Sunday, August 30, 1998

Thank heavens for the magic carpet!

It was a hot day in Los Gatos, and I was sweating repairing part of the new deck in our backyard, where the contractor did what turned out to be not so wonderful work. In the afternoon heat, I noted our grapevines now beginning to turn brown and the leaves in the neighborhood trees showing the first yellowing, a clear sign that fall is on the way. This is probably my favorite time of year at Fremont Peak, with the summer Milky Way high overhead at dark, and the first of the winter constellations visiting as dawn breaks after a night of observing. I had been at Sierra Buttes the week before, and was fully satisfied with the photon cache until next third quarter, but, something nagged at me. The weather was so nice, the sky so clear, and the moon would be down just after midnight. I had thought about going to a club meeting in San Jose, but hours of milling around in a small hot room with a crowd helped me to a quick decision. I could finish my work, do the BBQ, clean up and be at the Peak no later then half past ten.

So, I asked my wife, Pat, if she'd like to leave the kids with her sister and come out to the Peak with me, just adults this time. She was enthusiastic, and by 9:15 p.m. we were packed and on the highway, Jupiter up and seemingly beckoning us to come observing all the way down highway 101 to San Juan Bautista. What a great trip, having virtually no heavy traffic! Up San Juan Canyon Road, the drive was completely different at night. Off to our left sat the city of Hollister, lights glowing over a wide and growing portion of the valley floor. Fremont Peak will continue to have to fight for its skies, unless mother nature would intervene as was common many years ago. We needed the fog to come in and blot out civilization.

Pulling into the southwest parking lot, overlooking Moss Landing and the Pacific Ocean, I could tell there was some fog. Rashad and Rich were there, along with perhaps half a dozen other observers. Rich came over and said the fog was moving out, off the coast, and we'd probably have a bright sky. For me, the sky was already bright, as the moon was still somewhat high. I would set up, and relax until it set. Pat and I took a walk across the park to the Fremont Peak Observatory. The park seemed mostly devoid of astronomers, other than where we set up. But, we did find the observatory open, manned by Mojo, Peter and Ed (?). They were testing out use of The Sky software to use with the 30" Challenger reflector. We stayed for a bit, then walked back to our side of the park.

Now, the fog looked as if it were moving in. I took my scope, the 14.5" f/5.6 dob, and pointed it toward Gamma Andromeda, dropped down a bit, and with a quick sweep had the nice dim edge on galaxy NGC891 in view. Fun! Even with the moon up and some city lights showing, I could see the length of the object and its dust lane. Rashad and Rich came over, marveling at its dimness, yet the ability to detect detail. I even amazed myself that I stopped right on it.

After the moon set, I began what was to be a relaxed session, with much sharing of views, going to other telescopes, and talking with newcomers to the site.

I decided to begin with the objects I had remaining in Pisces. They are all listed in the NGP freeware database program I used to make my Herschel list, as magnitude 15 or dimmer. They were sorted brightest to dimmest magnitude, then by R.A. I do not much like using magnitude as the determinant in what I can or cannot see, so I will refer in this report to surface brightness (i.e. sb=13.2).

The first object for the night, aside from a few showpieces for warm up, was NGC213 (U00436 = M+03-02-023 = Z457-026), a class SBa galaxy at RA 00 41 10.0 Dec +16 28 09. It measures 1.7x1.4 with sb=14.1. The object appeared elongated to me, with a bright core. I also felt I saw IC1572 in the same field. I found this galaxy by finding Algenib in the Great Square of Pegasus, then locating SAO 92099 (64 Psc) at mag 5.2 just off the corner of the square. The galaxy is just under one forth the distance back to Algenib from 64 Psc. Easy location, dim object.

Next I move to NGC742. This one is too easy to locate. Anyone who has found M74 in Pisces knows it is right off the mag 3.7 star 99-Eta Psc. Remembering that star, all one needs to do is go to the sharp bend in the constellation lines for Pisces, which is located at mag 4.3 Alrescha (SAO 110291), or 113-ALPHA PSC. NGC742 is just about on a line from Alrescha, one forth the way up to 99-Eta Psc. In the field with NGC742 is NGC741, which appears to be merged with IC1751, and UGC1427, away from the other three. I could not tell a definitive shape for NGC742, although it is listed as elliptical and very small at 0.2x0.2, which explains the surface brightness of 10.8.

NGC7562 is located by finding mag 5.2 star 7-Psc in the Circlet of Pisces, and looking toward four stars in a tight grouping ranging in mag from 4.7 to 5.4, toward Markab, the corner star in the Great Square of Pegasus where the horse's neck begins. From 7-Psc, go just over 1.5 degrees (just under half way) to the grouping of four stars I've mentioned. You need to take care in this area, as there is a dense galaxy cluster nearby. When I found this object, I saw perhaps four galaxies in the field. NGC7562 was bright at sb=12.8, and good size at 2.2x1.5. The other galaxies were too fleeting to tell much about them. I felt I was seeing NGC7557 and NGC7591.

Located mid-point between mag 4.6 Circlet star 18-Lambda Psc and mag 5.2 Circlet star 7-Psc is NGC7685 (U12638 = M+01-59-087), at sb=14.1 (dimmest in group) and 1.9x1.4 in size. NGC7687, in the field, is a small galaxy with a bright core, sb=13.6. Also, close together are NGC7682 and NGC7679, at sb=13.3 and sb=13 respectively, and both about the same size, roughly 1.0x1.3.

