Sunday, March 31, 2002

A night a La Caja de Los Gatos Observatory 3/31

Last night I had the 14.5" f/5.6 Dob set up in my backyard, to take advantage of a few hours of dark. I planned to use the Night Sky Observers Guide's selection of deep sky objects in Leo, then move on to some remaining targets on my Herschel 400-I and 400-II lists.

At dark, about 7:45 p.m., the transparency was outstanding, maybe 8 of 10, and steadiness very good, little twinkle even on Sirius. I guess temps were about 65 F. Very comfortable, I began the night in a t-shirt.

The first object was NGC2903. This is an object I use regularly when up to gauge transparency. The view at 103x (20 Nagler II) was astonishing. Obvious, large, bright, easily seen with direct vision. This had to be one of the best in-town views I've had of this object. I could easily see the small bright core, while the rest of the galaxy's thick body extended about 6'x2.5' NNE/SSW. The core was also interesting, as usually a core seems to be either stellar or just slightly fuzzy... but in this case it was clearly fuzzy and elongated along the major axis of the galaxy. NGC2903 is easy to locate, 28' S of Lambda Leonis (Alterf, SAO 80885) a nice type K5 star marking the nose of Leo and shining at mag 4.3. NGC2903 has a surface brightness (SB) of 13.6 and is about twice the size I detected.

NGC2911 shares the field with NGC2919 and NGC2914. These were very faint but identifiable. Increasing the magnification to 172x (12mm Nagler II) helped by increasing the contrast. The galaxies have surface brightnesses of 14.2, 12.8 and 13.4 respectively. I began with the pretty double star (golden and blue/purple) 6 Leonis centered in my finder. The small galaxies are framed by a distinctive pattern of stars... I saw them forming more or less a rectangle of six stars, in two pairs of three running NE/SW. The most obvious galaxy was NGC2911, just outside the line formed by the pair of stars making the SE end of the rectangle. The galaxy would swim in and out of view, and seemed to be elongated NNE/SSW. NGC2914 was fainter and located just E of the SE star in the same pair. It appeared elongated N/S. NGC2919 was the most difficult, a small roundish hazy glow with averted vision was all I could detect.

Next I moved back to NGC2903 in order to hop to its close neighbor NGC2916. This object is at the end of a chain of four stars E of GSC 1409779, which sits close and NE of NGC2903. The chain terminates when it intersects another chain of five stars (including the last star in the chain of four) running mostly N/S. NGC2916 is just beyond the intersection of the two chains and just N of a close pair of mag 12.5 stars. The galaxy appeared elongated in the same PA as the pair of stars. NGC2916 has a SB of 13.4 and is 2.5'x1.7' type Sb.

I thoroughly enjoyed the view of NGC2964. This target seems to be in the "middle of nowhere" but using Alpha Lynx, 38 Lynx and SAO 61254 (Lynx) as guides it is easy enough to move back toward the empty space above Leo's head to SAO 61633 (mag 5.9). A nice close double star sits just E of my finder star, SAO 61633, and helps determine direction. The galaxy sits at the end of a chain of stars to the NNE. It is elongated WWSW and seemed to be about 2'x1.5' in size. I could hold it with direct vision. Another galaxy, NGC2968 is visible about 6' to the other galaxy's N. When visiting these two galaxies make sure to note the gorgeous gold star that begins a chain of three pointing directly at NGC2964. Very pretty star field!

I spent some time next looking for NGC3020, 3016 and 3024. I certainly identified the field, there is a nice elongate "L" of stars (GSC 834:395, GSC 834:1197, GSC 831:505, SAO 98778) to the SW. In all, four galaxies sit in one field here, but this night they just teased me. Sometimes I thought I saw them, then I would doubt it. Ghosts playing hide and seek. I think this would be a very nice field from a dark sky. Their surface brightnesses are 13.5, 12.9 and 12.9, which makes me think conditions were beginning to deteriorate since similar SB targets were found earlier in the evening.

Next was NGC3032 - which I found much easier to observe than the 2 star rating in NSOG infers. Finding it was pretty easy too, using SAO 81004 (Epsilon Leonis) and SAO 81064 (Mu Leonis) as guides. The galaxy sits nicely framed between a pair of stars, mags 9 and 11. It has a bright core surrounded by a small round glow, making it look more like a planetary nebula than a galaxy. This object has a SB of 13.8... but the bright stellar core made if much easier to find than the SB would otherwise indicate.

The next target was NGC4133, the first object of the night on my Herschel list. Located in Draco, it is just E of the halfway point between the pointer stars in the Big Dipper and Polaris. A naked eye "teaspoon" asterism of mag 5 stars helps locate the field. The galaxy is elongated N/S and is easy to hop to from the handle of the teaspoon - SAO 7540.

It was now about 10 p.m. and conditions had changed. I put on two more layers of clothes and could still feel a damp chill in the air. Books, notes, laptop, all were feeling a bit wet, and I was finding the 20 Nagler fogging up. I kept trying but would quit after two final objects...

NGC4168 is a roundish bright galaxy set at the W end of a chain curving away to the E. I felt lucky to pick up this galaxy, it was quite dim (SB 13.2) due to increasing moisture content in the air. What was neat was the accidental view of NGC4216 one field to its E. In a darker sky, 4216 would make a great target combined with two other edge on spiral galaxies framing it (NGC4206 and NGC4222).

I finished with NGC4241 - a pair of stars sit just S of this galaxy, with an elongated triangle of dimmer stars still further S and pointing to the E. This pattern helped locate the galaxy. I had to use averted vision to pick it up, and there was no hope of finding its neighbor IC3115.

It was now 11 p.m. and I realized the moon had risen almost 40 minutes earlier, although hidden by the large oak in my neighbor's yard to the E. No wonder things were getting more difficult! I thought it was only the moisture, but add to that the brightness in the eastern sky, and it was time to pack it in for the night.

I tipped down the scope and put it to bed with its night-light. It was great to be out back again.

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