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The Sculptor Galaxy (NGC 253)
Nearly Edge-on Spiral Galaxy
NGC 253, MCG -4-3-9, ESO 474 29, PGC 2789
Integrated Visual Magnitude: 8
Apparent Diameter: 26' x 6'
Distance: 9 Mly

Minimum requirements to view: binoculars and dark skies


This is surely one of the finest galaxies in the sky.  It was missed by Messier due to its southerly declination and awaited discovery by William Herschel's sister Caroline while hunting comets.

Part of the Sculptor group, NGC 253 lies only about four times as far as the M 31 spiral in our local group. Often photographed by amateurs and professionals alike, this galaxy reveals vast lanes of dust, which are clearly visible in the HST image below as dark brown streaks. The dust in a galaxy is often associated with the clouds of gas that stars form out of. Its effect on our view is to block the light of stars behind it and to scatter the blue starlight away, making the stars appear more red than they really are. Notice the blue clumps. Those are areas where stars have formed recently--the hottest stars are generally brighter and appear blue. They are also the most massive. The massive stars live very short lives compared to the others, so when a cluster of stars has recently formed we see the light of the many bright, blue stars. In time the blue stars will disappear. In this way the blue regions in NGC 253 trace the places where stars are actively being formed today.

NGC 253 is bright enough to be visible in binoculars from a dark site, and even the smallest of telescopes reveal a smaller version of M 31. In 8-inch or larger scopes look for a mottling, particularly on the NW side. Due to its southerly declination, NGC 253 does not rise high in the sky for northern latitudes. For this reason it is best to observe it from these latitudes as it crosses the meridian. In mid October NGC 253 crosses the local meridian at around midnight local time.

Eyepiece view in 6-inch at 50x. North is down and east is to the right.

Larger scopes (16-inch or greater) will clearly reveal the many thin lanes of dust. Their appearance around the nuclear bulge can leave the viewer with a clear impression of the apparent tilt of the galaxy. NGC 253 seen in one of these instruments is one of the most unforgettable sights in the sky.
 

Millennium Star Atlas Vol II Chart 364
Sky Atlas 2000 Chart 18
Uranometria 2000 Vol II Chart 306