狮子三重星系

狮子三重星系

ByNASA中文

2021年03月20日 The Leo Trio Image Credit & Copyright: Francis Bozon Explanation: This popular group leaps into the early evening sky around the March equinox and the northern hemisphere spring. Famous as the Leo Triplet, the three magnificent galaxies found in the prominent constellation Leo gather here in one astronomical field of view. Crowd pleasers when imaged with even modest telescopes, they can be introduced individually as NGC 3628 (right), M66 (upper left), and M65 (bottom). All three are large spiral galaxies but tend to look dissimilar, because their galactic disks are tilted at different angles to our line of sight. NGC 3628, also known as the Hamburger Galaxy, is temptingly seen edge-on, with obscuring dust lanes cutting across its puffy galactic plane. The disks of…

螺旋星系M66的哈勃影像

螺旋星系M66的哈勃影像

ByNASA中文

2021年02月24日 Spiral Galaxy M66 from Hubble Image Credit: NASA, ESA, Hubble, Janice Lee; Processing & Copyright: Leo Shatz; Text: Karen Masters Explanation: It’s always nice to get a new view of an old friend. This stunning Hubble Space Telescope image of nearby spiral galaxy M66 is just that. A spiral galaxy with a small central bar, M66 is a member of the Leo Galaxy Triplet, a group of three galaxies about 30 million light years from us. The Leo Triplet is a popular target for relatively small telescopes, in part because M66 and its galactic companions M65 and NGC 3628 all appear separated by about the angular width of a full moon. The featured image of M66 was taken by Hubble to help investigate the…

螺旋星系NGC 1350

螺旋星系NGC 1350

ByNASA中文

2021年02月12日 Spiral Galaxy NGC 1350 Image Credit & Copyright: Mike Selby, Warren Keller Explanation: This gorgeous island universe lies about 85 million light-years distant in the southern constellation Fornax. Inhabited by young blue star clusters, the tightly wound spiral arms of NGC 1350 seem to join in a circle around the galaxy’s large, bright nucleus, giving it the appearance of a cosmic eye. In fact, NGC 1350 is about 130,000 light-years across. That makes it as large or slightly larger than the Milky Way. For earth-based astronomers, NGC 1350 is seen on the outskirts of the Fornax cluster of galaxies, but its estimated distance suggests that it is not itself a cluster member. Of course, the bright spiky stars in the foreground of this telescopic…

星系M66的特写影像

星系M66的特写影像

ByNASA中文

2021年01月28日 Messier 66 Close Up Image Credit: NASA, ESA, Hubble; Processing & Copyright: Leo Shatz Explanation: Big, beautiful spiral galaxy Messier 66 lies a mere 35 million light-years away. The gorgeous island universe is about 100 thousand light-years across, similar in size to the Milky Way. This reprocessed Hubble Space Telescope close-up view spans a region about 30,000 light-years wide around the galactic core. It shows the galaxy’s disk dramatically inclined to our line-of-sight. Surrounding its bright core, the likely home of a supermassive black hole, obscuring dust lanes and young, blue star clusters sweep along spiral arms dotted with the tell-tale glow of pinksh star forming regions. Messier 66, also known as NGC 3627, is the brightest of the three galaxies in the gravitationaly…

星系NGC 5775的垂直磁场

星系NGC 5775的垂直磁场

ByNASA中文

2021年01月27日 The Vertical Magnetic Field of NGC 5775 Image Credit: NRAO, NASA, ESA, Hubble; Processing & Text: Jayanne English (U. Manitoba) Explanation: How far do magnetic fields extend up and out of spiral galaxies? For decades astronomers knew only that some spiral galaxies had magnetic fields. However, after NRAO’s Very Large Array (VLA) radio telescope (popularized in the movie Contact) was upgraded in 2011, it was unexpectedly discovered that these fields could extend vertically away from the disk by several thousand light-years. The featured image of edge-on spiral galaxy NGC 5775, observed in the CHANG-ES (Continuum Halos in Nearby Galaxies) survey, also reveals spurs of magnetic field lines that may be common in spirals. Analogous to iron filings around a bar magnet, radiation from electrons…

