by Albert Highe
The virtues of a small scope are apparent on a night like Wednesday. It was almost 9PM when I realized that I felt a bit low and wanted to get out of the house. Five minutes later, my 6" f/6 portable dob was loaded up and I was on my way to Montebello.
At 9PM the sky over Redwood City was already murky and the temperature was 66ºF. Yet, I had a nice night at MB on Monday, and James T. raved about the conditions on Tuesday. I hoped that the inversion layer would persist tonight as well.
As I drove up Page Mill Road, the temperature hit a low of 62ºF. As I climbed higher, the temperature began to rise. I smiled. By the time I hit the parking lot at 9:35PM, the sky was clear and the temperature was reading 75ºF. I stepped out of the van to find warm, dry, clear conditions with no wind and four other observers already enjoying the night.
Another virtue of the small dob is that it sets up in 30 seconds. Within a couple of minutes I was unpacked and observing high power, crystal clear and sharp views of the Moon. I can't remember ever seeing the Moon so well. Seeing was great.
I didn't have an observing program. After viewing the Moon, I just started poking around the sky. Even with the Moon's illumination, objects looked quite good. Throughout the night I used 8-24mm zoom and 4mm and 10mm Lanthanum eyepieces.
The 6" uses only a lightweight 1X red dot finder. This is plenty for finding most Messier objects where I can see stars or bright planets. For star hopping, I used the zoom on its widest setting and then would select the magnification for the most pleasing view
Although seeing was very good, I couldn't split Antares. It was down in the murk and twinkling a bit. However, the double-double nu-Scorpii is nearby and just slightly higher. I could split both components at 228X. I could resolve the Airy disks of the closer, brighter pair about 50% of the time.
Even with the Moon still up, the showpiece objects in Sagittarius were rewarding. M22 was a ball of stars (although much fainter and less numerous than in my 17.5" scope). The shape of M17, the Swan Nebula, was unmistakable, although the very faint extended nebulosity was missing. The "wings" or "check mark" shape showed up very well without filters and I could also detect some of the dust lanes within the body. In M20, the Triffid Nebula, I could see the three prominent dust lanes in the southern, brighter portion, and detect the very faint northern section. My favorite view in this area was M8, the Lagoon Nebula. The 6" offers a much wider f.o.v. than my larger scopes. I had forgotten how interesting the view of the Lagoon Nebula is within the context of its companion open cluster and surrounding stars. In some respects, I enjoyed this view more than in my larger scopes. Although some of the finer detail is missing, I could easily see the brighter knots and the broad dark dust lane separating the brighter part of the nebula from the open cluster.
I remembered to visit one of my favorite globular clusters that I discovered last year - NGC7623. It is in southern Sagittarius, just over the border from Corona Australis. It is quite bright. Unfortunately, it was too low in the haze to see individual stars.
I also took a quick peek at one of my favorite object pairs: B86, the dark nebula known as the Ink Spot, and the open cluster NGC6520. The Ink Spot was washed out. If I hadn't known it was there, I probably wouldn't have seen it.
James T. wandered over and pointed out his last know position of comet C/2002 O4 (Hoenig) and its direction of motion. With that information I scanned at low power to find it. It was rather dim with the Moon still out. But zooming in improved contrast. It still didn't show a tail, and looked like many faint face-on galaxies. Later, after the Moon set, contrast was better and it appeared larger and brighter. I also thought I could detect a somewhat brighter central area.
James also mentioned the carbon star, mu Cephei. His chart also identified it as Herschel's Garnet Star, apparently quite famous. I had never seen it, so we hopped over to have a look. It was very bright, but disappointing. At best, I'd say it was burnt yellow, a far cry from red. This reminded me of T Lyrae, a very red star I had first seen at Montebello earlier this summer through my 17.5". Although much fainter than mu Cephei, T Lyrae was definitely a red star, its color still obvious with the 6". To be fair, these carbon stars are all variables and are their reddest at minimum. I'll continue to monitor mu Cephei to see if I can catch it in a redder state.
As the Moon set, the fog apparently was settling into the valley. The light dome to the SE was gone and the light dome to the NE had diminished. The Milky Way was bright with distinct dark lanes. Conditions certainly didn't compare to true dark sites, but it was the best I have ever seen at Montebello.
