First the bad weather news. My last observing outing was Sat. April 15th. New moon was Wed. the 19th. It has been cloudy since the night of the 15th, and will continue to be cloudy until the end of time, apparently. Now the good news. The early part of the lunar cycle provided me with 5 clear nights. While one of those was windy and frustrating, the others were near perfect nights! So I managed 15 hours and 45 minutes of telescope time in April. So far, 2023 is behaving not too badly. Last month I tried observing much lower in the sky than usual, and had some decent success in the southern regions of Canis Major and Puppis. Which led me to prepare a list of deep sky objects and double stars in Pyxis, taking in the region of -37 Degrees up to around -18 degrees. My latitude is 42 N, so my scope is nearly horizontal for some of these objects. Previously my lower limit for finding NGC objects was -25 degrees, but I see that on some very good nights I can push that much lower. Faint galaxies become too difficult, but the brighter ones are no problem. Same with clusters and double stars.
Uranometria Chart 171
And so I spent the early part of four nights in April searching out objects in Pyxis (a compass), with some good success. My first NGC object was tiny oc 2635, at -35 degrees. Not an eye catcher at all, just finding it and trying to see it was the challenge here. I managed to see about 8 of its faint stars, confirming my sighting the next night.
Next night I added two more NGC clusters in Pyxis to my life list. Oc 2658 sits at a slightly more comfortable -33 Degrees, my best view here was at 221x. At 10' it is considerably larger than 2635, it also has slightly brighter stars. I was able to resolve at least a dozen of them. Oc 2627 was actually a decent prize, making me glad I included Pyxis in my travels through the sky. It sits near -30 degrees. It was located at 86x, and at 120x about 15 stars are resolved. They appear to be between mag. 11 and 12, with unresolved haze in behind. 166x begins to resolve some of that haze, and my best view was at 221x. Even there, though, there is still some unresolved haze. Faint stars are popping out everywhere, somewhat like a resolving globular. A pretty fine cluster!
Uranometria Chart 153
I was observing a lot of double stars in between deep sky objects, but next up was eg 2613. Located at -25 degrees, the galaxy appeared in my 86x field of view. 120x shows the oval centre of a very elongated galaxy (6'.5 x 1'.4) at its widest and brightest. 166x and 221x give glimpses of its longer extensions. 3 very faint stars are on the south side, and a brighter one is just preceding. Though the galaxy is not a showstopper, it does reward the careful observer with its impressive size and moderate brightness.
The final two deep sky objects in Pyxis for this year were oc Ru 62, and oc Ru 157. Both are located between -19 and -20 degrees, and were in decent skies for me. They were close enough together that I could shuttle between them at low power for comparison. for 62, a tiny pair of stars north points directly to the cluster. A mag. 8.5 star sits on its preceding edge. About 15 stars can be counted here, some of them very faint. 157 is nestled amidst a group of brighter stars. At its south end is a nearly complete circle of stars. The cluster is pretty small (7'), and the stars are much fainter than the surrounding field. It has a few more stars resolved than 62.
Finally is cluster E432-3. Located at 86x. 120x shows two short intersecting lines of stars. Higher power shows a dozen stars, the brightest one about 10.5 mag. Nothing to write home about, but it is what it is, and likely seldom viewed.
Uranometria Chart 113
Turning now to Sextans (a sextant), I have been working here for several years now. In addition to trying to locate all of the NGC and IC objects, I have also amassed a large list of double stars to check out, as well as deep sky objects from other catalogues. These are mostly fainter galaxies from the UGC and MCG catalogues. My success with these latter objects is scattered, so I do focus more on the NGC.
The first decent find of the first night was eg 2156, a bright galaxy that appears very elongated at 120x (1'9 x 0'.9). I was able to see it with my 8" stop placed over the secondary mirror supports. It is pretty large and bright using 12". A 9.4 mag. star is located 2' south following, but the galaxy is still easy to see. At 221x the centre is very bright and oval, showing a fainter outer envelope. My best view was at 333x, showing a long extended nebula with a classic central dome of brightness.
Next came a a pair of galaxies, one of them a showpiece! 3165 and 3166 lie very close together in a field of view. 66 is very large and bright, seen well at 8", being oval. Full aperture at 166x shows its blazing core. The surrounding envelope is easier to view at 221x, being somewhat washed away by the central brightness. 3165 was located at 166x, being quite large itself, and also oval, but it begins to fade rapidly at 221x. Now, for added enjoyment and wonder, comes eg 3169, which can be viewed in the same field with 3166! Both can be seen at 86x using 8" of aperture. 69 has a mag. 10.8 star near the following edge. At full aperture and 120x the galaxy is bright and oval. 166x gives it a slightly less bright appearance than 66. Even so, it's still tricky trying to see the extended envelope. Views remain good all the way up to 333x. A fun area to explore!