星系NGC 1055

星系NGC 1055

ByNASA中文

2020年12月24日 Portrait of NGC 1055 Image Credit & Copyright: Martin Pugh Explanation: Big, beautiful spiral galaxy NGC 1055 is a dominant member of a small galaxy group a mere 60 million light-years away toward the aquatically intimidating constellation Cetus. Seen edge-on, the island universe spans over 100,000 light-years, a little larger than our own Milky Way galaxy. The colorful, spiky stars decorating this cosmic portrait of NGC 1055 are in the foreground, well within the Milky Way. But the telltale pinkish star forming regions are scattered through winding dust lanes along the distant galaxy’s thin disk. With a smattering of even more distant background galaxies, the deep image also reveals a boxy halo that extends far above and below the central bluge and disk of…

星系NGC 2525的超新星

星系NGC 2525的超新星

ByNASA中文

2020年10月23日 Supernova in NGC 2525 Image Credit: NASA, ESA, A. Riess (STScI/JHU) and the SH0ES team Acknowledgment: M. Zamani (ESA/Hubble) Explanation: Big, beautiful, barred spiral galaxy NGC 2525 lies 70 million light-years from the Milky Way. It shines in Earth’s night sky within the boundaries of the southern constellation Puppis. About 60,000 light-years across, its spiral arms lined with dark dust clouds, massive blue stars, and pinkish starforming regions wind through this gorgeous Hubble Space Telescope snapshot. Spotted on the outskirts of NGC 2525 in January 2018, supernova SN 2018gv is the brightest star in the frame at the lower left. In time-lapse, a year long series of Hubble observations followed the stellar explosion, the nuclear detonation of a white dwarf star triggered by accreting…

哈勃影像：邻近的螺旋星系NGC 5643

哈勃影像：邻近的螺旋星系NGC 5643

ByNASA中文

2020年10月5日 NGC 5643: Nearby Spiral Galaxy from Hubble Image Credit: ESA/Hubble & NASA, A. Riess et al.; Acknowledgement: Mahdi Zamani Explanation: What’s happening at the center of spiral galaxy NGC 5643? A swirling disk of stars and gas, NGC 5643’s appearance is dominated by blue spiral arms and brown dust, as shown in the featured image taken by the Hubble Space Telescope. The core of this active galaxy glows brightly in radio waves and X-rays where twin jets have been found. An unusual central glow makes NGC 5643 one of the closest examples of the Seyfert class of galaxies, where vast amounts of glowing gas are thought to be falling into a central massive black hole. NGC 5643, is a relatively close 55 million light…

拉直后的星系M51

拉直后的星系M51

ByNASA中文

2020年8月21日 Unwinding M51 Image Credit & Copyright: Data – Hubble Heritage Project, Unwinding – Paul Howell Explanation: The arms of a grand design spiral galaxy 60,000 light-years across are unwound in this digital transformation of the magnificent 2005 Hubble Space Telescope portrait of M51. In fact, M51 is one of the original spiral nebulae, its winding arms described by a mathematical curve known as a logarithmic spiral, a spiral whose separation grows in a geometric way with increasing distance from the center. Applying logarithms to shift the pixel coordinates in the Hubble image relative to the center of M51 maps the galaxy’s spiral arms into diagonal straight lines. The transformed image dramatically shows the arms themselves are traced by star formation, lined with pinkish starforming…

棒旋星系NGC 1300

棒旋星系NGC 1300

ByNASA中文

2020 June 11 Barred Spiral Galaxy NGC 1300 Image Credit: Hubble Heritage Team, ESA, NASA Explanation: Big, beautiful, barred spiral galaxy NGC 1300 lies some 70 million light-years away on the banks of the constellation Eridanus. This Hubble Space Telescope composite view of the gorgeous island universe is one of the largest Hubble images ever made of a complete galaxy. NGC 1300 spans over 100,000 light-years and the Hubble image reveals striking details of the galaxy’s dominant central bar and majestic spiral arms. In fact, on close inspection the nucleus of this classic barred spiral itself shows a remarkable region of spiral structure about 3,000 light-years across. Like other spiral galaxies, including our own Milky Way, NGC 1300 is thought to have a supermassive central…