模拟: 盘状星系的形成

模拟: 盘状星系的形成

ByNASA中文

2023年5月31日 Simulation: A Disk Galaxy Forms Video Credit: TNG Collaboration, MPCDF, FAS Harvard U.; Music: World’s Sunrise (YouTube: Jimena Contreras) Explanation: How did we get here? We know that we live on a planet orbiting a star orbiting a galaxy, but how did all of this form? Since our universe moves too slowly to watch, faster-moving computer simulations are created to help find out. Specifically, this featured video from the IllustrisTNG collaboration tracks gas from the early universe (redshift 12) until today (redshift 0). As the simulation begins, ambient gas falls into and accumulates in a region of relatively high gravity. After a few billion years, a well-defined center materializes from a strange and fascinating cosmic dance. Gas blobs — some representing small satellite galaxies…

邻近螺旋星系M101刚发现的超新星

邻近螺旋星系M101刚发现的超新星

ByNASA中文

2023年5月22日 Supernova Discovered in Nearby Spiral Galaxy M101 Image Credit & Copyright: Craig Stocks Explanation: A nearby star has exploded and humanity’s telescopes are turning to monitor it. The supernova, dubbed SN 2023ixf, was discovered by Japanese astronomer Koichi Itagaki three days ago and subsequently located on automated images from the Zwicky Transient Facility two days earlier. SN 2023ixf occurred in the photogenic Pinwheel Galaxy M101, which, being only about 21 million light years away, makes it the closest supernova seen in the past five years, the second closest in the past 10 years, and the second supernova found in M101 in the past 15 years. Rapid follow up observations already indicate that SN 2023ixf is a Type II supernova, an explosion that occurs after…

西班牙舞者螺旋星系

西班牙舞者螺旋星系

ByNASA中文

2023年5月8日 The Spanish Dancer Spiral Galaxy Image Credit: ESA, NASA, Hubble; Processing: Detlev Odenthal Explanation: If not perfect, then this spiral galaxy is at least one of the most photogenic. An island universe containing billions of stars and situated about 40 million light-years away toward the constellation of the Dolphinfish (Dorado), NGC 1566 presents a gorgeous face-on view. Classified as a grand design spiral, NGC 1566 shows two prominent and graceful spiral arms that are traced by bright blue star clusters and dark cosmic dust lanes. Numerous Hubble Space Telescope images of NGC 1566 have been taken to study star formation, supernovas, and the spiral’s unusually active center. Some of these images, stored online in the Hubble Legacy Archive, were freely downloaded, combined, and digitally…

星系NGC 3628

星系NGC 3628

ByNASA中文

2023年4月14日 Portrait of NGC 3628 Image Credit: Image Credit & Copyright: Mike Selby & Mark Hanson Explanation: Sharp telescopic views of NGC 3628 show a puffy galactic disk divided by dark dust lanes. Of course, this portrait of the magnificent, edge-on spiral galaxy puts some astronomers in mind of its popular moniker, the Hamburger Galaxy. It also reveals a small galaxy nearby (below), likely a satellite of NGC 3628, and a very faint but extensive tidal tail. The drawn out tail stretches for about 300,000 light-years, even beyond the left edge of the frame. NGC 3628 shares its neighborhood in the local universe with two other large spirals M65 and M66 in a grouping otherwise known as the Leo Triplet. Gravitational interactions with its cosmic…

M100: 宏伟的螺旋星系

M100: 宏伟的螺旋星系

ByNASA中文

2023年4月8日 M100: A Grand Design Spiral Galaxy Image Credit: NASA, ESA, Hubble; Processing: Judy Schmidt Explanation: Majestic on a truly cosmic scale, M100 is appropriately known as a grand design spiral galaxy. It is a large galaxy of over 100 billion stars with well-defined spiral arms that is similar to our own Milky Way Galaxy. One of the brightest members of the Virgo Cluster of galaxies, M100 (alias NGC 4321) is 56 million light-years distant toward the constellation of Berenice’s Hair (Coma Berenices). This Hubble Space Telescope image of M100 was taken with the Wide Field Camera 3 and accentuates bright blue star clusters and intricate winding dust lanes which are hallmarks of this class of galaxies. Studies of variable stars in M100 have played…

