Wednesday the 9th of December, several local San Francisco bay area observers met at the Mid-Peninsula Regional Open Space District's Montebello site for a clear but cold observing session. With frost thickly layering the back deck at my home (a thousand feet or so lower than Montebello) each of the past four mornings, I came prepared for what a Californian would consider Siberian conditions. Fortunately, the chill was not as intense as the prior nights, and other than unusually bright skies for the site, and some high clouds moving in from the north after 10 p.m., it was wonderful to get out, see some new and familiar faces, and spend some time looking through a telescope.
I brought my 10" f/5.6 home-made Dob "Pliskin" (I like it, Dave) to start a list that seemed appropriate from a brighter sky location with a smaller scope (after all, I regularly share observing sites with Jay Freeman, a master of small aperture object detection).
As usual, there is a lot of catching up with friends that goes on, and after about 40 minutes talking about people moving, selling homes, observing from different parts of the country, my eyes were acclimated and I got down to business. I had printed the November Herschel 400 objects off TAC's web-site (http://www.seds.org/TAC) listed under "Observing - what to view". Somehow, my list printed oddly, so I am sure I missed some objects.
The first item was an old familiar one, NGC205, aka M110. While substantially dimmer than M31 and M32, it was easy to view. I could also tell from the diminished brightness of M31, that the sky was indeed rather poor and I would be "working" to detect some of the dimmer objects on the list.
I next moved to NGC404, another good object for calibrating sky conditions. Being located in the same 72X field of view as Beta Andromeda (Mirach), this has to be one of the easiest objects (short of the moon, sun, Jupiter or Saturn) to locate. Can you think of any other super-easy targets (maybe the Ring Nebula) to point a newbie at? Anyway, NGC404 was smallish, after viewing NGC205, but still, reasonably bright and larger than many other Herschel's I have viewed. It is a round galaxy, looking kind of like a smaller, bright Crab Nebula.
Next up was NGC752. My 19 Panoptic was no match for this object, a very large open cluster with many bright stars. I suspect the cluster would make a good binocular object. I could tell I was on the object by sweeping across it and seeing how dramatically the star population dropped off. In fact, this area, just between the wide end of Triangulum and the sweep of Andromeda, is much more a galaxy rich hunting ground than it is a place to find object (or than field stars) in our own Milky Way. For example, just off NGC752, I was searching out NGC688 (mag 13 galaxy in a very rich cluster) from the Sierra Nevada high country last summer.
About this time, two TACies that I had not met before came over and noted I had a Dob. I am terrible with names, and I apologize to them if they're reading, but I don't remember who you are (but I'd know your voice in a flash). One of them asked if he could point my scope at something. Well, I get in plenty of observing, so what the heck, go ahead. Now, I really, really don't mind, because I do observe so much, and I have already seen these Herschel objects while working the entire list in larger aperture, but... after an hour or so, the two newbies left my telescope and began looking at and through the other nice selection of scopes, that included a Ceravollo HD215 (I hope that's right, Peter), a brand new 6" AP, 7" Starmaster Classic, 14x70 binos mounted on a tripod, 3.5" Questar, a 10" Meade reflector on an equatorial mount, 8" Celestron SCT, and probably one or two others. All in all a nice turnout, and plenty for first-timers to a TAC observing session to enjoy themselves with.
Back on track now, my next target was NGC772. This one is also situated in an easy location for Telrad users, being off mag 2.7 Sheratan (Beta-Arietis) and mag 4.8 Mesarthim (Gamma-Arietis). Easy jump from there to this roundish object. The Sky lists it at mag 10.30, my list software shows over mag 11.5. Strange. Anyway, it did appear round and have a bright core. Not difficult at all to view.
Now for the "fun" (being facetious) stuff. Small open clusters buried in the Milky Way. Oh joy. Every grouping of stars in the Milky Way looks like a cluster. Maybe these "clusters" are just "made-up" to drive amateurs batty. Well, I did find the first one, I think. NGC129 in Cassiopeia. Not difficult to find, sitting mid-way between and slightly out from the line described by mag 2.8 Navi (Gamma-Cassiopeiae - center star in the "W") and mag 2.4 Caph (Beta-Cassiopeiae). The reason I have problems with these sort of objects is there is no way to know what the star field really looks like unless you use a computer in the field. Well, I usually do, but last night, although I had it, I did not "power up"... choosing to work for my successes using the Tirion SkyAtlas 2000. The charts are good, but the computer makes print charts seem archaic.
I tried next to locate NGC136, which on the chart is right next to NGC129. I thought I found it, a dim haze, but I now think I missed it. The computer is also very good at giving object sizes, which the print chart did not. If I was thinking, I'd have use my SkyAtlas 2000 Companion. In it, this object is nicely described as 1.2 minutes in size (I was looking for something much larger), and "20 stars; detached, weak concentration of stars toward center; moderate range in brightness; poor, very faint, small cluster; dist = 14.3KLY; br*=13.0p". Such info is invaluable when searching.
Enough work on open clusters... they can be more frustrating than a stellar mag 15 galaxy.
