NGC 7822：宇宙级的问号

NGC 7822：宇宙级的问号

ByNASA中文

2021年10月13日 NGC 7822: Cosmic Question Mark Image Credit & Copyright: Yizhou Zhang Explanation: It may look like a huge cosmic question mark, but the big question really is how does the bright gas and dark dust tell this nebula’s history of star formation. At the edge of a giant molecular cloud toward the northern constellation Cepheus, the glowing star forming region NGC 7822 lies about 3,000 light-years away. Within the nebula, bright edges and dark shapes stand out in this colorful and detailed skyscape. The 9-panel mosaic, taken over 28 nights with a small telescope in Texas, includes data from narrowband filters, mapping emission from atomic oxygen, hydrogen, and sulfur into blue, green, and red hues. The emission line and color combination has become well-known…

林茨暗星云1251

林茨暗星云1251

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2021年9月20日 Lynds Dark Nebula 1251 Image Credit & Copyright: Cristiano Gualco Explanation: Stars are forming in Lynds Dark Nebula (LDN) 1251. About 1,000 light-years away and drifting above the plane of our Milky Way galaxy, the dusty molecular cloud is part of a complex of dark nebulae mapped toward the Cepheus flare region. Across the spectrum, astronomical explorations of the obscuring interstellar clouds reveal energetic shocks and outflows associated with newborn stars, including the telltale reddish glow from scattered Herbig-Haro objects hiding in the image. Distant background galaxies also lurk on the scene, almost buried behind the dusty expanse. This alluring view spans over two full moons on the sky, or 17 light-years at the estimated distance of LDN 1251. Tomorrow’s picture: sun spot hill…

M16特写

M16特写

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2021年9月9日 M16 Cose Up Image Credit & Copyright: Martin Pugh Explanation: A star cluster around 2 million years young surrounded by natal clouds of dust and glowing gas, M16 is also known as The Eagle Nebula. This beautifully detailed image of the region adopts the colorful Hubble palette and includes cosmic sculptures made famous in Hubble Space Telescope close-ups of the starforming complex. Described as elephant trunks or Pillars of Creation, dense, dusty columns rising near the center are light-years in length but are gravitationally contracting to form stars. Energetic radiation from the cluster stars erodes material near the tips, eventually exposing the embedded new stars. Extending from the ridge of bright emission left of center is another dusty starforming column known as the Fairy…

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…

南冕座的恒星和尘埃

南冕座的恒星和尘埃

ByNASA中文

2021年8月6日 Stars and Dust Across Corona Australis Image Credit & Copyright: Vikas Chander Explanation: Cosmic dust clouds cross a rich field of stars in this telescopic vista near the northern boundary of Corona Australis, the Southern Crown. Less than 500 light-years away the dust clouds effectively block light from more distant background stars in the Milky Way. Top to bottom the frame spans about 2 degrees or over 15 light-years at the clouds’ estimated distance. At top right is a group of lovely reflection nebulae cataloged as NGC 6726, 6727, 6729, and IC 4812. A characteristic blue color is produced as light from hot stars is reflected by the cosmic dust. The dust also obscures from view stars in the region still in the process…

天蝎座的黑塔星云

天蝎座的黑塔星云

ByNASA中文

2021年7月15日 The Dark Tower in Scorpius Image Credit & Copyright: Data – Martin Pugh Processing – Rocco Sung Explanation: In silhouette against a crowded star field along the tail of the arachnalogical constellation Scorpius, this dusty cosmic cloud evokes for some the image of an ominous dark tower. In fact, clumps of dust and molecular gas collapsing to form stars may well lurk within the dark nebula, a structure that spans almost 40 light-years across this gorgeous telescopic portrait. Known as a cometary globule, the swept-back cloud, is shaped by intense ultraviolet radiation from the OB association of very hot stars in NGC 6231, off the upper edge of the scene. That energetic ultraviolet light also powers the globule’s bordering reddish glow of hydrogen gas….

模拟：第一代恒星的形成

模拟：第一代恒星的形成

ByNASA中文

2021年06月30日 Simulation: Formation of the First Stars Video Credit: Harley Katz (U. Oxford) et al. Explanation: How did the first stars form? To help find out, the SPHINX computer simulation of star formation in the very early universe was created, some results of which are shown in the featured video. Time since the Big Bang is shown in millions of years on the upper left. Even 100 million years after the Big Bang, matter was spread too uniformly across the cosmos for stars to be born. Besides background radiation, the universe was dark. Soon, slight matter clumps rich in hydrogen gas begin to coalesce into the first stars. In the time-lapse video, purple denotes gas, white denotes light, and gold shows radiation so energetic that…

星力的恒星形成模拟

星力的恒星形成模拟

ByNASA中文

2021年06月23日 STARFORGE: A Star Formation Simulation Video & Text Credit: Michael Y. Grudić (Northwestern U.) et al., STARFORGE Collaboration; Music: Prelude, Op. 28, No. 4 in E Minor (Frédéric Chopin) Explanation: How do stars form? Most form in giant molecular clouds located in the central disk of a galaxy. The process is started, influenced, and limited by the stellar winds, jets, high energy starlight, and supernova explosions of previously existing stars. The featured video shows these complex interactions as computed by the STARFORGE simulation of a gas cloud 20,000 times the mass of our Sun. In the time-lapse visualization, lighter regions indicate denser gas, color encodes the gas speed (purple is slow, orange is fast), while dots indicate the positions of newly formed stars. As…

礁湖星云的南崖

礁湖星云的南崖

ByNASA中文

2021年05月15日 The Southern Cliff in the Lagoon Image Credit: Julia I. Arias and Rodolfo H. Barba’ (Dept. Fisica, Univ. de La Serena), ICATE-CONICET, Gemini Observatory/AURA Explanation: Undulating bright ridges and dusty clouds cross this close-up of the nearby star forming region M8, also known as the Lagoon Nebula. A sharp, false-color composite of narrow band visible and broad band near-infrared data from the 8-meter Gemini South Telescope, the entire view spans about 20 light-years through a region of the nebula sometimes called the Southern Cliff. The highly detailed image explores the association of many newborn stars imbedded in the tips of the bright-rimmed clouds and Herbig-Haro objects. Abundant in star-forming regions, Herbig-Haro objects are produced as powerful jets emitted by young stars in the process…

火焰星云之内

火焰星云之内

ByNASA中文

2021年04月17日 Inside the Flame Nebula Image Credit: NASA, JPL-Caltech, IPAC Infrared Science Archive – Processing: Amal Biju Explanation: The Flame Nebula is a stand out in optical images of the dusty, crowded star forming regions toward Orion’s belt and the easternmost belt star Alnitak, a mere 1,400 light-years away. Alnitak is the bright star at the right edge of this infrared image from the Spitzer Space Telescope. About 15 light-years across, the infrared view takes you inside the nebula’s glowing gas and obscuring dust clouds though. It reveals many stars of the recently formed, embedded cluster NGC 2024 concentrated near the center. The stars of NGC 2024 range in age from 200,000 years to 1.5 million years young. In fact, data indicate that the youngest…