Tuesday, March 1, 2005

Stalking The Bear

Clouds hung dark over the eastern hills south of San Jose as I drove toward Henry Coe State Park, Saturday afternoon, the 1st of March. It sure looked like winter, and all I could do was hope that the weather forecast for mostly clear skies would prove correct. So, I pressed on, enjoying rare light traffic on 101 south through the construction zone. Breezes out of the west greeted me in Morgan Hill, as I turned up East Dunne Road for the final part of the drive.

Climbing the hills and passing Anderson Reservoir, over the bridge and along the shore, begins my favorite part of the drive. Here is where I leave behind the city and am greeted by nature's changing seasons. The hills are now green, and the wildflowers are not far behind. Old gnarled oaks branch contortedly reach toward the sky on the uphill side of the road. Passing Jackson Ranch, the climb begins, with views of the south county valley, San Jose, the Diablo Mountain Range toward Mount Hamilton and south to Pacheco Peak, and the Santa Cruz Mountains to the west. Each turn is a scenic treat, cleansing the mind and spirit.

The view from Coe's overflow parking lot, where local amateur astronomers meet on 3rd quarter and new moon weekends, is the a wonder. The horizons are unparalleled among bay area observing sites... an unobstructed 360 degree panorama, save for the single oak at the south end of the lot. This observing site offers the best combination of area and elevation... 2600 feet high and large enough for perhaps 40 telescope and vehicles. When the fog is in, it is as dark as any site within an hour of the south bay. It offers easy access... no gate combinations needed, no need to leave during the night, or to arrive before dark. A friend joking said last night "we have to get Mark to like Fremont Peak again".... but why? I know others are happy there, but to me it does not compare either in set up area (for a group) or ease of access. Likewise with Dinosaur Point... since gatekeepers have become a necessity, I find it significantly less appealing... even though the drive there is easy, it has great horizons, paved surface and is darker on average than other local spots. Yes... I am sold on Coe.

Sunset came with a clear sky. Golden and red tones over the western hills. The scene was idyllic. By now there were maybe ten of us set up, mostly long time TACos along the eastern edge of the lot. A few newcomers were there too. A nice 7" TMB marked the northern end of the scopes, a 6" AP and Tele Vue Genesis to the south. My 18" f/4.5 Obsession was probably the largest aperture there, but other reflectors included a 10" Starsplitter, C11, M210(?) Takahashi Dall-Kirkham, and assorted other setups that arrived after dark, that I did not see. By the time people stopped trickling in, we had 18 or 20 telescopes set up.

One observer stopped by and showed a few of us his sketches of the Herschell 400-II. What a magnificent job... worthy of publication. A binder thick with visual impressions. I was extremely impressed. This is a hint at what type of projects observers, albeit the more serious of them, are involved. in.

I was continuing a long term project too. I had under 400 targets left on my until recently, stalled program of observing all the 2500+ Herschel objects. What I had left were the spring targets, the ones that suffer most from inclement weather. Tonight, I began low in the northeast as the Big Bear poked its nose up. I had the dimmest forty four Herschels in Ursa Major remaining.

As darkness overtook us, it was time to stalk the bear.

I certainly don't want to describe forty four objects, but the night was successful. I finished the list in Ursa, finding many of the object either visually interesting, or quite challenging.

But before I mention some of the highlight objects, another observer brought over a binoviewer made by Denkmeier (?) and was interested in what it would do in larger aperture. The binoviewer was equipped such that it did not require any modification to my Dob, and only magnified 1.2X. We used it on M42, NGC 2903, M81 and M82, and a few other objects. I thought these were fantastic, being that they worked without any mods to my scope. The views of M42 (with a pair of 19 Panoptics) showed all six stars in the Trapezium very easily. It was a highly detailed and relaxing view. What I did note though was what I already knew about binoviewers - there is a significant reduction in light throughput. The big bright stuff is *great* ... but there is NO way these would be effective for hunting the dimmest bits of fluff - stuff I was after last night in the Bear.

NGC 4511 is an example of the scenery getting there being better than the destination. A long string of bright stars run north to south due east of this dim galaxy. Nice to see... but there is also a wonderful pair of parallel curved star chains extending west from the midpoint of the bright string.... ending with the galaxy cupped, centered, just outside the end pair of stars in the chains. Distinctive star patterns are both visually pleasing and very useful in locating dim targets. NGC 4511 is a mag 14.77 irregular galaxy.

