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IC 2151

Proper NameName
Messier NumberNone
NGC/IC NumberIC 2151
Right Ascension5h 52m 36s
Declination-17° 47' 15"
Distancec.99,900,000 light years
c.30,600,000 parsecs
MagnitudeApparent: +13.30
Absolute: -19.83
Mean DiameterApparent: 1.2'
Actual: 49,400 light years
Hubble TypeSbc spiral
Optimum VisibilityDecember / January

A spiral galaxy in the constellation of Lepus, the Hare. IC 2151 falls almost directly westwards of the brilliant star Sirius, on an imaginary line towards Arneb, the brightest star in Lepus, though with a visual magnitude of +13.30, it is far too faint to be visible to the naked eye.

This galaxy has a distinctly spiral form, with two major spiral arms extending out from the core eastward and westward, and at least one other significant arm trailing out towards the north. While most authorities classifiy IC 2151 as a barred spiral, its bar is not distinctive, and some sources describe it as a simple spiral in form.

IC 438 (mentioned in the text below) lies southeastward of IC 2151 (which is centred in this image). To see this neighbouring galaxy in the sky, zoom this image out to a field of view of approximately thirty arcmninutes (that is, zoom out until the 'FoV' indicator in the bottom left reads approximately '30.00''. Imagery provided by Aladin sky atlas

Close to IC 2151 in the sky is another, apparently slightly larger, spiral galaxy, IC 438. The appearance of these two galaxies close together in the sky is a coincidence of their line of sight from Earth. It might be natural to assume that the apparently larger galaxy is the closer of the two, but this is not the case. In fact, the more distant IC 438 is comparatively even larger than it appears, with an actual diameter of some 100,000 light years compared to about 49,000 for IC 2151.


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