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11月19日:NGC 7822：红外光波段的恆星与尘埃柱-（NGC 7822: Stars and Dust Pillars in Infrared） 2017年11月19日:NGC 7822：红外光波段的恆星与尘埃柱-（NGC 7822: Stars and Dust Pillars in Infrared）--原图下载{mtitle title="NGC 7822：红外光波段的恆星与尘埃柱"/}Image Credit: WISE, IRSA, NASA; Processing & Copyright :Francesco Antonucci说明: 在NGC 7822之内，年轻的恒星正在清扫孕育它们的育婴室。在这幅由美国航太总署．广角红外光巡天卫星 (WISE)为这个星云拍摄的细緻红外光影像里，明亮的云气脊和绵延的尘埃柱是最醒目的结构。NGC 7822则是座落在北天仙王座方向，一个庞大分子云边缘的明亮恒星形成区，离我们大约有3,000光年远。而在星团炽热成员星的高能辐射激发下，除了让云气的原子发光之外，强烈的恒星风和星光更雕塑和侵蚀了较緻密的尘埃柱。在云柱之内，重力塌缩可能仍然持续在形成恒星，但随着云柱侵蚀殆尽，任何形成中的恒星，都会失去造星物质的储存库。以NGC 7822的距离来换算，这张影像约莫涵盖40光年宽的区域。{lamp/}原文：{mtitle title="NGC 7822: Stars and Dust Pillars in Infrared"/}Image Credit: WISE, IRSA, NASA; Processing & Copyright :Francesco AntonucciExplanation: Young stars themselves are clearing out their nursery in NGC 7822.Within the nebula, bright edges and complex dust sculptures dominate thisdetailed skyscape taken in infrared light by NASA's Wide Field Infrared Survey Explorer (WISE) satellite.NGC 7822 lies at the edge of a giantmolecular cloud toward the northernconstellationCepheus, a glowing star forming region that lies about 3,000 light-years away.The atomic emission of light by the nebula's gas ispowered by energetic radiation fromthe hot stars, whose powerful winds and light also sculptand erode the denser pillar shapes.Stars could still be forminginside the pillars by gravitational collapse, but as the pillars areeroded away, any forming stars will ultimately be cut off from their reservoir ofstar stuff.This field spans around 40 light-years at the estimated distance of NGC 7822.

2017年11月08日:NGC 2261： 哈伯变光星云-（NGC 2261: Hubble's Variable Nebula） 2017年11月08日:NGC 2261： 哈伯变光星云-（NGC 2261: Hubble's Variable Nebula）--原图下载{mtitle title="NGC 2261： 哈伯变光星云"/}Image Credit: Hubble, NASA, ESA; Data: Mark Clampin (NASA's GSFC); Processing & License: Judy Schmidt说明: 哈伯变光星云的亮度为何会有变化呢？这幅主题影像呈现的不寻常星云，外观在数星期内就会有明显的变化。发现于200多年前，后来被编录为NGC 2661的这团精采星云。因为哈伯曾在上世纪初研究过它，所以有哈伯星云的称号。或许更为恰当的与举动是，使用以哈伯为名的太空望远镜，来为这团不寻常的星云拍摄这幅主题影像。哈伯变光星云是一团反射星云，主要成分是由从麒麟座R星绵延出来的气体和尘埃。这团昏暗的星云，大小约有1光年，位在南天的麒麟座方向，距离我们约有2,500光年远。最可信的变光假说指出，麒麟座R星的附近可能有许多集结成团的尘埃，当这些不透光的尘埃团通过这颗星附近时，它们的暗影就投射在这个星云上，造成哈伯变光星云出现变光。{lamp/}原文：{mtitle title="NGC 2261: Hubble's Variable Nebula"/}Image Credit: Hubble, NASA, ESA; Data: Mark Clampin (NASA's GSFC); Processing & License: Judy SchmidtExplanation: What causes Hubble's Variable Nebula to vary? The unusual nebula featured here changes its appearance noticeably in just a few weeks. Discovered over 200 years ago and subsequently cataloged as NGC 2261, the remarkable nebula is named for Edwin Hubble, who studied it early last century. Fitting, perhaps, the featured image was taken by another namesake of Hubble: the Space Telescope.Hubble's Variable Nebula is a reflection nebula made of gas and fine dust fanning out from the star R Monocerotis. The faint nebula is about one light-year across and lies about 2500 light-years away towards the constellation of the Unicorn (Monocerotis). The leading variability explanation for Hubble's Variable Nebula holds that dense knots of opaque dust pass close to R Mon and cast moving shadows onto the reflecting dust seen in the rest of the nebula.

