The Silver Greenback or Sculptor Galaxy is the brightest deep-sky object within the diminutive constellation Sculptor. NGC 253 is extremely inclined at 78° from face-on, and doesn’t have distinct arms throughout its broad, 27.5′ by 6.8′ disk. Latest imaging reveals a poorly developed bar and two concentrated arms amidst a disk wealthy in darkish and emission nebulae.
At eighth magnitude, NGC 253 could be seen in binoculars and is about 7° south of Beta (β) Ceti. Barely bigger optics might mean you can notice the small nuclear brightening, and even bigger apertures will reveal some granulation from the abundance of dust clouds. With out distinctive arms, the mottled disk is worthy of scrutiny.
NGC 253 is positioned 11 million light-years from us and is the biggest within the Sculptor Galaxy Group, one of many closest galaxy teams to ours. It’s so shut that different members are scattered in different constellations, together with NGC 247 in Cetus and NGC 625 in Phoenix. This group is dominated by low-mass irregular galaxies just like the Massive and Small Magellanic Clouds; its members are greatest seen in massive optics as a result of they vary from tenth to sixteenth magnitude.
The Silver Greenback Galaxy is about as removed from the aircraft of the Milky Way as attainable, positioned round 2° from the South Galactic Pole. Meaning we’re trying by way of a minimal quantity of interstellar dust. The closest brilliant deep-sky object (1.8° southeast) is the magnitude 8 globular cluster NGC 288. It’s value noting that though most globulars are near the Milky Way’s galactic aircraft, at 37′ northeast of the South Galactic Pole, NGC 288 is about so far as a globular cluster can get in obvious place (however not bodily distance) from the aircraft.
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