I said awhile back that 5 of every 6 non-stellar objects plotted in Uranometria 2000 are galaxies. That only includes objects to 15th mag. If we dip down to 17th or 18th mag, virtually every object past 15 is a galaxy. They are difficult to avoid if observing faint objects. Since this blog is currently concerned with the NGC catalogue (and occasionally the IC list), I will only discuss the main list at this time. With over 7800 objects of all types in the NGC list, galaxies still reign numerically supreme. It might be of interest to look at which constellations have the most NGC objects within their boundaries, and just what type those objects are. Because I live and mostly observe at latitude 42 degrees north, I will only discuss those constellations which are visible from mid-northern latitudes.
The constellation (north or south) with the most NGC objects is........Virgo! Not a huge surprise to seasoned observers, I'm sure. Virgo has 637 NGC objects. And guess what? 636 of them are galaxies! There is one lone globular cluster (gc 5634).
Number two on the list with the most NGC objects is....Ursa Major. There are 407 NGC objects. Only two are non-galaxies! There is a single very famous planetary nebula and one open cluster.
Number three constellation is Cetus. Some of it is a bit low in the sky for me, but it is all there. Cetus has 383 objects. There is one lonely and very low surface brightness planetary nebula (NGC 246). The rest are galaxies.
Number four on the list and close behind is Leo, with 378 NGC objects. Every single one is a galaxy! No relief here, though it is peppered with some lovely double stars and multiples. I am currently beginning my extensive and hopefully exhaustive exploration of this early spring constellation. It will take me many years. To date, I have located 13 of its NGC galaxies, though I've officially logged only 9 so far (it`s been pretty cloudy).
Number five is Eridanus, a constellation that winds from north to south, meaning that I cannot see all of it from my latitude. With 315 NGC objects, it has one reflection nebula and one planetary nebula. All the rest are galaxies.
So, then, the top five constellations for northern latitude viewers contain a total of 2,120 NGC objects. That`s about 2/7ths of the entire list. And a whopping 6 of those objects are non-galaxies! Let`s continue through the top ten NGC constellations.
Number six is Pegasus. With 298 NGC objects, only 3 are non-galaxies.
Number seven is Coma Berenices. 293 objects. It has 3 globulars.
Number eight is Draco. 287 objects. 2 planetary nebula.
Number nine is Pisces. 270 objects. All galaxies.
Number ten is Bootes. 267 objects. 1 globular.
We are now up to 3,535 objects, nearly half of the NGC list! All are galaxies except for 15 objects! I don't know about you folks, but I find this quite astonishing and somewhat amusing. "Well," you say, "what about those rich milky way summer constellations?" OK. Let's look at Scorpius. Lots of interesting objects there. Scorpius has a grand total of 71 NGC objects. There are some totally amazing ones, too. However, there just isn't a whole lot of them compared to those galaxy constellations (Sagittarius has 77 NGC objects).
After the top ten NGC constellations comes Hydra, Canes Venatici, Hercules, Andromeda, Aquarius, Cancer and Lynx. All are very heavy with galaxies. I am not trying to prove any point here, but merely stating some interesting (for me) facts. And no, I did not count the objects myself from the atlas. This website does it for me.
http://www.nightskyatlas.com/constellations.jsp
http://www.nightskyatlas.com/constellations.jsp
I did, however, scan through each constellation's list to search for non-galaxies, so there is some original research involved.
_________________________________________________________________________________Here are a couple of older sketches each depicting a galaxy I saw with my previous scope, the amazing Edmund 8":
My first attempt to scan some early sketches.
eg 4565, Coma Berenices. 112x.
15'.8 x 2'.1 Vis. Mag. 9.5. Sur. Br. 13.2.
One of the showpieces of the heavens.
eg 4448, Coma Berenices. 72x.
3'.9 x 1'.4 Vis. Mag. 11.2. Sur. Br. 12.9
The star field is at least as interesting
as the galaxy. The scale for this sketch
is obviously not the same as for the one
above--I cropped this one a lot.
Happy galaxy hunting!
Mapman Mike
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