NGC7797 (U12877 = M+00-01-011) was the last object I would attempt in Pisces for the night. It was way up in Dobson's hole now, and I needed a break.

This observing session was different from most for me, as Alan was not along and I was working from Tirion Sky Atlas 2000 with the grid overlay to determine where uncharted objects were, and I had two large volumes of Uranometria-like charts that I had printed from The Sky. Still, these were no substitute for a laptop in the field. I did enjoy myself though, as it was a different type of challenge with different tools!

So, the last object in Pisces. I thought this was kind of humorous. I often joke about how bright the moon is, and in fact, how bright Jupiter is. A thread on sci.astro.amateur was titled something like "you know your a deep sky observer when..." and I posted "Jupiter ruins your night vision". Well, to find NGC7797, I had to hold up my hand to block Jupiter from view so I could see the mag 5.9 star 22-Psc. I needed that star in order to use it to draw a line toward the NGC object from the mag 4.6 Circlet star 18-Lambda Psc. The NGC was just about half again beyond the distance from 18-Lambda to 22-Psc. The object was very dim, mostly an averted vision view. It is alone in the star field, sized at 0.9x1.0, a category Sbc and unbelievably sb=13.4 (it looked much dimmer to me, maybe my eyes were getting tired, or I was).

I will finish up a few of these constellations when I go next to the Sierra foothills, which I hope to do next new moon.

I took a break. I walked around, had something good to drink, joked around with the remaining observers (Rich and Rashad), looked through their telescopes, and generally stretched my legs and enjoyed the big view of the heavens.

The fog had come in very nicely while I was observing, and the night had become reasonably dark. That fog is the key to a good night at Fremont Peak. It is the magic carpet that lays to waste the light pollution that can turn a good night observing into a frustrating one, blanketing and burying it like a thick carpet. Thank heavens for the magic carpet! I was enjoying the ride tonight! This was more like the Peak of old.

I would finish three more objects during this "short night" of observing. Off into Perseus, I first looked at NGC1138, and found it sitting by itself, very, very dim, almost stellar. It is not difficult to star hop to, since you use mag 2.9 Algol and mag 4.0 27-Kappa Per to form the base of an almost equilateral triangle, with NGC1138 being the apex of the missing angle on the M34 side of Perseus. This galaxy is classified as SB0, but its size is larger than I think listed at 1.1x0.9. It surface brightness is also somewhat misleading, as it sure appears dimmer than 12.6.

NGC1167 was next, and I was getting very tired now. All the deck work in the hot sun in my backyard during the day was now beginning to catch up to me. But, my eyes were still open so...

This one is what I call "too easy" to find. It is fun to get a "gimmie" and here was a good one. Following the line in Perseus that contains Algol, there are two stars at the end of the open side of that line, mag 4.7 17-Per and mag 5.0 25-Per. 17 point to 25 and just a tick off 25 is NGC1167. There is a bright star on one side of the field of view, and a nice chain of three dim stars opposite it in view. With averted vision the galaxy appears elliptical with a bright core, fairly small in size, but bright compared to many of the others I've looked at. It is type S0, 2.8x2.3, and amazingly, the surface brightness is listed at 14.3 (it does not look that dim to me!).

Now I was on to the last stop before putting away the eyepieces and Telrad. NGC1129. But this would be an interesting hunt, as I would select the wrong side of Algol to look at, and find myself instead counting galaxies int the Perseus Supercluster. One night several years ago, Ed Erbeck and I had the 30" one mid-week night, and counted 17 galaxies in this cluster. Well, here it was again, by mistake, and in my 14.5"scope I counted 7 galaxies in the 2/3 degree field, without really working at it! But, I had to get back to NGC1129 and friends. So, if you used Algol and M34 as landmarks, NGC1129 was about halfway between them. That is really close enough, as you can match up fields of galaxies in this part of the sky, to make certain you are looking at the correct object. Well, I was. In the field as 1129 (U02373 = M+07-07-004 = Z540-006 = Z539-124), a good sized elliptical galaxy glowing ever so dim at sb=15.2. What made it possible to see this galaxy was, it was located between two brighter ones, NGC1130, nearly stellar at 0.5x0.3 and sb=11.9, and NGC1131, also tiny at 0.5x0.5 and sb=12.5. These two bracketed the really dim one. I was also able to, for my last object associated with the Herschel hunt for the evening, see UGC2361, near the edge of the FOV, UGC2361 also is cataloged as MCG7-6-84, CGCG539-119, CGCG540-1 and PGC 10923. I do not have a surface brightness for it, but it is listed at mag 14.06 in The Sky.

That was it for my observing. I prepared my bed. Pat was sleeping soundly. Rich and Rashad pretty much quit too. We pulled out chairs together, sat and talked, joked, looked at the sky naked eye, and had a great time, watching the east growing lighter.

Soon I could not keep my eyes open. I said goodnight, climbed in my truck, lay down on top of my sleeping bag and shut my eyes. There are few indoor meetings that could better this night out, so I felt I had certainly made the right choice. Not a bad 1st quarter moon Saturday! I was soon asleep.

No comments: