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…

CG4: 云球与星系

CG4: 云球与星系

ByNASA中文

2023年1月4日 CG4: The Globule and the Galaxy Image Credit & Copyright: Mike Selby & Mark Hanson Explanation: Can a gas cloud eat a galaxy? It’s not even close. The “claw” of this odd looking “creature” in the featured photo is a gas cloud known as a cometary globule. This globule, however, has ruptured. Cometary globules are typically characterized by dusty heads and elongated tails. These features cause cometary globules to have visual similarities to comets, but in reality they are very much different. Globules are frequently the birthplaces of stars, and many show very young stars in their heads. The reason for the rupture in the head of this object is not yet known. The galaxy to the left of the globule is huge, very…

M88

M88

ByNASA中文

2022年12月28日 Messier 88 Image Credit & Copyright: Adam Block, Mt. Lemmon SkyCenter, U. Arizona Explanation: Charles Messier described the 88th entry in his 18th century catalog of Nebulae and Star Clusters as a spiral nebula without stars. Of course the gorgeous M88 is now understood to be a galaxy full of stars, gas, and dust, not unlike our own Milky Way. In fact, M88 is one of the brightest galaxies in the Virgo Galaxy Cluster some 50 million light-years away. M88’s beautiful spiral arms are easy to trace in this sharp cosmic portait. The arms are lined with young blue star clusters, pink star-forming regions, and obscuring dust lanes extending from a yellowish core dominated by an older population of stars. Spiral galaxy M88 spans…

河外星系特写: NGC 6744

河外星系特写: NGC 6744

ByNASA中文

2022年11月25日 NGC 6744: Extragalactic Close-Up Image Credit: NASA, ESA, and the LEGUS team Explanation: Beautiful spiral galaxy NGC 6744 is nearly 175,000 light-years across. That’s larger than the Milky Way. It lies some 30 million light-years distant in the southern constellation Pavo, with its galactic disk tilted towards our line of sight. This Hubble close-up of the nearby island universe spans about 24,000 light-years or so across NGC 6744’s central region. The Hubble view combines visible light and ultraviolet image data. The giant galaxy’s yellowish core is dominated by the visible light from old, cool stars. Beyond the core are star-forming regions and young star clusters scattered along the inner spiral arms. NGC 6744’s young star clusters are bright at ultraviolet wavelengths, shown in blue…

M33: 三角大星系

M33: 三角大星系

ByNASA中文

2022年11月3日 M33: The Triangulum Galaxy Image Credit & Copyright: Processing – Robert Gendler Data – Hubble Legacy Archive, KPNO, NOIRLab, NSF, Aura, Amateur Sources Explanation: The small, northern constellation Triangulum harbors this magnificent face-on spiral galaxy, M33. Its popular names include the Pinwheel Galaxy or just the Triangulum Galaxy. M33 is over 50,000 light-years in diameter, third largest in the Local Group of galaxies after the Andromeda Galaxy (M31), and our own Milky Way. About 3 million light-years from the Milky Way, M33 is itself thought to be a satellite of the Andromeda Galaxy and astronomers in these two galaxies would likely have spectacular views of each other’s grand spiral star systems. As for the view from the Milky Way, this sharp image combines data…