NGC 2820a was one of those targets that just seemed to be exactly where I wasn't looking. I could not believe the difficulty I had locating it! It is really in an easy spot, but sometimes the old hand/eye/brain thing just seems to snooze. But I finally did find it, and with my 7 Nagler at 280X I was able to obtain a very pleasing view of three galaxies in all within 6' of each other. NGC 2820 is a large highly elongated galaxy (4.1'x0.5') at mag 13. Nearby is NGC 2814, west of 2820, at mag 14.3 and elongated N/S 1.2'x0.3'. Although it is not marked as NGC 2820a, I believe IC 2458 is it. This was so fun to see, as it is a little pinch of amazing creation sitting not even 8" off the SW tip of the 2820. NGC 2820a is a mere 0.5'x0.2' in size, shimmering at a ghostly mag 15.5.

The next one I'll mention is NGC 3552, which apears to be part of Abell 1185. This was simply a pleasing view. A chain of six galaxies running predominantly north to south, ranging in magnitude from 13.9 to 15.6, with a pair of close galaxies just 6' to their east (and some dimmer ones around those).

About this time another observer came by and asked to check NGC 2261 on my computer. She was having some difficulty finding it using printed charts. What fun! This is Hubble's Variable Nebula, an object I hadn't looked at in years. I swung my 18" around and soon had what we used to call "Richard's Comet" in the field of view. Darn, if it doesn't look like a stubby comet! This is a target to check out this time of year.

But, back to the Bear.

Doing a Messier survey? Bored with M40? NGC 4362 is in the same widefield view. So are NGCs 4364 and 4358... forming a tight threesome with 4362. NGC 4358 weighs in at mag 16.4... requiring my 7 Nagler to tease out. Bracketing these three diminutive specks of galaxy are two other larger ones, roughly to the east and west - UGC 7534 and NGC 4335. This is a fun group, and easy to find off the "famous" Messier. BTW... there are other galaxies closer to M40, my target last night was NGC 4362.

Another nice but dim group is NGC 4967, 4974 and 4973. These range in magnitude from 15.0 to 15.5. If the night is good enough you can perhaps ten galaxies in this location, all within about a 1/3 degree field of view. I think this area was my favorite of the night.

For sheer star hopping "pretty" stuff, I enjoyed finding NGC 5294. Two bright stars are part of a quasi-chain running east to west, with several double and triple stars curving to the south the west, leading to the little galaxy. NGC 5294 is listed at mag 15.29.

Maybe someone can tell me what NGC 2810B is. I don't know! I sure found NGC 2810 - bright at mag 13.1 and 2810B seems to share its RA and Dec, but there is no sign of anything else there. A mystery.

NGCs 4547 and 4549 are interesting. A question mark asterism of stars is to the west of this pair. To the east of the top of the question mark is a bright star I used to mark the distance out to the galaxies. At 280X both galaxies were visible as shadowy glows, at mag 15.9 and 16.5. MCG 10-18-71 seemed almost bright nearby to their northeast, at mag 16.2.

The last object I'll report on was NGC 3930a, and finished my Herschel list for Ursa Major. NGC 3930 is an interesting object due to its low surface brightness. It is fairly large, especially at 280X. But what is 3930a? I looked for a while and eventually concluded I could see some spiral arms structure, and that there seemed to be a star involved. But then, after more inspection, I felt I was detecting an HII region glowing to the west of the core, in a spiral arm. Could this be the "a" in 3930a?

I felt great. It must have been 3:30 a.m., but I was not tired. In fact, it had been some time since I'd observed like this. No big note taking, locate, look, move on. Kind of a slash and burn style, but it was fun for a change. I did change eyepieces when I felt there was something possibly worth digging the detail out of, but it had been exhilarating. I had stalked the bear, and came away with a great night's experience. I have to do more of this!

Other than one or two other observers puttering around, I was the only other one still awake. The fog had filled the valleys and Coe was dark, and nary a hint of dew. Some light lit the underside of the low clouds blanketing Morgan Hill below us. But Gilroy and San Jose were gone.

One of the observers came by and asked how I was doing. We chatted briefly and I said "look at the clouds in the east"... he looked..... and I said... those over there.... the ones 20,000 light years away.... The summer Milky Way was billowing up.... and the Big Bear was heading down.

It was the perfect finish to the night.

I turned in and slept peacefully. When I woke in the morning the valleys were all under fog.

I drove down the hill and, entering the fog, felt it was somehow taking me from my life as an observer, back to what I do the rest of the time.

I'll be back though. I need to take out the Hunting Dogs, next time.

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