2017年11月29日:M42：猎户座大星云-（M42: The Great Orion Nebula） 2017年11月29日:M42：猎户座大星云-（M42: The Great Orion Nebula）--原图下载{mtitle title="M42：猎户座大星云"/}Image Credit & Copyright: Francesco Battistella说明: 鲜少有天文景观能像着名的猎户座星云，这个邻近的恒星育婴室这么善于激发着人们的想像。这个星云的辉光云气，环拱着位在一个庞大星际分子云里的炽热年轻恒星。而在这幅主题影像里的许多丝状云气结构，事实上是激波前沿，在该处，高速移动的物质遇到慢速移动的气体。跨幅约40光年、距离约1,500光年的猎户座大星云，和太阳都位在银河系的同一道旋臂上。座落在着名猎户座内、轻易可辨的腰带三星左下方之猎户座大星云，是个肉眼可见天体。上面这幅主题照片，是在上个月使用2小时长曝光拍摄的三色影像。包括马头星云在内的整个猎户座星云複合体，在接下来的100,000年之内，会慢慢的散开来。{lamp/}原文：{mtitle title="M42: The Great Orion Nebula"/}Image Credit & Copyright: Francesco BattistellaExplanation: Few astronomical sights excite the imagination like the nearby stellar nursery known as the Orion Nebula. The Nebula's glowing gas surrounds hot young stars at the edge of an immense interstellar molecular cloud. Many of the filamentary structures visible in the featured image are actually shock waves - fronts where fast moving material encounters slow moving gas. The Orion Nebula spans about 40 light years and is located about 1500 light years away in the same spiral arm of our Galaxy as the Sun. The Great Nebula in Orion can be found with the unaided eye just below and to the left of the easily identifiable belt of three stars in the popular constellation Orion. The featured image, taken last month, shows a two-hour exposure of the nebula in three colors.The whole Orion Nebula cloud complex, which includes the Horsehead Nebula, will slowly disperse over the next 100,000 years.

2017年10月02日:彗星与星团-（Two Comets and a Star Cluster） [2017年10月02日:彗星与星团-（Two Comets and a Star Cluster）--原图下载](https://apod.nasa.gov/apod/image/1710/PleiadesComets_Peach_2081.jpg"onMouseOver="if (document.images)document.imagename1.src='image/1710/PleiadesComets_Peach_1080_annotated.jpg';"onMouseOut="if (document.images)document.imagename1.src='image/1710/PleiadesComets_Peach_1080.jpg';){mtitle title="彗星与星团"/}Image Credit &Copyright: Damian Peach说明: 二个不寻常光斑在着名的昴宿星团附近移动。这些每一晚只偏移一点点的光斑，其实是我们太阳系内围的彗星，恰好通过远在光年之遥的恒星前方。位在影像左缘的是彗星C/2017 O1 ASAS-SN，它是一团蒸发中宽达数公里的冰块，拥有主要受碳泛绿辐射渲染的气体彗发。而在彗星ASAS-SN1的右下方，可见到一道短短的彗尾。位在影像中央附近的是彗星C/2015 ER61 PanSTARRS，它除了也是一大团蒸发中的冰块之外，右侧更带着一道相当长的彗尾。影像右上角的昴宿星团，是一个由照亮邻近反射尘埃的泛蓝亮星聚成的疏散星团。这幅摄于2星期前的影像是如此深邃，所以整个视野里到处都是丝缕状的星际尘埃。昴宿星团是肉眼可见的天体，不过要透过双筒望远镜才看得到这二颗彗星。{lamp/}原文：{mtitle title="Two Comets and a Star Cluster"/}Image Credit &Copyright: Damian PeachExplanation: Two unusual spots are on the move near the famous Pleiades star cluster.Shifting only a small amount per night, these spots are actually comets in our nearby Solar System that by chance wandered into the field of the light-years distant stars. On the far left is comet C/2017 O1 ASAS-SN, a multi-kilometer block of evaporating ice sporting a bright coma of surrounding gas dominated by green-glowing carbon. Comet ASAS-SN1 shows a slight tail to its lower right. Near the frame center is comet C/2015 ER61 PanSTARRS, also a giant block of evaporating ice, but sporting a ratherlong tail to its right.On the upper right is the Pleiades, an open cluster dominated by bright blue stars illuminating nearby reflecting dust. This exposure, taken about two weeks ago, is so deep that the filamentary interstellar dust can be traced across the entire field.The Pleiades is visible to the unaided eye, but it should require binoculars to see the comets.

