2016年07月25日:大、小麦哲伦星系的长曝光影像显示它们在互撞-（Deep Magellanic Clouds Image Indicates Collisions）--原图下载
Image Credit & Copyright: Yuri Beletsky(CarnegieLas Campanas Observatory,TWAN) & David Martinez-Delgado (U. Heidelberg)
说明: 我们银河最着名的二个伴星着曾经互撞吗？没人能说个准，但详细检视像主题影像这类的长曝光照片显示，它们确实曾经互撞。在这幅影像中，大麦哲伦星系位在左上角，而座落在右下方的是小麦哲伦星系。它们周围则环绕着单色反转星场影像，以突显用灰色呈现的暗淡恒星流。也许最令人惊讶的是，这幅研究等级的影像，是用小望远镜所拍摄，以涵盖将近40度的大张角星场。视野中大部分的云气，是位我们银河系之内的稀薄银河尘埃卷云；不过，暗淡的恒星流确实看似从小麦哲伦星系向大麦哲伦星系伸展。除此之外，小麦哲伦星系周围的恒星之分布也不对称，而电脑模拟显示这种分布可能是一次或多次互撞之中，被引力拉出来的结构。大麦哲伦星系与小麦哲伦星系，都是南天肉眼可见的天体；未来人类也必然会再对它们进行望远镜观测和电脑模拟，以为人类试图了解我们银河系和它周遭环境历史的持续努力之部分工作。
原文：
Image Credit & Copyright: Yuri Beletsky(CarnegieLas Campanas Observatory,TWAN) & David Martinez-Delgado (U. Heidelberg)
Explanation: Did the two most famous satellite galaxies of our Milky Way Galaxy once collide?No one knows for sure, but a detailed inspection of deep images like that featured here give an indication that they have.Pictured, the Large Magellanic Cloud (LMC) is on the top left and the Small Magellanic Cloud (SMC) is on the bottom right. The surrounding field is monochrome color-inverted to highlight faint filaments, shown in gray.Perhaps surprisingly, the featured research-grade image was compiled with small telescopes to cover the large angular field -- nearly 40 degrees across. Much of the faint nebulosity is Galactic Cirrus clouds of thin dust in our own Galaxy, but a faint stream of stars does appear to be extending from the SMC toward the LMC.Also, stars surrounding the LMC appear asymmetrically distributed, indicating in simulations that they could well have been pulled off gravitationally in one or more collisions. Both the LMC and the SMC are visible to the unaided eye in southern skies.Future telescopic observations and computer simulations are sure to continue in a continuing effort to better understand the history of our Milky Way and its surroundings.
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