系 #星際探索 #天文學 #星系合併 #宇宙奇觀 #米拉克 #本地團 #引力互動
來源:NASA每日圖片
