More observing in LEO, 20 Apr 2001
Woo Hoo, three hours of good observing on Friday... bodes well for the rest of the weekend, except that I have family commitments. Happy observing everyone!
| Observer | Robert Leyland |
|---|---|
| Date | 20 April 2001 |
| Time | 2100-0000 PDT (1400-1700 UT) |
| Location | Novato CA. 38N 122.6W Elev 500' |
| Weather | 5°C Temp, 85% Humidity (4°C/95% later) |
| Seeing | LM <6.0, moderate steadiness, and excellent transparency |
| Visibility | attenuated light dome to the east, and south east. |
| Equipment | 8" F6 Dobsonian, Pentax XL eyepieces |
It had rained earlier in the day, clearing much of the dust and crud from the atmosphere, my deck was still damp. Also, some clouds to the south, and east had blocked some of the light from the major SF bay Area cities. This reduced the light domes considerably, and made the sky much darker than usual. There was a nice clear area over most of Marin county and southern Sonoma county.
The recent rain did leave the air a little unsettled, but is wasn't that bad, perhaps 7/10, with transparency a whopping 10/10. As I transcribe this report (morning after), I can see Mt Diablo very clearly off my deck in Novato, often it is visible but murky with haze and pollutants.
At around 7:30pm I put the telescope out, and began viewing in earnest around 9pm. I started with M65/66 again, which are nice and bright. NGC 3628, the third galaxy in that triple, is very nice tonight, with a split down the middle seeing is really good tonight.
A couple more checks, splitting Algieba at 85x with sharp views, and no noticeable unsteadiness. Then NGC 2903 which is nice and bright, and its little companion NGC 2916 which I haven't been able to see from home. Tonight, there it is very faintly glowing, needing averted vision to really hold.
In correspondence with Jamie Dillon (on TAC) we had talked about how hard it was to see the fourth galaxy in the NGC 3190 group. It was faint in Dick Flasck's 17.5" at Lake Sonoma a week ago, and I thought I may have seen it prior to that in my 8", but I may have been mistaken too.
This group is very easy to find by star hopping from Algieba (Gamma Leonis) move towards Adhafera (Zeta Leonis), about 2/3rds of the way there, a line of three stars intersects your path. These should be visible in your finder scope. Just on the Algieba side of this line you can find the galaxy cluster.
Right next to a relatively bright star is the circular galaxy NGC 3193, nearby is NGC 3190 which looks edge on, it is larger and just as obvious but a tad fainter. If you project a line from 3193 through 3190 and go about twice as far, you come to NGC 3185, which is a fainter oval galaxy.
I can see the circular and edge on galaxies easily at 55x, but 3185 is needs averted vision to really see its shape. At 85x and 115x it is an easy direct vision view. Returning to 3190, I get fleeting glimpses of NGC 3187 at 115x, enough to see some elongation in the same direction as 3190. It is very faint, and I spent 25-30 minutes just looking at this field to get 4 or 5 clear views. It is hard, but doable.
I took a little break to stretch, and just look up. The Beehive is easy naked eye viewing, and M35 in Gemini needs averted vision but is present. Milky way hot spots in Auriga are nice too. It is darned cold though, as the temperature has dropped to 4°C.
This seems like a good time to try to catch some of the objects I missed last time, first up is NGC 3177, which isn't very far from the 3190 group. It is faint but has an obvious nucleus that is larger and brighter than the field stars surrounding it. From my sketch it looks as though I could only see the core last time, but tonight there is a little halo visible too.
Then NGC 3226 and 3227 which are more obvious tonight, at 115x I can hold them in direct vision, with nearby NGC 3222 visible with averted vision off to the side. They do seem larger tonight as more nebulosity from the galaxy's halo is visible.
Starhopping to 51 Leo then south to NGC 3370 took a bit of work. NSOG does not have good finder charts, and 3370 is just a faint circular halo with dim field stars forming a flat triangle around it. I spotted it with averted vision, but was able to hold it with direct vision at 115x.
Then NGC 3455 and 3457 which are very faint, I star hopped to exactly the right spot and got them both in the FOV at 115x, approximately 2/3rds of the view (20') apart. There is a dim star next to the brighter object which has a visible core, but both are just little glimmers in averted vision, some moments of steadiness let me see them directly. NSOG shows another galaxy in the same field, but I can't see it at all.
The next group is by 52 Leonis, which is easy to find as it is on the line between Regulus and Nu Leo (at the top of the Lion's hind leg). This becomes my anchoring point for the next set of galaxies.
NGC 3377 is right by 52 Leo, it's really nice, an oval galaxy that fairly jumps out at you. It is large (but not Messier object large :-), with a nice bright core.
Nearby, in the same FOV at 55x, is NGC 3367, in fact it makes a nice triangle with 3377, and 52 Leo. It is not quite as bright as 3377, being diffuse and circular at 115x. NSOG mentions a double star above it, and there is also a faint pair close by.
Continuing around 52 Leo, and stepping a little further out, is NGC 3338, which is a nice diffuse galaxy, oval and possibly tilted to a 3/4 view. It points towards a bright star, with 3 adjacent field stars, two of which bracket the galaxy.
Stepping from 3338 towards 46 Leonis is NGC 3300, which was smaller than I expected and hard to spot, at 55x it was barely detectable, needing averted vision to hold in view at 115x. I tried to sketch its shape, which seemed circular, but it was so dim that I can't be sure.
When looking for NGC 3412 I kept overshooting to the M105 group, but when I did rein myself in, I found that 3412 has a nice sharply defined core, circular shape, and took magnification very well. At 115x the two adjacent bright stars were out of the FOV and the galaxy really shines.
M105 (NGC 3379) is simply awesome, with its two companion galaxies NGC 3384 and NGC 3389 all visible, it is quite a sight. At 55x, NGC 3389 is harder to see, but is much easier at 115x, as it is adjacent to a line of three field stars. M105 is very bright and NGC 3384 just moderately less so. I would guess that Messier would have included both bright galaxies together as his "non comet" object.
It's midnight and a great place to end for the night. The temperature has held steady at a cold 4°C while the humidity has climbed to 96%, causing some minimal dewing on my accessories.