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Astronomy/Target list by size for astrophotography


I use a variety of telescopes and cameras and am looking for an extensive list of targets such as the NGC listed in order of size in arc sec. Do you have or know of one?

I still haven't found a list of objects sorted by size, but there are a number that are sorted by brightness, which in a given category tends to correlate with size. That is, if two or three galaxies have different brightnesses, then the brightest is usually the apparently largest, and the faintest is usually the apparently smallest. This sorting method only works within a category, as different kinds of objects with the same size can have very different brightnesses. For instance, a globular cluster of stars of a given size will typically be much brighter than a galaxy of the same size, because densely packed clusters have a higher surface brightness (brightness per unit of apparent area) than galaxies.

With that in mind, here are some (moderately) promising looking sites: (this has downloadable pdf lists of 7000 magnitude 14 or brighter objects, and 666 "selected" "best" objects, plus a printable sky atlas and finding charts) (A Hawaiian Astronomical Society list of various lists of deep-sky objects, with links to the individual lists; the Saguaro list of 110 "best" NGC objects looks like it might serve as a start for your interests) (A list of various objects sorted by constellation, rather than by size, but presumably the best or most interesting objects of their types in the area covered) (A brief list of the 10 best deep-sky objects in any given month, or 120 over-all).

The Atlas of the Universe site, which is mostly aimed at providing a "powers of 10" look at the structure of the Universe, has a number of subsidiary lists on its individual pages. For instance, its "within 5000 light years" page has links to pages listing bright nebulae, star clusters and the like (, while its Virgo Supercluster page (the Universe within 100 million light years, at has a list of the 200 brighest galaxies.

I realize that none of these satisfies your original desire -- a list of objects organized by size -- but I doubt that such a list exists. I also doubt that the pages listed above represent anything like a "best" collection of links that might help you with your quest; they are merely some of the more clearly presented pages from the hundred or so links I checked out to try to help you with this. I hope that they at least give you a bit of a leg up.

Finally, if you find something that is closer to what you were interested in, I'd be interested in hearing about it, in case I receive similar questions in the future.

Best wishes,


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Courtney Seligman


I can answer almost any question about astronomy and related sciences, such as physics and geology. I will not answer questions about astrology and similar pseudo-scientific rubbish.


I have been a professor of astronomy for over 40 years, and am working on an online text/encyclopedia of astronomy, and an online catalog of NGC/IC objects.

Astronomical Journal, Publications of the Astronomical Society of the Pacific (too long ago to be really relevant, but you could search for Courtney Seligman on Google Scholar)

I received a BA in astronomy and physics and a MA in astronomy, both from UCLA. I was working on my doctoral dissertation when I started teaching, and discovered that I preferred teaching to research.

Awards and Honors
(too long ago to be relevant, but Phi Beta Kappa and Sigma Xi still keep trying to get me to become a paying member)

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