My Observing Log: May/June 2001

1:00 a.m. 6 May 2001 PDT (2001–05–06–0800 UTC)

For the first time this year, I stayed up late enough to observe the red planet. As is usual practice for me, I intentionally did not look up which face the planet would be revealing to me at this hour, but one look at 208x (6 mm Radian), even at the initial 3 arcseconds or so of seeing and thermals, was enough to tell it was Syrtis Major. But aside from that nothing could be seen for the first 10 minutes.

Fortunately, it was cool but not cold out—a typical late spring night for Los Angeles, at perhaps 55 degrees. After 10 minutes, the seeing was still sporadic, but I had enough moments of steady seeing to detect a distinct blueing of the northern extremity of Syrtis Major, a pill shaped area perhaps 20 degrees of latitude in extent. A few minutes more of patient waiting revealed a secondary patch of blueing, much smaller and fainter but still evident, ensconced in Syrtis Minor.

The image was wavering in and out, but I was later surprised at how much real detail I could see. In the north, I could just see the shark's tooth patch of Utopia, beginning to rotate out of view, and seemingly touched with one small cloud. I think, but I am not quite sure, that I saw the northern polar cap, barely visible as a whitish light somewhat clockwise of Utopia. (This is with a star diagonal.) I tried using a Wratten 15 (light yellow) filter, but the view was unimproved. Perhaps bad seeing minimizes the benefit of the filter.

In the south, I made out the split of Mare Tyrrhenum and Mare Hadriaticum, fading into Eridania. This was to the leading southern edge. To the trailing edge of Syrtis Major, I saw twin fingers extending toward Aeria. I did not, however, see Sinus Sabaeus. I wouldn't say it wasn't there, since I am not familiar enough with Martian geography to have remembered to look for it there, but it was not so distinct that I saw it without trying.

Hellas seemed much subdued. I could see some vague whitening toward the Martian south pole, but nothing persistent. Perhaps what I saw really was the south polar cap, but I couldn't be sure. (Contrast this with the north pole, where I am aware of nothing that could be confused with the polar cap.)

All in all, not bad for a half-hour or so of casual viewing!

10:30 p.m. 19 May 2001 PDT (2001–05–20–0530 UTC)

Lockwood is the dark sky observing site for the Los Angeles Astronomical Society, of which I am a member. You are supposed to get there by twilight, so you can set up while it's still somewhat light out, and also so you don't disrupt the observation (and imaging/photography) of others who got there on time. Moreover, even though mid-twilight isn't quite dark enough to do quality deep-sky observing, you can still see more at Lockwood at that time than you can back in town during deepest night, so getting to the site on time also affords you an extra hour or so of observing time.

Well, you know what they say about best-laid plans.

By the time that Opus, my 5-inch SCT, and I were done ganging agley, it was 9:00 and I was just setting out from Los Angeles's west side. Needless to say, it was already dark, at least by city standards. Fortunately, I didn't encounter any traffic along the way and drove the 85 miles to the site—the last 10 or so are kind of slow, too—at a decent clip. (I won't add just how decent the clip was.)

Fortunately, the sky made up for things by being quite clear, although there was evidently a bit of high haze, because the limiting magnitude, I guessed, was no better than about magnitude 5.8. The light dome from Los Angeles was also more prominent than usual.

I said my hellos (there were a lot more people on this mild night—never below 50—than the last few months), and then got straight to work setting Opus up. No time to waste.

My first target of the night was NGC 4565 again, that flat, edge-on galaxy. Here, too, the haze made itself evident, as a lowering in the contrast. In previous months, the dark lane was possible, if not exactly easy, to see. Tonight, however, I just couldn't be certain I was making it out. I certainly could not tell which face was the more exposed. (I think it's the south side.)

Next up was one of my new objects, NGC 6819. This seventh-magnitude open cluster is just about 5 degrees south of delta Cygni, and it's rather a little gem. It's small, perhaps 4 or 5 arcminutes across, but very rich, and it has an interesting checkmark shape to it, with the long arm extending to the east. Wonderful—I recommend it, heartily.

I turned the scope next to NGC 6210, a tiny planetary nebula in Hercules. It is not too difficult to find, being more or less in the chest of the great hero and bright too—about ninth magnitude. However, what it is is difficult to identify. It is only about 10 arcseconds across, and that meant I had to magnify it considerably before I was sure I had located it. At about 160x, the background was made sufficiently dark for me to make out a faint ring of nebulosity. This ring seemed to me to be elongated east-northeast to west-southwest, but the digital sky survey shows it to be more east-southeast to west-northwest.

Much better was another planetary nebula, NGC 4361. It has a magnitude of about 10.3, but it is also about 2 arcminutes across, around 1/15 the width of the Moon. You'd think that that would make it harder to see than NGC 6210, but it doesn't. The problem with NGC 6210, after all, is not that it's hard to see, but that it looks just like a star, except at high power. NGC 4361, on the other hand, looks very nebulous at any power. It is in Corvus, about one-third of the way down the middle of the quadrangle, and another recommended object.

At this point, the head of Scorpius was high enough for me to take a look at M4. In town, this broad globular is washed out, if it is even visible. But under dark skies, even small aperture suffices to show splendid detail. The well-known line running north-to-south down the center was easy to see, and the cluster was resolved well into the central bright spot.

In contrast to M4, M80 is much more compact. Through Ben Kolstad's 7x50 binoculars, M4 could be seen as a hazy spot, but I had to guess at which dot of light was M80—it certainly was not extended at that low power. Fortunately, M80 takes a decent amount of power; I could see slightly increasing resolution up to about 100x or so.

Having observed the winter and early spring sky for a number of months, it was a mild surprise to see some of the objects of summer come rising up. I suppose, with it coming up on late May, that I shouldn't have been so startled, but it was at least a welcome surprise. M27 was only about 15 or 20 degrees up from the horizon, but it's always a magnificent sight, and even with 5 inches, it was possible to see the ends of the dumbbell shape extend toward the fainter ends of the "football." After not seeing it for a number of months, the size of it also startled me. Even at lowest power (39x), it is still very large indeed.

Speaking of size, I remember when I first turned Opus on M57, the Ring Nebula, and thought it tiny at 50x. No more, though. After looking at tiny planetaries (like NGC 6210), the Ring also looks big, though not of course as big as the Dumbbell. The dark sky seemed to make the usually darker center of the Ring less distinct than usual.

My favorite globular of all in the night sky is M22, in Sagittarius, just off the top of the Teapot, lambda Sagittarii. Follow a line northeast from lambda, through a triplet of sixth or seventh-magnitude stars, and there is M22. The beauty of M22 is not so much its size or its brightness, for there are both bigger and brighter globulars. But M22 has a handful of fairly bright stars across its face, and as you draw your eyes around it, averted vision makes them brighten and dim in turn, and the cluster fairly seems to twinkle back at you.

M7 is otherwise known as Ptolemy's Cluster. The stinger stars of Scorpius point straight toward it, and it is one of the best clusters for urban observing. What I noticed under dark skies, however, is that it is similar to M44 in having, really, a first layer of very bright stars, and then almost nothing in the way of second-order stars. It therefore doesn't look as different under dark skies as does, say, M35.

Finally, next to Mars (the seeing was so bad that I didn't spend too much time on the red planet) on this night were two brilliant showpieces of the summer sky, M8 (the Lagoon Nebula) and M20 (the Trifid). M20 was, as always, a delicate flower. Photographs don't adequately convey the fragile nature of this reflection and emission nebula. I tried in vain to find the separate petals that give this nebula its name. No such problem with M8; the dark lane running through this one stands in stark contrast. And it carries with it the brilliant open cluster, NGC 6530, which would be one of the best-known clusters in the sky, if it weren't so tightly associated with the Lagoon.

I wasn't quite ready to quit, but it was already past midnight, and I wouldn't make it home until 2:00 unless I started tearing down that moment. But I'll be back—you can depend on it.

11:30 p.m. 3 June 2001 PDT (2001–06–04–0630 UTC)

The skies above the west side of Los Angeles have been oppressively cloudy night after night lately. To add insult to injury, the days have often been at least partly clear (note wording), but then the marine layer moves onshore and the nights are socked in.

So it was against all odds that the marine layer actually mostly broke up late this evening. It was near full Moon, and there was still a good amount of high-altitude cirrus clouds and haze, so I didn't really consider doing any deep-sky observing. Instead, I decided I would do another Mars session.

I did a similar session in the early morning of 6 May, and the central meridian at the time was about 280 degrees. This evening, the CM was closer to 355 degrees. It took about 10 minutes for the C5+ to cool down; the cooldown period was so short, in part, because it was a very mild evening. Even at this late hour, it was probably about 60 degrees. The seeing was not great—after the cooldown, there was still about 1 to 2 arcseconds of seeing left, in the vicinity of Mars—about 20 degrees altitude. It was probably better higher up in the sky.

At first, it was difficult to make out anything other than a general darkening toward the (celestial) eastern portion of the planet. Then, after a couple of minutes, I could detect a small north polar cap and a much larger and more distinct south polar cap. We are coming up on the end of the Martian southern winter. I also recognized the two main dark patches of Mare Acidalium and Mare Erythraeum. (As is my general mode of operation, I go into each Mars session cold—I don't compute the CM first, so that I can just let what I see guide me.)

After a few more minutes, I was able to see even more. Last time, I mentioned that I did not notice Sinus Sabaeus. This time, I saw it rather distinctly, but it also seemed almost connected with Mare Erythraeum. The same went for Sinus Serpentis to the south. Further north, Mare Acidalium appeared smaller than it did last apparition, while the patch toward the leading (Martian eastern) edge, including Ismenius Lacus, looked darker to me than last apparition. I was also able, just barely, to make out the dark body of Syrtis Major, disappearing along the leading edge. Finally, there was a morning cloud, right at the trailing (Martian western) edge, right at the equator.

As always, Mars rules! :)

9:30 p.m. 13 June 2001 PDT (2001–06–14–0430 UTC)

Ben Kolstad and I took the C5+ out for a turn on Mars last night, and even after cooldown (which didn't take long, as the weather out here is very mild), the seeing was noticeably grotty—I would say about 3 or 4 arcseconds on average, and predominantly in one direction, based on the turbulence seen in the eyepiece: north to south. In Santa Monica, that is roughly blowing off the shore. It hadn't gotten better by 11 p.m., and we gave up at that point.

The best the seeing got, in a very few moments over about an hour of observing in two shifts, was about 1 or 2 arcseconds. Even at that, Mars did divulge some of its details. Syrtis Major, Hellas, and the NPC were the most obvious and immediate features to come out, and at those best moments, one could even see the shape of Syrtis Major. I could also make out the "promontory" of Syrtis Minor. I was surprised somewhat by the subdued appearance of Utopia, whereas the two small dark spots, Stymphalus Lacus and Alcyonius Nodus, could be seen only intermittently but without undue effort. I did not notice any bright area at Elysium, nor between Syrtis Major and Syrtis Minor, but it is probably difficult to do so without filters, and we didn't use any.

Finally, in one good spot, I could see Maria Tyrrhenum and Cimmerium, but only as a pair of vaguely separate dark patches. There was no real contrast between them.

Oh yes, the magnifications we used. Ben and I started on the 6 mm Radian, for about 208x, but then shifted down to the 9 mm ortho, for about 140x. The image through the ortho was very good, considering the seeing, and even the short eye relief wasn't an issue, since Mars is so small that one can back off from the eyepiece and still have a substantial amount of field surrounding the planet.

9:15 p.m. 23 June 2001 PDT (2001–06–24–0415 UTC)

Ben Kolstad and I were rather pleased that the new Moon fell this month on Thursday the 21st, as that meant the dark sky party would not be the 16th, when we would both be at his graduation party, but the following weekend instead.

Plans fell apart when Ben was unable to go on the 23rd because of a rather bad cold. I decided to go for him, since I am a kind and giving soul. I packed my things (there aren't very many with a 5-inch SCT), and set off.

Halfway there, I thought to myself, "Well, you know, I never did check the newsletter. Suppose we have the date wrong." I passed a truck and continued, "Nah."

But you're ahead of me, I'm sure. I arrived at the site and the gate was closed. Not yet despairing, I drove on to the second gate, and that too was closed.

What to do? Fortunately, I stopped the car engine and got out, and immediately I could make out some people talking. I wasn't sure what they were saying, but something about the tone of their voices suggested that they were talking astronomy (what is it about astronomy talk that is so characteristic, I wonder), and that was good news.

"Hello?" I called out.

"Hello," came the answer, after a sudden break in their conversation.

"Is the star party this weekend or not?"

"No, it was last weekend. This weekend is at Griffith." The LAAS holds its monthly public star parties at Griffith Park.

"Well, can I come in and observe anyway?"

"Sure, come back around to the first gate." I was sure that as I got back in my car, I heard someone mutter, "Ah, OK, I'm not the only one confused around here."

The diehards were there, making about 5 telescopes in all, and about 8 or 9 observers, at least while I was there. It turned out that since Mars was in the news, the LAAS decided it would strike while the iron was hot, so to speak, and have the public star party at the height of opposition fever. Technically, opposition was nearly two weeks earlier, but closest approach was just on the 21st, and Mars has been well-placed for viewing for at least a couple of months, and will be for another couple as well. (From the way the news media covers the event, you'd think that Mars was only here for a weekend visit, and then would be gone for another two years.) The only way to do that was to shove the dark sky party back to the 16th—and yes, it was in the newsletter!—so for this one time, Saturday was Mars's—that is, Tiw's—day.

But all's well that ends well, I suppose, and I took advantage of the relatively empty grounds. I set up in a peach of a spot, affording me a good view of most of the southern skies, and I set up Opus in a flash. First object up was another new object for the 5-inch SCT, though not for me. NGC 5139 is better known as omega Centauri, one of the largest (if not the largest) globular belonging to the Milky Way. I found it just as it was heading into a clump of trees. At Lockwood's latitude (about 34.5 degrees north), NGC 5139 is very low indeed along the southern horizon. At its abysmal elevation above the horizon, it was difficult to make much detail out, but I was impressed by its overall size, and I think I made out a broad brightening along an arc bowing outward, from northwest of the cluster, through the southwest, to the southeast.

M4 was next, and I was again awed by how much sky brightness affects the view of this. Some clusters, like M53, are only moderately affected by the sky brightness, but M4 is not one of them. Being so close, it appears larger and sparser than it really is, and is a frequent victim of light pollution. Here under magnitude 6.2 skies, the north-south line (which is a little off from north-south, really) is prominent; it is essentially invisible to small scopes from the city.

Having seen omega Centauri, I moved on to another famous deep sky denizen of that area, NGC 5128, otherwise known as Centaurus A. This is a fabulous photographic target, but it's surprisingly faint for smaller scopes. I think I may have made out the generally southeast to northwest dust lane, but I'm not sure. In any case, if I saw it, it was very tenuous.

I moved on to NGC 6304, which was a new object for both of us. It's a small, condensed, unassuming globular, about 7 arcminutes across, at magnitude 8.4. It was easy to see, though there was precious little detail. It seemed odd, almost like an hourglass, with the ends of the hourglass oriented east-northeast and west-southwest. I followed that up with NGC 6520, which turned out to be a disappointment in small scopes, in my estimation. It is really an unspectacular grouping, having an oval shape that extends roughly northwest to southeast.

Struve 1999 was a nice little pick-me-up after that. It's a easy little binary, magnitudes 7.4 and 8.0, separated by about 12 arcseconds. The brighter star seems a very pale gold to me, and the dimmer star a pale blue, but that might just be a contrast effect.

The good surprise of the evening, as far as I'm concerned, was NGC 6940, an open cluster in Vulpecula. It's a big one, about 30 arcminutes across, and it's nice and rich, with about 50 to 75 stars easily seen in 5 inches. It has a bit of a conic shape to it, and looks as though it were strewn upward from the southeast.

Surprise or not, though, the celebrity was the Veil. I sighted it first without a filter, and although I could see something, it was not an inspiring view.

Then the UltraBlock (a narrowband filter from Orion, who apparently need to call everything Ultra-something-or-other) went in, and wow! What a view! Everything stood out in pretty stark contrast, as deep sky objects go. NGC 6960 had a bright slash from west-northwest to east-southeast, just next to that star, and NGC 6992 was highlighted by an utterly beautiful and huge west to north to east arc that covered the whole field of view at 39x. Simply outstanding! To think that a dying star blew all that out there.

As a nice little chaser, I spotted NGC 6819, another open, this time in neighboring Cygnus. It's relatively small and delicate, about 5 arcminutes across, and shaped like two horns, or maybe a thin butterfly.

The seeing was decent, very good actually for Lockwood, so we all spent some time looking at Mars. (A lot of time, some of us.) It wasn't as nice as it has been in town, but we were able to make out Mare Sirenum and Mare Cimmerium, and possibly Stymphalius Lacus in all of the scopes.

All in all, a beautiful night, and one I spent largely chasing down new objects, which isn't that typical for me—I usually enjoy going back over some old objects, too. Just the same, I thought I'd give Ben a little ribbing, and the next time I saw him, I told him that without him beside me pestering me for directions and information about this and that in the sky, I was able to get through twice as many new objects as I usually do. Fortunately, Ben and I are good friends and I'm quite certain he won't post a follow up to this informing everyone how insufferable I am.

Incidentally, I should mention that while we were observing, we heard every now and then a loud growling nearby. Someone mentioned that there lives a lion tamer in the neighborhood, and that was the lion we heard. I'm glad it was a tamed lion, who was likely to be inside a pen, fed, and cared for, as opposed to a mountain lion, who was likely to be wandering around and hungry!

Copyright (c) 2001 Brian Tung