美丽的三叶星云

美丽的三叶星云

ByNASA中文

2021年8月12日 A Beautiful Trifid Image Credit & Copyright: Mike Selby Explanation: The beautiful Trifid Nebula is a cosmic study in contrasts. Also known as M20, it lies about 5,000 light-years away toward the nebula rich constellation Sagittarius. A star forming region in the plane of our galaxy, the Trifid does illustrate three different types of astronomical nebulae; red emission nebulae dominated by light from hydrogen atoms, blue reflection nebulae produced by dust reflecting starlight, and dark nebulae where dense dust clouds appear in silhouette. But the red emission region roughly separated into three parts by obscuring dust lanes is what lends the Trifid its popular name. Pillars and jets sculpted by newborn stars, below and left of the emission nebula’s center, appear in famous Hubble…

IC 4592：蓝马头反射星云

IC 4592：蓝马头反射星云

ByNASA中文

2021年07月05日 IC 4592: The Blue Horsehead Reflection Nebula Image Credit & Copyright: Adam Block, Steward Observatory, University of Arizona Explanation: Do you see the horse’s head? What you are seeing is not the famous Horsehead nebula toward Orion but rather a fainter nebula that only takes on a familiar form with deeper imaging. The main part of the here imaged molecular cloud complex is a reflection nebula cataloged as IC 4592. Reflection nebulas are actually made up of very fine dust that normally appears dark but can look quite blue when reflecting the visible light of energetic nearby stars. In this case, the source of much of the reflected light is a star at the eye of the horse. That star is part of Nu…

M78的大视野影像

M78的大视野影像

ByNASA中文

2021年01月21日 M78 Wide Field Image Credit & Copyright: Wes Higgins Explanation: Interstellar dust clouds and glowing nebulae abound in the fertile constellation of Orion. One of the brightest, M78, is centered in this colorful, wide field view, covering an area north of Orion’s belt. At a distance of about 1,500 light-years, the bluish reflection nebula is around 5 light-years across. Its tint is due to dust preferentially reflecting the blue light of hot, young stars. Reflection nebula NGC 2071 is just to the left of M78. Flecks of emission from Herbig-Haro objects, energetic jets from stars in the process of formation, stand out against the dark dust lanes. The exposure also brings out the region’s fainter, pervasive reddish glow of atomic hydrogen gas. Tomorrow’s picture:…

狐皮、独角兽与圣诞树

狐皮、独角兽与圣诞树

ByNASA中文

2020年12月26日 Fox Fur, Unicorn, and Christmas Tree Image Credit & Copyright: Miguel Claro (TWAN, Dark Sky Alqueva) Explanation: Clouds of glowing hydrogen gas fill this colorful skyscape in the faint but fanciful constellation Monoceros, the Unicorn. A star forming region cataloged as NGC 2264, the complex jumble of cosmic gas and dust is about 2,700 light-years distant and mixes reddish emission nebulae excited by energetic light from newborn stars with dark interstellar dust clouds. Where the otherwise obscuring dust clouds lie close to the hot, young stars they also reflect starlight, forming blue reflection nebulae. The telescopic image spans about 1.5 degrees or 3 full moons, covering nearly 80 light-years at the distance of NGC 2264. Its cast of cosmic characters includes the the Fox…

星云IC 2118的食尸鬼

星云IC 2118的食尸鬼

ByNASA中文

2020年10月29日 The Ghoul of IC 2118 Image Credit & Copyright: Casey Good/Steve Timmons Explanation: Inspired by the halloween season, this telescopic portrait captures a cosmic cloud with a scary visage. The interstellar scene lies within the dusty expanse of reflection nebula IC 2118 in the constellation Orion, the Hunter. IC 2118 is about 800 light-years from your neighborhood, close to bright bluish star Rigel at Orion’s foot. Often identified as the Witch Head nebula for its appearance in a wider field of view it now rises before the witching hour. With spiky stars for eyes, the ghoulish apparition identified here seems to extend an arm many light-years long toward Orion’s hot supergiant star. The source of illumination for IC 2118, Rigel is just beyond this…