Eg I. 600 was located at 120x, being quite large, slightly oval, and showing a bright center. Though ghostly in appearance, I enjoyed a decent view at 166x. At least compared to some of the fainter discoveries of the night.
MCG +0-27-2 represents a type of galaxy I enjoy hunting down. Very, very small, round, and at first appearing stellar. This is one time when surface brightness overrules visual magnitude. Here are the stats: 0'.4 x 0'.4: Vis. 13.8; SB 11.9. This tiny galaxy was an easy catch at 120x, though it did appear stellar. 116x and averted vision shows a pretty decent envelope, but very small. Best views were at 221x and 333x, where the galaxy is now bright, but still small. It shows a stellar core. At the very end I also observed it at 86x, as a faint and tiny star.
Eg 3243 was located at 120x, but the galaxy is somewhat dimmed by a nearby 10.5 mag. star. Viewed at 166x and 231x, it is quite large and round, showing a stellar core. Beyond the core lies a bright envelope of haze, then a fainter layer beyond that. At 333x the full size can be appreciated.
Another small but bright galaxy in Sextans is I. 651. Located easily at 120x, it appears pretty bright, and quite large (0'.8 x 0'.8). 166x, 231, and 333x all give decent views, with the round nebula exuding a pleasingly ghostly luminescence.
Coma Berenices: Uranometria Chart 91
My major spring constellation has been Coma Berenices for several years now, as I slowly and painstakingly make my way through hundreds of NGC and IC objects, mostly galaxies. This area, lying just above Virgo and immediately following Leo, is filled with some major treasures. And there are dozens of mid-bright galaxies which I won't even mention here, unless they are in the same field of view as a biggie.
One of my first conquests this year was Messier 98, or NGC 4192. Seen quite well in earlier days with the Edmund 8", the galaxy is a major sight to behold in a 12"! Though perhaps not as bright as one could wish, it certainly held my interest for a long time anyway. It's already a showpiece at 86x (even at 8"). 120x shows a tiny, bright stellar core, with elongated extensions heading out from there and going quite far. This is not an edge-on galaxy, but is tilted slightly towards us. There is a breathtaking Hubble image of this on the internet. All magnifications give fabulous views up to 333, with the size expanding with each increase. Not to be missed, even with a 6" scope! M98 points directly south towards tiny eg 4186, which is pretty faint and tiny by comparison. It shows up at the very bottom of the following image.
eg 4212 is another galaxy previously seen with the 8". Located at 86x, it is large, bright, and oval. At 120x it shows even more of its mass, also becoming quite bright and eye-catching. 166x shows its full size, with a bright centre. Worth a look.
Eg 4237 is also worth a stopover. It's a easy star hop from M 98, thanks to some nearby bright stars. This is a pretty fine galaxy, even at 86x. At 166x it becomes on obvious face on (nearly so) spiral, showing a bright stellar core. There is a bright envelope, but it fades unevenly. Best view was at 221x. A recommended stop if in the area.
There are two interesting things about eg 4222. First, this faint edge-on galaxy straddles two constellations. It's upper half is in Coma, and its lower half is in Virgo. It's pretty faint, but at higher power glimpses can be had of its full extent. Best view is 221x with averted vision, as it fades out at 333x. Secondly, just south preceding it is a real showstopper in Virgo, eg 4216. This is a breathtaking sight on a good night with a 12" scope. I had an opportunity to view it over several nights, though I did not officially log it.
A little north preceding 4222 is eg 4189, another large and bright object easily seen at 86x. At 120x the shape becomes slightly oval, and it is a bit brighter. 166x shows its full size with averted vision. Lighter and darker areas can be noted within the envelope. It begins to dim at 221x.
I'll finish up with two final bright galaxies, seen together at most magnifications. eg 4340 and eg 4350 make an outstanding pair of galaxies, with some contrasting detail to make things even more fun. Both are large and bright, and unmistakable in an 8" mirror. At 120x and 12" both show very bright cores and large envelopes. 50 seems to be a bit brighter overall. 50 becomes very elongated, and starts to resemble a mini M 31, especially at 166x. In this range 40 appears slightly oval. The envelope on that one is tricky due to the brightness of the centre.
Also worth checking out in this vicinity are 4239, 4383, and 4405.
Mapman Mike
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