M46 & M48 – wide field images

Again taking the opportunity of a half-hour imaging session, here is M46 in Puppis from the window-sill. Since it is a wide field view, the included planetary nebula, NGC 2438, (a line-of-sight effect, it isn’t in the cluster) appears pretty small, but after a bit of processing you can see it just above centre and slightly to the left. For those of you trying to see it visually, here is a quote from Stephen James O’Meara’s splendid book “The Messier Objects”:

“There is yet another illusion with M46. It appears to contain a tiny planetary nebula. NGC 2438 – – –  But the cluster and nebula are not physically associated because the cluster is 5.300 light years distant, whereas the nebula is 6,250 light years away. Positioned just a few arc minutes north of the cluster’s centre, this 11th magnitude planetary measures only about 1’ in diameter. I suspected it at 23X but 72X shows it clearly as a ghostly mote among the multitude”

(I see from my notes that I observed it visually and sketched it at 01:10 UT on 23/12/2001 with my 8″ SCT at X266)

Since there was no moon, I had another go at M48, showing a few more stars than the last one I posted.

For completeness with the Messiers in that region I have also included the recent wide-field image of M47

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