241201 - NGC1398 Unnamed galaxy in Fornax
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click image to enlarge
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ASTRO:
type=Grand Spiral Galaxy const=Fornax mag=10.4 dist=65 M ly size=~135 k ly IMAGE: location=EB Driveway BrtlCls=4 exposure=CMOS OSC: 144x180s (7.2h) EQUIPMENT: camera=ZWO ASI2600MC-Pro optics=Explore Scientific ED102 CF triplet APO refractor corrector=1.73x Baader Hyperion 24mm EP (proj. mode), FL(eff.)=1238mm, f/12.1 filter=Optolong L-Pro LPS mount=Celestron AVX EQ guiding=Orion 60x240mm, ZWO ASI224MC SOFTWARE: acquisition=Stellarium, APT, PHD2 processing=PixInsight (RCAstro), Photoshop (APF-R) (Lumenzia), LrC |
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Why do some spiral galaxies have a ring around the center? Galaxy NGC 1398 not only has a ring of gas and dust containing pearly stars around its center, but a bar of stars and gas across its center, and spiral arms that appear like ribbons farther out. The featured deep sky image shows this Grand Design spiral galaxy as it lies about 65 million light years distant, meaning the light we see today left this galaxy when dinosaurs were disappearing from the Earth. This photogenic galaxy is visible with a small telescope toward the constellation of the Furnace (Fornax).
NGC 1398 is an isolated galaxy, meaning it is separate and distinct (not "grouped" together with any other galaxies). It is not inside our solar system or the Milky Way. It exhibits a double ring structure with the ring near the center likely being an expanding density wave of star formation, caused either by a gravitational encounter with another galaxy, or by the galaxy's own gravitational asymmetry. The galaxy has a diameter of appx 135,000 light years and is estimated to contain over 100 billion stars making it comparable to our home Milky Way. It was first discovered by German astronomer Friedrich Winnecke on December 17, 1868, while he was searching for comets.
Nebulae can be seen dotting the spiral arms of the galaxy. The spiral arms are wound up so tightly that at first glance they look like rings. For a while in fact, astronomers weren't sure just what the structure of this galaxy was; some said the inner arms formed a ring, some said it's not really a ring but that the outer arms form a ring-like structure (called a pseudo-ring).
Galaxies are immense structures, and immensely complex, too. They are like old friends to astronomers who have observed them for a long time; but they still constantly surprise us. Using a bigger telescope to investigate them is important; but, perhaps even more important is using a telescope outfitted with photographic equipment that sees other light than what our eyes can see. Only then do the different features stand out, so that advanced astronomers can study them and figure out what's what. For example, see Mark Hanson's NASA APOD image of NGC1398 captured from Observatorio El Sauce in Chile.
NGC 1398 is an isolated galaxy, meaning it is separate and distinct (not "grouped" together with any other galaxies). It is not inside our solar system or the Milky Way. It exhibits a double ring structure with the ring near the center likely being an expanding density wave of star formation, caused either by a gravitational encounter with another galaxy, or by the galaxy's own gravitational asymmetry. The galaxy has a diameter of appx 135,000 light years and is estimated to contain over 100 billion stars making it comparable to our home Milky Way. It was first discovered by German astronomer Friedrich Winnecke on December 17, 1868, while he was searching for comets.
Nebulae can be seen dotting the spiral arms of the galaxy. The spiral arms are wound up so tightly that at first glance they look like rings. For a while in fact, astronomers weren't sure just what the structure of this galaxy was; some said the inner arms formed a ring, some said it's not really a ring but that the outer arms form a ring-like structure (called a pseudo-ring).
Galaxies are immense structures, and immensely complex, too. They are like old friends to astronomers who have observed them for a long time; but they still constantly surprise us. Using a bigger telescope to investigate them is important; but, perhaps even more important is using a telescope outfitted with photographic equipment that sees other light than what our eyes can see. Only then do the different features stand out, so that advanced astronomers can study them and figure out what's what. For example, see Mark Hanson's NASA APOD image of NGC1398 captured from Observatorio El Sauce in Chile.