2017年09月13日: NGC 6334: 猫掌星云-（NGC 6334: The Cat's Paw Nebula） 2017年09月13日: NGC 6334: 猫掌星云-（NGC 6334: The Cat's Paw Nebula）--原图下载{mtitle title=" NGC 6334: 猫掌星云"/}Image Credit & Copyright: George Varouhakis说明: 星云会因酷似我们常见的形状而声名大噪，就像猫因经常闯祸而出了名一样。不过，没有猫能创造出这个位在天蝎座内的巨大猫掌星云。离我们5,500光年远的猫掌星云是个发射星云，它红色的辉光来自大量电离的氢原子。亦拥有熊掌星云或NGC 6334称号的猫掌星云，内部质量接近十倍太阳质量的恒星，是近在过去数百万年内才从这个星云诞生出来的。上面这幅猫掌星云的深空影像，摄于原子氢、氧和硫发光的波段。{lamp/}原文：{mtitle title="NGC 6334: The Cat's Paw Nebula"/}Image Credit & Copyright: George VarouhakisExplanation: Nebulas are perhaps as famous for being identified with familiar shapes as perhaps cats are for getting into trouble. Still, no known cat could have created the vast Cat's Paw Nebula visible in Scorpius. At 5,500 light years distant, Cat's Paw is an emission nebula with a red color that originates from an abundance of ionized hydrogen atoms. Alternatively known as the Bear Claw Nebula or NGC 6334, stars nearly ten times the mass of our Sun have been born there in only the past few million years.Pictured here is a deep field image of the Cat's Paw Nebula in light emitted by hydrogen, oxygen, and sulfur.

2016年07月04日:IC 4628: 斑节虾星云-（IC 4628: The Prawn Nebula） 2016年07月04日:IC 4628: 斑节虾星云-（IC 4628: The Prawn Nebula）--原图下载{mtitle title="IC 4628: 斑节虾星云"/}Image Credit & Copyright: Michael Sidonio说明: 在心宿二之南，在满布星云的天蝎座尾部，座落着发射星云IC 4628。附近众多年龄只有数百万年的年轻大质量恒星，以不可见的紫外辐射照射这个星云，把电子从原子中剥离出来；电子后来再和原子复合，产生以氢红光为主的可见星云辉光。这片天区所涵盖的面积大约和4个满月相当，以此星云6,000光年的距离来换算，此区域的宽度大约为250光年。因为澳洲天文学家干姆编录的星表，这个星云的另一个编录号是Gum 56，但酷爱海鲜的天文学家可能也知道，这个星云拥有斑节虾星云的雅号。(Prawn Nebula 斑节虾星云){lamp/}原文：{mtitle title="IC 4628: The Prawn Nebula"/}Image Credit & Copyright: Michael SidonioExplanation: South of Antares, in the tail ofthe nebula-rich constellationScorpius, lies emission nebulaIC 4628.Nearby hot, massive stars, millions of years young,irradiate thenebula with invisible ultraviolet light, stripping electronsfrom atoms.The electrons eventually recombine with the atoms to produce the visiblenebular glow,dominated by the red emission of hydrogen.At an estimated distance of 6,000 light-years, the region shownis about 250 light-years across, spanning an area equivalent tofour full Moons on the sky.The nebula is alsocataloged as Gum 56 for Australian astronomer Colin Stanley Gum,but seafood-loving astronomers mightknow this cosmic cloud as the Prawn Nebula.

2013年09月23日:IC 4628: 斑节虾星云-（IC 4628: The Prawn Nebula） 2013年09月23日:IC 4628: 斑节虾星云-（IC 4628: The Prawn Nebula）--原图下载{mtitle title="IC 4628: 斑节虾星云"/}Credit: ESO; Acknowledgement: Martin Pugh说明: 在心宿二的南边，亦即在满是星云的天蝎座尾部，可以找到发射星云IC 4628。附近众多年龄只有数百万年的年轻大质量恒星，辐射出不可见的紫外线照射这个星云，把电子从原子中剥离出来；而电子最后与原子复合，产生以氢红光为主的星云可见辉光。这张照片大约涵盖了4个满月的天区，以这个区域6,000光年的距离来估算，相当于是250光年的範围。这个星云的另一个编录号是Gum 56，源自澳洲天文学家干姆 (Colin Stanley Gum)的编录，但酷爱海鲜的天文学家可能也知道，这个星云有个斑节虾星云 (the Prawn Nebula)的俗称。{lamp/}原文：{mtitle title="IC 4628: The Prawn Nebula"/}Credit: ESO; Acknowledgement: Martin PughExplanation: South of Antares, in the tail ofthe nebula-rich constellationScorpius, lies emission nebulaIC 4628.Nearby hot, massive stars, millions of years young,radiate thenebula with invisible ultraviolet light, stripping electronsfrom atoms.The electrons eventually recombine with the atoms to produce the visiblenebular glow,dominated by the red emission of hydrogen.At an estimated distance of 6,000 light-years, the region shownis about 250 light-years across, spanning an area equivalent tofour full moons on the sky.The nebula is alsocataloged as Gum 56 for Australian astronomer Colin Stanley Gum,but seafood-loving astronomers mightknowthis cosmic cloud as The Prawn Nebula.