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A relatively nearby galaxy that closely resembles our own Milky Way can be seen edge-on in a new image. |
一个较近的星系酷似我们的银河系，在一张新图片中可以看到它的侧面。 |
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Observations of the galaxy, NGC 4945, suggest that this hive of stars is a spiral galaxy much like our own, with swirling, luminous arms and a bar-shaped central region. |
星系NGC4945的观测资料显示：这一群恒星是一个漩涡星系，有着明亮的旋臂和棒状的中心区域，在很大程度上类似我们的银河系。 |
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But that's where the similarity seems to end: NGC 4945 has a brighter center than the Milky Way; the look-alike's center likely harbors a supermassive black hole that is devouring reams of matter and blasting energy out into space. |
然而，相似之处好象到此为止。NGC4945的中心比银河系更加明亮，其中心很可能拥有一个超大质量的黑洞，正在吞噬大量的物质，并且向太空喷发着巨大的能量。 |
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The new portrait of NGC 4945, which lies some 13 million light-years away in the constellation of Centaurus, was taken by the Wide Field Imager (WFI) instrument at the 2.2-metre MPG/ESO telescope at the La Silla Observatory in Chile. |
NGC4945位于人马座，大约在1,300万光年之外。这张新图像是由智利拉息拉天文台2.2米MPG/ESO望远镜上搭载的宽视野摄像仪(WFI)拍摄的。 |
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NGC 4945 appears cigar-shaped from our perspective on Earth, but the galaxy is actually a disc many times wider than it is thick, with bands of stars and glowing gas spiraling around its center. Other spiral galaxies, like ours, are similarly flattened and typically contain a central bulge of stars around a black hole. |
从地球的角度来看，星系NGC4945就象一根雪茄，但实际上该星系是圆盘状的，其直径是厚度的许多倍。排列成条状的恒星以及炽热的气体在中心周围盘旋。其他的漩涡星系跟银河系一样，呈扁平状，在黑洞周围通常包含一个由恒星构成的中心凸出区。 |
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Special filters on the telescope isolate the color of light emitted by heated gases such as hydrogen, showing sharp contrasts in NGC 4945 that indicate areas of star formation. |
该望远镜上的特殊滤光片把高温气体（如：氢气）所释放的光色分离出去，使星系NGC4945的图像对比非常清晰，显示出其中的恒星形成区。 |
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Other observations have revealed that NGC 4945 has an active galactic nucleus, meaning its central bulge emits far more energy than calmer galaxies like the Milky Way. |
其他的观测资料显示，NGC4945拥有一个活动星系核，这意味着：跟象银河系这样比较平静的星系相比，其中心的凸出区域所释放的能量要多得多。 |
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Black holes gravitationally draw gas and dust into them, accelerating and heating this attracted matter until it emits high-energy radiation, including X-rays and ultraviolet light. Most large, spiral galaxies, including the Milky Way, host a black hole in their centers, though many of these dark monsters no longer actively "feed" at this stage in galactic development. |
黑洞的引力将气体和尘埃吸进来，并使吸进的物质加速升温，直到释放出高能辐射，包括X射线和紫外光。包括银河系在内的多数大型漩涡星系，都在中心区域“招待着”一个黑洞。然而，在星系演化的这个阶段，许多“黑怪”已经不再活跃地“进食”。 |