M31, M32, and M110 were all easy to see in the NE at various magnifications. I could even detect the major dust lane in M31.
With the darker skies, I thought of more challenging objects and NGC7331 came to mind. It was a quick hop from eta Pegasi and easy to locate at low power. Higher magnification provided a good view of the bright, elongated core and fainter thin extensions. Pushing my luck, I scanned for the swarm of very faint galaxies, including Stephan's Quintet, that populate this area. Alas, they were outside the capability of the scope and/or sky conditions.
I then did a quick survey of the double star eta Cassiopeiae, the Double Cluster in Perseus, and M13 in Hercules. I've been viewing M13 a lot lately with my 17.5". Yet, the view is still magic in the small scope. It clearly is a large globular cluster with dozens of resolvable stars.
The only object on my list for tonight was Uranus. I had looked up its position in "The Sky" software. It was just on the Aquarius/Capricornus border. Using the SA2000 star charts, I was able to hop to it rather quickly. At 90X, I could just detect that it wasn't stellar, although the green color gave it away. At 229X, it was a nice small greenish disk.
I remembered that I haven't seen M11, the Wild Duck Cluster, in years, and probably never through my 6" scope. To locate this object, I turned to my favorite pocket atlas, "The Observer's Sky Atlas" by E. Karkoschka, page E19. I followed bright, more familiar star patterns from Hercules, through Ophiuchus and Serpens, down into Scutum. M11 is a wonderful object in a 6" scope. Dozens of stars are visible, strewn about in a rough triangular pattern. I studied the more regular triangular tip that gives this cluster its name. Yes, I could see the resemblance to the pattern birds adopt when migrating. But, as I was reflecting on this, Bob J. relayed his story of the 11 year old girl who had identified it as an angelfish. And instantly, the angelfish popped into view. Although the triangular tip resembles a flock of birds, the rest of the flock is quite disorganized. On the other hand, these formally disorganized stars neatly follow the outlines of an angelfish. I will never call M11 anything else.
I then revisited all the other objects listed on page E19. M29 is a small open cluster that appears at first as a faint patch, but reveals a few resolvable stars at higher power. NGC6712 in Scutum is a small, faint globular cluster with no resolvable stars. IC4756 in Serpens is a large, sparse open cluster that requires my widest field. NGC6633 in Ophiuchus is fairly large, about half the size of above, with moderately bright, scattered stars. NGC6572 was a pleasant surprise. It's a very bright, small planetary nebula. It required at least 100X to identify it as non-stellar. Most surprising is that its green color was apparent in the 6".
While hoping through this area, I also came across two other faint patches not plotted on page E19. SA2000 identified them as open clusters NGC6682 and NGC6683. Each appeared nebulous at low power but revealed a few individual stars at moderate power.
While moving over to another favorite, M57, The Ring Nebula, I stopped to view the double-double, epsilon Lyrae. All four components were an easy split with lots of black space between them. The Ring Nebula was a bright smoke ring.
I finished the night with M27, the Dumbbell Nebula, in Vulpecula. Can we have an 11 year old come up with a better name than Dumbbell for this wonderful object? I had a life-altering view of M27 with my 17.5" scope from dark skies a week ago. Yet, the view in the 6" still fascinated me. It is very large and bright. Initially, one does see the scalloped shape that resembles an apple core. With averted vision, I detect the larger, fainter, elongated oval structure.
At 1:30AM I packed up and appreciated another benefit of my 6" scope. It was in the car within 30 seconds. It took longer to put away my eyepieces. But within five minutes I was saying my good-byes and starting up the van. My thermometer showed a whopping 78ºF! As I drove down the hill I witnessed what James had mentioned the night before. There were no valley lights. A blanket of fog covered them. As I descended into the fog, the temperature dropped to 59ºF. Although the van's thermometer may be off, I do believe the Delta T.
As I was driving home, I reflected on my mood and on the objects I had observed tonight. I had left the house feeling down and was returning rejuvenated and excited. In one night I had seen a broad spectrum of interesting objects spanning light seconds to 40 million light years: our Moon, a passing comet, a distant planet, red carbon stars, double and multiple stars, open and globular star clusters, dark and bright diffuse nebulae, planetary nebulae, and galaxies.
It doesn't always take large, expensive equipment and distant trips to enjoy this hobby.