鲁宾的星系

鲁宾的星系

ByNASA中文

2023年4月5日 Rubin’s Galaxy Image Credit: NASA, ESA, B. Holwerda (University of Louisville) Explanation: In this Hubble Space Telescope image the bright, spiky stars lie in the foreground toward the heroic northern constellation Perseus and well within our own Milky Way galaxy. In sharp focus beyond is UGC 2885, a giant spiral galaxy about 232 million light-years distant. Some 800,000 light-years across compared to the Milky Way’s diameter of 100,000 light-years or so, it has around 1 trillion stars. That’s about 10 times as many stars as the Milky Way. Part of an investigation to understand how galaxies can grow to such enormous sizes, UGC 2885 was also part of An Interesting Voyage and astronomer Vera Rubin’s pioneering study of the rotation of spiral galaxies. Her…

螺旋星系NGC 2841

螺旋星系NGC 2841

ByNASA中文

2023年3月23日 Spiral Galaxy NGC 2841 Image Credit & Copyright: Roberto Marinoni Explanation: A mere 46 million light-years distant, spiral galaxy NGC 2841 can be found in planet Earth’s night sky toward the northern constellation of Ursa Major. This sharp image centered on the gorgeous island universe also captures spiky foreground Milky Way stars and more distant background galaxies within the same telescopic field of view. It shows off the bright nucleus of NGC 2841, along with its inclined galactic disk, and faint outer regions. Dust lanes, small star-forming regions, and young star clusters are embedded in the galaxy’s patchy, tightly wound spiral arms. In contrast, many other spirals exhibit broader, sweeping arms with large star-forming regions. NGC 2841 has a diameter of over 150,000 light-years,…

M31: 仙女星系

M31: 仙女星系

ByNASA中文

2023年3月22日 M31: The Andromeda Galaxy Image Credit & Copyright: Abdullah Al-Harbi Explanation: How far can you see? The most distant object easily visible to the unaided eye is M31, the great Andromeda Galaxy, over two million light-years away. Without a telescope, even this immense spiral galaxy appears as an unremarkable, faint, nebulous cloud in the constellation Andromeda. But a bright white nucleus, dark winding dust lanes, luminous blue spiral arms, and bright red emission nebulas are recorded in this stunning fifteen-hour telescopic digital mosaic of our closest major galactic neighbor. But how do we know this spiral nebula is really so far away? This question was central to the famous Shapley-Curtis debate of 1920. M31’s great distance was determined in the 1920s by observations that…

韦伯图像: 棒旋星系NGC 1365

韦伯图像: 棒旋星系NGC 1365

ByNASA中文

2023年2月18日 Barred Spiral Galaxy NGC 1365 from Webb Image Credit: NASA, ESA, CSA, Janice Lee (NOIRLab) – Processing: Alyssa Pagan (STScI) Explanation: A mere 56 million light-years distant toward the southern constellation Fornax, NGC 1365 is an enormous barred spiral galaxy about 200,000 light-years in diameter. That’s twice the size of our own barred spiral Milky Way. This sharp image from the James Webb Space Telescope’s Mid-Infrared Instrument (MIRI) reveals stunning details of this magnificent spiral in infrared light. Webb’s field of view stretches about 60,000 light-years across NGC 1365, exploring the galaxy’s core and bright newborn star clusters. The intricate network of dusty filaments and bubbles is created by young stars along spiral arms winding from the galaxy’s central bar. Astronomers suspect the gravity…

长蛇星系团

长蛇星系团

ByNASA中文

2023年2月16日 The Hydra Cluster of Galaxies Image Credit & Copyright: Marco Lorenzi, Angus Lau, Tommy Tse Text: ChatGPT (apologies to Edgar Allen Poe) Explanation: Once upon a midnight dreary, while I pondered weak and weary, O’er volumes of astronomy and forgotten lore, I stumbled upon this snapshot, cosmic and eerie, A sight that filled my heart with awe and more. Two stars, like sentinels, anchored the foreground, Of our Milky Way galaxy, a sight to behold, Beyond them, a cluster of Hydra, galaxies abound, 100 million light-years away, a story to be told. Three large galaxies, ellipticals and a spiral blue, Dominant and grand, each 150,000 light-years wide, But it was the overlapping pair that caught my view, Cataloged as NGC 3314, a sight I…