鬼魂星魂

鬼魂星魂

ByNASA中文

2020年10月26日 Reflections of the Ghost Nebula Image Credit & Copyright: Bogdan Jarzyna Explanation: Do any shapes seem to jump out at you from this interstellar field of stars and dust? The jeweled expanse, filled with faint, starlight-reflecting clouds, drifts through the night in the royal constellation of Cepheus. Far from your own neighborhood on planet Earth, these ghostly apparitions lurk along the plane of the Milky Way at the edge of the Cepheus Flare molecular cloud complex some 1,200 light-years away. Over two light-years across and brighter than the other spooky chimeras, VdB 141 or Sh2-136 is also known as the Ghost Nebula, seen at toward the bottom of the featured image. Within the reflection nebula are the telltale signs of dense cores collapsing in…

麒麟座的星云

麒麟座的星云

ByNASA中文

2020 February 8 Cosmic Clouds in the Unicorn Image Credit & Copyright: Bray Falls Explanation: Interstellar clouds of hydrogen gas and dust abound in this gorgeous skyscape. The 3 degree wide field of view stretches through the faint but fanciful constellation Monoceros, the Unicorn. A star forming region cataloged as NGC 2264 is centered, a complex jumble of cosmic gas, dust and stars about 2,700 light-years distant. It mixes reddish emission nebulae excited by energetic light from newborn stars with dark dust clouds. Where the otherwise obscuring dust clouds lie close to hot, young stars they also reflect starlight, forming blue reflection nebulae. A few light-years across, a simple sculpted shape known as the Cone Nebula is near center. Outlined by the red glow of…

南冕座的恒星和尘埃

南冕座的恒星和尘埃

ByNASA中文

2020 January 12 Stars and Dust in Corona Australis Image Credit & Copyright: CHART32 Team, Processing – Johannes Schedler Explanation: Cosmic dust clouds and young, energetic stars inhabit this telescopic vista, less than 500 light-years away toward the northern boundary of Corona Australis, the Southern Crown. The dust clouds effectively block light from more distant background stars in the Milky Way. But the striking complex of reflection nebulae cataloged as NGC 6726, 6727, and IC 4812 produce a characteristic blue color as light from the region’s young hot stars is reflected by the cosmic dust. The dust also obscures from view stars still in the process of formation. At the left, smaller yellowish nebula NGC 6729 bends around young variable star R Coronae Australis. Just…

仙后座内的幽灵

仙后座内的幽灵

ByNASA中文

2019 October 25 The Ghosts of Cassiopeia Image Credit & Copyright: Tommaso Stella Explanation: These bright rims and flowing shapes look ghostly on a cosmic scale. A telescopic view toward the constellation Cassiopeia, the colorful skyscape features swept-back, comet-shaped clouds IC 59 (left) and IC 63. About 600 light-years distant, the clouds aren’t actually ghosts. They are slowly disappearing though, under the influence of energetic radiation from hot,luminous star gamma Cas. Gamma Cas is physically located only 3 to 4 light-years from the nebulae, the bright star just above and left in the frame. Slightly closer to gamma Cas, IC 63 is dominated by red H-alpha light emitted as hydrogen atoms ionized by the star’s ultraviolet radiation recombine with electrons. Farther from the star, IC…

尘埃场内的鸢尾花星云

尘埃场内的鸢尾花星云

ByNASA中文

2019 September 12 The Iris Nebula in a Field of Dust Image Credit & Copyright: Markus Bauer Explanation: These cosmic dust clouds drift some 1,300 light-years away along the fertile starfields of the constellation Cepheus. The beautiful Iris Nebula, also known as NGC 7023, blossoms at the upper left. Not the only nebula in the sky to evoke the imagery of flowers, its pretty, symmetric form spans about 6 light-years. This nebula’s dominant blue color is characteristic of the pervasive dust grains reflecting light from a nearby hot, bluish star. But darker, obscuring dust clouds cover most of the nearly 4 degree wide field of view. At the right is the LDN 1147/1158 complex of Lynds Dark Nebulae. Stars are forming there, still hidden within…