| Reports | TAC | Join mailing list |
by Mark Wagner
Last Saturday I piled my 18" OBSESSION into the back of the truck and, with my young protege in tow, headed out toward Fremont Peak around 2:15 p.m. I had expected bad traffic given usual patterns and the fact that this was a major holiday weekend. Yet, as I passed the usual slowdown where San Jose spills out of old El Camino Real toward the south, things could not have been better. In fact, I was not the fastest driver on the road by a long shot, so I was guaranteed a quick trip and reduced odds of a speeding ticket. After a few grub stops, Mimi and I turned up G1 to follow the creek up San Juan Canyon Road to the end, its termination, at the base of what had once been known as Gavilan Peak, but later renamed after Colonel John C. Fremont. The drive up the canyon brings home that we are leaving summer and facing a change of season. The bovine population was busy eating the few shreds of green grasses left, and many were picking green leaves off the trees. The bounty was gone, dormancy and the chill of winter were on approach. All around were the tan and golden hues of California's foothills at the end of summer. Trickles in a stream that just yesterday, or so it seems, overflowed its banks and caused one to slow down in passing.
Spanish Moss still overhung the road from the oak trees spanning above. Looking out from the open ridges halfway up the road, we could see a good fog bank laying low over the coastal cities, and the possibility of a dark night on Fremont Peak. Yet, there was a lot of haze in the air, perhaps from the state's multiple forest fires. So, perhaps dark with reduced transparency. Whatever, we were pulling into the parking lot and found several of our friends already there.
It was hot out. Whereas at my home in Los Gatos one could stand outside in an 80 degree sun, now it felt like the mid-nineties, and of course the paved parking lot was hot, making me think of my toes as small sizzling sausages. But the option of barefoot on the frying pan was even less appealing.
The parking lot was a construction zone. We had less room than usual, but still packed in a good number of scopes. I set up the 18 and shared a cold beer with friends. The sun was dropping and things felt like the old Fremont Peak. But this is a park in transition, which is a topic for another posting. The fog stayed down, the stars came out, and the fun began on a little island of observers at the southern tip of 6 million other people occupied with TV, traffic, and other plagues of modern "civilized" life. We were free, with nothing but the diamond sky to reign us in.
Mimi had come up with me, not as the Messier Monster, but this time, without telescope, just to "be" there. She enjoyed the company of Ray Gralak's son Brandon, while I planned to split time on my scope with my observing friend Ken Head. Ken is seriously looking at increasing his aperture. He currently owns a Celestron Ultima 8", but wants to add 10 more inches. He had asked about working on my 18 together, and I thought could be fun.
At true dark, the fog killed most of the city light to the west. Salinas still made the south bright over the right shoulder of Fremont Peak. But overhead, the sky was good, and the Milky Way was putting on a spectacular show. Not a "Lassen" type show, mind you, but there is still a thrill to look 20,000 light years away at that great galactic arm. We began our observing session, using The Night Sky Observer's Guide, in Aquila. Jack Zeiders was set up next to me, and heard me pronounce Aquila "uh-KEE-luh", and said it is "A-kwill-uh".... is that right?
The first object I found was NGC 6709, a nice mag 6.7 open cluster about 5 degrees SW of Zeta-Aquilae. This is really a fine open, about 13' in size and previously unknown to me. I suspect it is not all that well known, since it is not part of the Herschel list. The cluster is bright and rich, easily standing out from the surrounding field. It has many bright components, some showing fine color (blue and yellow). I felt as if there were dark lanes in the cluster.
I turned the scope over to Ken for the next object, LDN 582. Lucky him, a dark nebula in a bright part of the sky! This would be a challenge. How do you know when you're there? Well, since the object is in a bright part of the Milky Way, you could reasonably expect the star density to dramatically change once you found the intervening construction debris. The cloud was in an easy location, found by following a naked-eye chain of pointer stars trailing off 16-Lambda-Aquilae (the top of the two tail stars). There was a 6th magnitude star described in the book, which also stated the nebula was 45' due west from there. Since my apparent field was 39' with the 20 Nagler, it was easy to move one field west and see that yes, the population of stars in the eyepiece diminished dramatically in that spot. This would be a fun object to hunt in a dark sky, where you could more distinctly see the boundaries. Ken was not successful in "newbie mode" finding on this one. I got it.
On next to NGC 6738. This cluster was poor in comparison to NGC 6709, yet it had its own character. The stars are much more sparse, but it is easy to tell when you are on the object as it has a very distinctive north-south line of bright stars cutting right through its center. Now, I never knew how to determine direction in the eyepiece, I'd always heard some whispered methods, but never really paid much attention. One day at Sierra Buttes, Steve Gottlieb sat down with me and, since he is a teacher by profession, spent adequate time to make sure I understood the method, including estimating distances in arc-minutes. I now get a locator star in the eyepiece, put it dead center, walk away for a minute and read a bit about the object I'm looking for. Then I go back to the eyepiece and see which direction the star has moved toward. That's west. Counterclockwise is north, and so on. It is really pretty easy. And so, it was easy to identify north-south and the chain of stars that marked NGC 6738.
Did I mention how hot is was during the day at the Peak? Well, I was slugging down Coronas (the beer). I guess I had quite a few in a valiant attempt to not dehydrate. But I was a bit loopy. I was having fun, but yes, I was well, having fun. I lit up a smoke. Jack Zeiders, who has forgotten more about observing than I've ever known, started in on me by telling Jamie Dillon, sitting right behind me, that you lose about 1 mag by having alcohol, and another mag by smoking. I figured I was down to about mag 9 for the night, but later, I would prove that my vision suffered little if at all. So, did I mention how hot it was? Even late in the night, in the early morning hours before twilight, it was pretty much shirtsleeve weather. What a wonderful night.
Our next objects were three Barnard Dark Nebulae situated between the two end stars in the tail, 16 Lambda-Aquilae and 12 Aquilae. All three were difficult in the bright sky, and we can only assume we saw them where stars were obviously missing in the otherwise busy field. The description in TNSOG is very good, and in a darker sky there ink-spots would be more fun to track down.
We moved on to another object in Aquila, Planetary Nebula PK36-1.1, or Sh2-71. This object required an OIII filter to confirm, although the star field was not difficult to identify. The location is not difficult, since the outer Telrad circle almost touches mag 4.62 star Alya in Serpens Cauda (63-Theta 1 Serpentis). By boosting the power from about 100x to 170x, we could pick out the mag 13.8 central star easily. The disk is fairly even in brightness and distribution around the central star. This is also an interesting area as the density of field stars changes dramatically just at the location of the planetary nebula, as if we were at a transition point between a moderate Milky Way and a dense area. The change in density helped confirm we were in the correct field while hunting. I found this and the prior object. Ken was still getting his feet wet with the Telrad and big scope.
On to another planetary nebula, NGC 6741. Go ahead an look for this one. It'll prove your star hopping skills if you can pick it out. It is nearly stellar, and is betrayed by blinking it with an OIII filter. It is a nice green/blue bubble, but tiny. What helped here was knowing (from using a computer planetarium program in the field) that there is a slightly concave line of four nearly equal brightness stars, all about mag 8, just outside the field of view with the planetary centered, and a tight double at about mag 8 about 11 minutes to the south, and another roughly mag 8 wide pair of stars just outside the field opposite the line of four. These types of details allow one to pinpoint even the most difficult object at reasonable power, then blow the thing up to try seeing it. It worked. The 12 Nagler showed a small disc. I found this one too, but Ken was getting noticeably better at star hopping, getting within about a degree of the correct location!
After looking for another Barnard object as Aquila (a-kweel-a) dropped more into the light dome of Salinas to the west, we headed over to galaxyland, in the string of fish called Pisces.
We began with NGC 7428, a mag 14 (TNGOG says 12.5), this galaxy is round with a bright core. It is not very large, nor is it very distinctive. It was difficult to see initially, until we found a pattern of stars, two equally bright one with three on a line in between them, then a string of stars coming off one of the bright stars, leading right to the galaxy. Many times, identifying star patterns is the only way to locate a difficult object. In this case, the finding was the fun, whereas observing the object was just a result. If you want to find this object, find the Y in Aquarius and use the brightest member, 62-Eta Aquarii, and the next star down the eastern side of the constellation figure, mag 4.2 90-Phi Aquarii. Place the western edge of your Telrad circle just north of the halfway point between the two stars.
Two galaxies in the same field, in fact, nearly touching each other, were our next target. NGCs 7537 and 7541. Ken found these. They are just off the western-most bright star in Pisces "Circlet." These are fairly bright and easy to identify at mag 13.6 and 12.5 respectively. What was real fun was hunting galaxies in the nearby fields. We found CGCG406-27 and CGCG406-34 both about mag 14.9.
Another pair of galaxies were next, NGC 7541 and NGC 7562. Our target was 7562, and it was easy to find and identify. More difficult was 7541, at almost mag 15. These galaxies are in an easy to id star field, with NGC 7562 being in-line with three mag 9.2-9.4 stars.
NGC 7611 was a blast. Not because of that particular galaxy, but look at the surrounding galaxy field using a planetarium program and you'll see that it is dense. 7611 was easy to find, but initially two other galaxies in the field grabbed my eye. NGC 7619 and NGC 7626 are both about mag 12.3, and easy moderately large round galaxies. NGC 7611 is about 11 minutes SE of 7619, with a mag 7 star about three minutes to the south. Seven minutes WNW of 7611 we found IC 5309 at mag 14.6, and about 10 minutes NNE of there UGC 2510 showed. Roughly 7 minutes NW from there, forming a right angle with two pair of bright stars (three of the four are mag 9) is NGC 7608 at mag 14.9, and by continuing N about 15 minutes you'll find mag 14 NGC 7612. While in the area we also snarfed up NGCs7623, 7631 and 7617. Only tonight did I learn that this rich area is known as the Pegasus I galaxy cluster.
By now I was certain that my other vices were not materially harming my observing. We were having a blast.
Right in the center of Pisces' Circlet sit a pair of galaxies, NGC 7679 at mag 13.3, and about 4 arc minutes away to the east, NGC 7682 at mag 14. My notes do not say much about this pair.
Again in the Circlet, and easy to locate on a line between two brighter stars, sits NGC 7714. 7715 (mag 14.5) and NGC 7714 (mag 12.9) are two galaxies between mag 5.6 and mag 7.1 stars. There is no mistake when you find them. 7715 is elongated, and 7714 is involved (line of sight of course) with the mag 7 star. 7715 is in the Arp catalogue of peculiar galaxies, showing a galaxy over a galaxy. This might be worth looking into more deeply.
NGC 7716 is a mag 12.7 gorgeous spiral galaxy, at least in photos (see the DSS shot). It sits very close to a mag 12 star and has, if I had known to look (right.... good luck here) an Abell Galaxy Cluster (#2631) and Zwicki Cluster (#8895) in the same field. This must be one dim cluster, as I did not have a hint of it.
The last galaxy and entry from TSNOG we looked at was NGC7731, again located on an easy line between two of the Circlet's stars. 7731 is a faint, small, mag 14 galaxy with another mag 14 galaxy, NGC 7732, just perhaps an arc-minute SE.
I don't know much about galaxy clusters, such as Abell or Zwicki, but I can say that my planetarium program shows a lot of the, especially in the area around Pisces' Circlet. I would like to explore the possibility of observing some of them.
We finished the night looking at Jupiter and Saturn through some friends 6" Takahashi and 7" Astrophysics refractors. The views were outstanding, even though the seeing could have been just a bit steadier. Bob Czerwinski asked about using his high power Pentax eyepieces on my 18" and we tried, but they would not come to focus, requiring just a bit more in travel than my focuser would allow. Then he brought out a Tele Vue Big Barlow, and all the eyepieces worked. We were looking at the planets at up to 812x and getting very pleasing results. I have been trying to decide whether to get a 9mm or 7mm for my high power eyepiece, but now, I think I may solve my problem inexpensively with that Barlow.
Feeling the effects of a long hot day and full night of star and party, I was well cooked by 4:30 a.m. I crawled into the truck with my daughter, placed my head on a pillow, and was out.
The next morning just a few of us remained. One went home, two others joined Mimi and I in San Juan Bautista at Dona Esthers for a breakfast of chorizo, rice, beans and black coffee. Rejuvenated, I made it home, sat down in a soft chair and was again sleeping.