2016年07月27日:M13: 一个庞大的球状星团-（M13: A Great Globular Cluster of Stars） 2016年07月27日:M13: 一个庞大的球状星团-（M13: A Great Globular Cluster of Stars）--原图下载{mtitle title="M13: 一个庞大的球状星团"/}Image Credit & Copyright: Dean Fournier;Inset: ESA/Hubble & NASA说明: M13是地球夜空中最突出和最着名的球状星团之一。位在武仙座内，用双筒望远镜就能看见的M13，是观星人在观赏完肉眼可见的^天体珍宝之后，接下来经常会去寻找的进阶天体之一。M13是个由超过100,000颗恒星所组成的庞大天体，其大小超过150光年，距离超过2万光年，年龄则大于120亿年。在1974年阿雷西波天文台启用之时，曾朝着M13的方向传送一则含有地球资讯的电波讯息。这幅使用使用一部小望远镜及高动态範围成像技术拍摄的主题影像，视野涵盖的範围略大于一个满月；而特写星团中心0.04度範围的嵌图，则是由哈伯太空望远镜所拍摄。{lamp/}原文：{mtitle title="M13: A Great Globular Cluster of Stars"/}Image Credit & Copyright: Dean Fournier;Inset: ESA/Hubble & NASAExplanation: M13is one of the most prominent and best knownglobular clusters. Visible with binoculars in the constellation of Hercules, M13 is frequently one of the first objects found bycurious sky gazers seekingcelestials wondersbeyondnormal human vision. M13 is a colossal home to over 100,000 stars, spans over 150light years across,lies over 20,000 light years distant, and is over 12 billion years old. At the 1974 dedication ofArecibo Observatory, aradio messageabout Earth was sent in the direction ofM13. The featured imagein HDR, taken through a small telescope, spans an angular size just larger than a full Moon, whereas the inset image, taken by Hubble Space Telescope, zooms in on the central 0.04 degrees.

2013年12月04日:透过瑞典．摩尔比堡遗址看爱喜彗星-（Comet Lovejoy through M�rby Castle Ruins） 2013年12月04日:透过瑞典．摩尔比堡遗址看爱喜彗星-（Comet Lovejoy through M�rby Castle Ruins）--原图下载{mtitle title="透过瑞典．摩尔比堡遗址看爱喜彗星"/}Image Credit &Copyright: P-M Hedén (Clear Skies,TWAN)说明: 这颗新彗星相当上相。上星期在瑞典．摩尔比古堡 (Mörby Castle)遗址，拍摄三个月前刚发现的爱喜彗星时，见到它有个泛着绿晕的彗发而且拖着长达数度的彗尾。对彗星观察者来说，过去数週真是忙碌，因为同时出现了四颗双筒望远镜可见的彗星，分别有艾桑、爱喜 (Lovejoy)、恩克 (Encke)和丽霓儿 (LINEAR)。其中，爱喜彗星 (C/2013 R1)从幽暗地区观看正处于肉眼可见的阶段。由于新月(农曆初一)出现在星期一，接下来月光干扰较少的这几天，是观赏达到最大亮度的爱喜彗星之好时机。在二个半星期内，爱喜彗星将运行到最靠太阳的位置，届时，它刚好在地球道距离之内。{lamp/}原文：{mtitle title="Comet Lovejoy through M�rby Castle Ruins"/}Image Credit &Copyright: P-M Hedén (Clear Skies,TWAN)Explanation: This new comet is quite photogenic.Comet Lovejoy, discovered only three months ago, was imaged through ruins of ancient M�rby Castle in Sweden last week sporting a green-glowing coma and tails trailing several degrees.The past few weeks have been an unusually active time for comet watchers as four comets were visible simultaneously with binoculars: ISON, Lovejoy, Encke, and LINEAR.C/2013 R1 (Lovejoy) comet is currently visible to the unaided eye from a dark location.As Monday's new Moon will provide little glare, the next few days provide a good time to see Comet Lovejoy as it reaches its peak brightness.In two and a half weeks, Comet Lovejoy will reach its closest approach to the Sun at a distance just inside the orbital distance of the Earth.