Moving to the south, I began trekking around in Cetus. NGC615 was fun and easy. I used a line from mag 3.6 Eta-Ceti to mag 3.8 Theta-Ceti and beyond until my eyepiece view showed mag 5.9 SAO129371. The chart showed four galaxies around this star - NGC615, NGC636, NGC596 and NGC584. All were identifiable, two pair on each side of the star. I found 596 difficult, and that surprised me as the three of the objects are Herschel 400 targets, with the easier galaxy NGC636 not being on the list. Must be a surface brightness thing. If you get a chance to look at these, you should.... it is fun to see this little galaxies in line with the bright star.
Nearly between the mag 3.9 star Baten Kaitos (what a name! Or... Zeta-Ceti) and mag 3.6 Tau-Ceti, sits NGC720. My notes say this galaxy has a bright core and appeared to both Leonard Tramiel me that it might be barred. My list program says its magnitude is between 11.5 and 12, while The Sky calls it mag 10.19, elongated, with a bright core. I guess the elongation stood out as a possible bar. I'd sure be interested in knowing how one listing can be over 1.5 mag different in brightness than another!
My last object in Cetus for the night was NGC779. This one would prove a bit trickier to star hop to, as at first it appeared to be in an area with few decent landmarks. I had to study the surrounding area before I came up with a plan. I can see how the person who defined Cetus' shape drew in the lines. I would reach NGC779 by using two pair of stars as markers. Both pair are in the "back" of the whale. I began at what many people recognize as the "bend" in the tail, near M77. Those stars (three) are mag 2.9 Menkar (Alpha-Ceti), mag 3.6 Kaffajidhma (Gamma-Ceti) and mag 4.0 Delta-Ceti. From there, looking west, I could see a faint line of four stars that end at a brighter pair. The four stars are mag dim Mira (Omicron-Ceti), mag 5.9 SAO129665, mag 5.5 SAO129490 and mag 5.9 SAO129371.
Beyond those were the two bright stars Theta-Eta and Eta-Ceti. Now, below the first two SAOs I mention, is a mag 5.7 star SAO129624. With these three forming a recognizable triangle, it is easy to drop on NGC779. A lot of work, but the galaxy is quite nice, bright (but dimmer than NGC720) and obviously elongated.
The night was wearing on. It was getting chilly. My toes, regardless of neoprene socks with liners and Sorrels, were feeling like they belonged in the grocery store meat counter. But, it was not yet even 10 p.m.
I next hunted down NGC651 in Perseus. This was fun, since I had to come off the stars in Andromeda to get there, and the constellation was dead overhead. Neck strain, turning in circles until I looked like a drunk (no, no Mexican Coffees last night) about to topple. What a sight I must have been (glad it was dark!). I used mag 3.1 Beta-Trianguli to draw a line to and through mag 2.3 Almach (Gamma-Andromedae) to mag 4.2 Phi-Persei. Just under a degree further on that line and... surprise! The Little Dumbell - M76. It is fun when you don't look at the Messier numbers ahead of time and land on something obviously outstanding. M76 easily showed a bi-lobed structure, was quite bright and for a planetary, relatively large.
I now moved south, down to darker skies, into Pisces. NCG488 would appear to be as challenging to locate as NGC779 was, until I realized it had the same solution. A series of stars defining the constellation's line, which were just identifiable naked-eye. Soon, jumping from mag 4.3 Alrescha (Alpha-Piscium) to mag 4.8 SAO110206, then mag 4.7 Nu-Piscium, mag 5.1 Mu-Piscium. A quick turn south and I could see mag 5.3 89-Piscium. The galaxy lay just between Mu and 89. Not bad! My notes indicate a fairly bright galaxy with a single notably bright star in the field. The Field Guide says the galaxy has many arms, so I'll have to visit this one again in darker skies... it is also 100M-LY distant, which I find simply mind-boggling....
My last target for the night in Pisces was NGC524. This was just a short jump back up above Mu-Piscium, and easy to land on. My notes say it was easy to see, bright, probably face on, and I wondered if I was seeing other galaxies in the field. Only NGC524 shown on the Tirion 2000. Now that I look at The Sky on my PC, I can see I was detecting other galaxies, as this is a very rich galaxy cluster. What scares me though is, other than nearby NGC489 at mag 13.0, the other perhaps dozen galaxies are all mag 14 or dimmer. Probably floaters, right? ;-)
The last two objects for the night were NGC252 and NGC288. I won't go into 253 much, as it is a showpiece object that is probably written about extensively. Let's put it this way, if you haven't seen it, get your telescope out asap and look. It is big, bright, has lots of dust and HII regions. It's a killer galaxy. NGC288 I had seen before, but it never ceases to amaze me how large it is for its dim appearance. It must be at least 15 minutes in diameter (okay, The Sky says 13.8 minutes... close), and is highly resolved, but all the stars are dim. I wonder if this is just extinction due to its low altitude for us northern observers. Anyone still reading this from down under? I know you have Omega and 47 Tucane, but, what does 288 look like to you?
With my toes finally getting really uncomfortable, my fingertips beginning to feel like frozen toes, and the thought of black ice forming on the mountain road if I stayed later, I packed up, poured a cup of full strength and returned to the land of bright skies. I plan to come back to Montebello with my 10" Dob, and continue the bright Herschels. It is fun to start over, when the entertainment is good. Hopefully the weekend will be clear, and I'll get to some really decent skies...
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