There has not been a great sky for galaxies here since April 5th. However, the upcoming early week forecast looks good. There have been a few nights with lots of haze, including the last few nights. Thursday was the full moon, and Deb and I went out on the deck to watch it rise. We also brought out some binoculars, and made a good scan of the whole of Leo, something I had not yet done. I usually focus on one small area at a time, and am prone to lose "the big picture" as a result.
On Friday night we had about 45 minutes of dark sky before moonrise. We set up our 2nd scope, the 4 1/4" Edmund Astroscan rft. Sadly the main mirror has deteriorated to the point where we will have to send it off to Edmund Scientific to be replaced. They will put in a new mirror and collimate it for around $140. We recently purchased a tripod for it, as well as a red dot finder-scope. One of the first things we looked at on Friday was M44, the Beehive Cluster. Too large to fit into the field of most telescopes, the Astroscan was made for just such a task. With the 28 mm eyepiece giving 16x, the cluster was quite impressive even in twilight. Next, we scooted around some of the brighter stars and doubles in Leo, easily splitting Gamma at 50x (18 mm eyepiece with 2x barlow). Gamma is one of the finest doubles out there, mag. 2.6 and 3.8, separated by 4" of arc, with both stars appearing golden yellow. In the 12" it looks like a pair of headlights approaching, but it is still lovely in the 4".
Last night, with about 90 minutes of dark sky before moonrise, we set up both scopes. The evening had plenty of hazy clouds. They went away for awhile, but then returned. Despite this I was able to officially log M66 and eg 3628. I have observed the Leo Triplet nearly every clear night for the past month and a half, and I have yet to tire of any of the three objects. Last night I was able to use 200x on M66 and M65, getting bright, crisp views whenever the haze would move on. It was easy to hop back and forth, even at high power. This remarkable pair of galaxies was not noticed by Messier when a comet passed through the field in 1773. According to Mechain, who did log them, the comet was probably too bright. Imagine a comet passing through this area that blotted out those two bright galaxies!
Noting the differences between the two Messier objects makes for good observational training. M65 is more elongated, not quite as bright, and has a barely visible (in the 12") dark lane down its east edge. This is more an impression than an easily observable feature, but I have seen it more than once. M66 is the brighter galaxy, slightly less elongated, and has a blazing core that lies not in the center, but just a bit to the north. This galaxy will take any magnification and still appear bright. They both fit into my 100x field, and I will continue returning to them throughout the season.
NGC eg 3628 is probably, after M31, one of the largest galaxies I have ever seen. It is viewed edge-on, and is extremely elongated. Using averted vision and 100x or 120x, it just goes on and on and on. Almost featureless in the 12", other than more brightening near the middle, it still makes a wonderful site. The darker the sky, the better this one appears, but even through haze I was able to get decent views. NB: In March 2014 I easily observed the dark lane running all across this galaxy. It was a superior observing site and a very good sky.
Two other smaller galaxies appear near the triplet, and one of them is very much worth seeking out. Immediately preceding M65 and M66 are three brighter stars in a straight N/S line. Star 73 is the one in the north, with two slightly fainter ones due south. Eg 3593 immediately precedes the middle star, and should be easily visible in an 8" scope. It is elongated E/W, and pops into view more readily than eg 3628. It is about 1/3 the size of that galaxy, but is a very enjoyable sight in the 12", its bright core easily seen. With averted vision and 100x, the full extant of the arms can be seen. If I cannot see this galaxy on a given night, then I know the sky is a bad one. Lately it is my first test for a quality galaxy sky.
A fifth galaxy is also nearby, and makes an excellent final test for good skies. Eg 3596 is the faintest of the five, lying north of the three stars just used to find eg 3693. It is south of Theta, also called star 70. This, too, is a big galaxy, oval but much harder to see than the others. If this one pops up right away at low power, I know I have an excellent night of galaxy hunting ahead. Last night it only appeared as a threshold object at medium-high powers.
I have yet to officially log these fourth and fifth galaxies, though I have sketched eg 3693. They will both be logged on the next good night. All five galaxies are an easy star hop from one another, and I now know my way around this area extremely well. If you have not visited these galaxies yet, I can highly recommend them. Telescopes of 8" or higher will offer rewarding views, especially if you go back often. In the 12", even from suburban skies, they are quite stunning and unforgettable.
Mapman Mike
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