2013年01月27日:智利上空的麦克诺彗星-（Comet McNaught Over Chile） 2013年01月27日:智利上空的麦克诺彗星-（Comet McNaught Over Chile）--原图下载{mtitle title="智利上空的麦克诺彗星"/}Image Credit & Copyright: St�phane Guisard说明: 在我们这个世代里，麦克诺彗星 (Comet McNaught)可能算是最为上相的彗星。2007年1月在北半球大展英姿之后，这个彗星就移到南天，并发展出一道不寻常的颀长彗尾，让南半球的观星人为之倾倒。上面影像呈现了这颗彗星出现在智利．圣地牙哥市上空的情景。从位在安地斯山脉的拍摄地点看出去，往上有麦克诺彗星和壮丽开阔的星空，前方有一轮弯弯的眉月，往下则可看到云层、大气尘霾和圣地牙哥市的灯火。2013年有机会看见更精彩的彗星；在3月初，泛星彗星 (Comet PANSTARRS)预期将增亮到肉眼可见，而在年底，艾松彗星 (Comet ISON)的演出，可能会包括横过整个天空的彗尾、裂解、及增亮到成为纪录中最明亮的彗星。{lamp/}原文：{mtitle title="Comet McNaught Over Chile"/}Image Credit & Copyright: St�phane GuisardExplanation: Comet McNaught of 2007 has been, so far, the most photogenic comet of our time. After makingquite a show in the northern hemispherein early 2007 January, the comet moved south and developed a long and unusual dust tail that dazzled southern hemisphere observers. In this image, Comet McNaught was captured above Santiago, Chile. The bright comet dominates on the left whilepart of its magnificent tail spreads across the entire frame. From this vantage point in the Andes Mountains, one looks up toward CometMcNaught and a magnificent sky,across at a crescent moon, and down on clouds, atmospheric haze,and the city lights.The current year -- 2013 -- holds promise to be even better for comets than 2007. In early March, Comet PANSTARRS is on track to become visible to the unaided eye, while at the end of the year Comet ISON shows possibilities that include casting a tail that spreads across the sky, breaking up, and even becoming one of the brightest comets in recorded history.

2011年09月28日:巨大的太阳黑子群AR 1302释放出闪焰-（Violent Sunspot Group AR 1302 Unleashes a Flare） 2011年09月28日:巨大的太阳黑子群AR 1302释放出闪焰-（Violent Sunspot Group AR 1302 Unleashes a Flare）--原图下载{mtitle title="巨大的太阳黑子群AR 1302释放出闪焰"/}Image Credit: jp-Brahic说明: 年度最大的一群黑子群(AR 1302)正在横跨太阳。上周，AR 1302初来到太阳边缘时，就已经大到肉眼可见。来自AR 1302日冕抛射物质诱发相当剧烈的地球磁暴，并且在地球两极均有显着的极光活动。上图中，AR 1302表面电浆使得磁场拱起于太阳表面，并且在上周四产生X级的日闪。在影像中插入地球为比例尺，虽然在星期六也产生了一次X级日闪，但是该次日闪并没有正对着地球。AR 1302黑子群将会继续发展，可能道下周还能看见他的蹤影。{lamp/}原文：{mtitle title="Violent Sunspot Group AR 1302 Unleashes a Flare"/}Image Credit: jp-BrahicExplanation: One of the most active sunspot groups in years is currently crossing the Sun.AR 1302 first came around the Sun's edge last week and is so large it can be seen without a telescope. Coronal Mass Ejections from AR 1302 have already caused strong geomagnetic storms including notable aurora activity around both of Earth's poles.Pictured above, plasma was left magnetically hanging above the Sun's surface after AR 1302 emitted an X-class solar flare last Thursday. Earth is illustrated in the inset for a size comparison.Although another X-class flare was emitted on Saturday, no flares from AR 1302 have been aimed directly at the Earth, as yet.The AR 1302 sunspot group will continue to evolve but likely remain visible on the Sun for the next week.