Rehoboth Skies Part III

[Rotorhead]

Like Paul D, I did not have an observing plan, since I anticipated long lines of folks wanting to see the Veil nebula all night. However, I took along a finder chart for Uranus and Neptune, just in case, as well as a quickly torn-out page from the latest Astronomy mag with a new (for me) planetary nebula, and a finder chart for comet 4P Faye (sorry, Mark, it wasn't comet Swan). After a cloudy and disappointing summer unsuccesfully chasing comet 177P Barnard, I really wanted to nail Faye.

Arriving just before 5pm, the field was already beginning to fill with scopes, so I set up next to my car and was surprised to have one visitor already on the field who came over to talk about my telescope. I thought that would augur for a good evening of guests, if they were already showing up before dark. Jim and James, and Bill L showed up shortly afterwards, followed by Paul D, and we all prepared for an evening of public viewing. Except the public hardly showed up at all. There was a trickle of 'public' most of the evening, but no lines despite steadily improving skies. The few people who showed up began to ask for certain targets, so most of us began swinging our scopes left, right and straight up from one target to the next, rather than stay on our intended targets.

A nasty cloud deck rolled in rapidly at around 8 pm, but the west edge of it was visible before the front edge reached the eastern horizon, and it seemed to usher out the last of the moisture, because the sky just kept getting clearer and clearer after that. During the rest of the evening, neither my telescope nor my Telrad got the least bit damp despite steadily falling temperatures that bottomed out at 38 degrees just after midnight.

As the requests rolled in, I variously viewed M31, with M32 and NGC 205 visible in the same FOV, M13, the Double Cluster, M45, M57, M33, M27, M11, M39, and my original target, the Veil nebula. I was really surprised that both the Witch's Broom and Waterfall segments of the Veil were very visible to all who observed them, including fairly young children and many adults. I feel that it helps in these situations to have a 'visual aid' in the form of a large-size schematic of the intended target, so that the uninitiated observer knows what the target looks like before they step to the eyepiece. In this way, I have had good luck showing targets as faint as M81/M82 to quite young children. For most of the nebular targets, I used an O-III filter, with a UHC filter for M27 (I feel that the O-III filter makes the Dumbbell so bright that it looks fake). I also used the O-III filter to good effect on the Merope Nebula in M45.

During a lull in the already slow action, I decided to find NGC 6781 in Aquila, the feature nebula of the Deep Sky segment of the latest Astronomy Magazine. Heeding the advice to search for this planetary with an O-III filter, I managed to find it within a few minutes of searching. Paul D also looked for it, but did not manage to find it without a filter. As soon as he put on an O-III filter, he found it immediately. We both agreed that this was an interesting planetary, with potential for dark sky observing.

By this time (perhaps 10pm) the Double Cluster and the Andromeda galaxy were both naked-eye visible, which is remarkable for the club site, and a faint but noticeable Milky Way was running from 45 degrees above the west horizon right through Cygnus to near Casseopeia. That is a remarkable event for this close to Providence. At this time, I had a few more requests, for M1 (inexplicably very dim even with filters - too low, I think on the bright eastern horizon), M33 (nearly invisible) and M74, similarly poor. My feeling is that there was a lot of upper-level turbulence that was giving poor seeing on dim objects. However, NGC 205, near M31, was easily visible to trained eyes in the same FOV as M31/32, and even to untrained eyes when centered in the FOV. Illogical, to quote my favorite Starfleet science officer.

Since the only remaining folks on the field were a few true astronomers and some diehard guests and members of ASSNE who had been cooped up in the clubhouse until just now, Paul D and I decided to commence the search for comet 4P Faye. My finder chart seemed clear enough, with several distinct asterisms to guide us, but the comet remained elusive. I had forgotten over the winter just how dim Pisces can be, so I found that I had chosen two guide stars incorrectly, and at Paul's suggestion moved to the two real Pisces stars that should have placed me within one Telrad field of the comet. Using nearby M74 as a measure of the seeing, I was ready to throw in the towel, blaming upper-level disturbances for my failure. Then Brian came over and said that he had seen the comet at his telescope, so that caused me to reconsider and seek out a new strategy. I had just started an 'expanding square' search when Paul called out that he had the comet in his eyepiece. Sure enough, when I glanced in the eyepiece the comet was very obvious even before I made my usual large focus correction. A comet just looks like a comet, and there is hardly any doubt when it actually has a tail and a halo around the coma, as this one does. Still having trouble with the dim Pisces stars, I finally located the comet about 15 minutes later. I was a bit shocked when I realized we had been searching for something like 90 minutes for this beast. But considering that it was about 4.5 to 5 degrees off of the predicted location, and mag 10.4, I'm surprised we found it at all. It is a tiny comet with a very ephemeral single tail, but it is bright and obvious once it is found. We both studied it for a while with no visible movement (it was centered between two stars which would have made movement quite visible).

Flush with victory, we decided we had had enough excitement for the night, and we retired to Dunkin Donuts to tank up and unwind.

I have some thoughts for future Rehoboth Skies, but that will be for another night.

[Dan Chieppa]

Bob,
Very nice report. Sorry I missed the event but the Maine trip was planned several months earlier. Glad you found Comet Faye. It's beyond the range of my 80mm and would be a test for my 5-inch.
Clear skies,
Dan

[Pete]

But considering that it was about 4.5 to 5 degrees off of the predicted location, and mag 10.4, I'm surprised we found it at all. It is a tiny comet with a very ephemeral single tail, but it is bright and obvious once it is found.

This is strange. When Brian and I observed Faye thru Brian's 12" it was where Guide 8 placed it, but all we could see was a very faint nucleus about 2 or 3 arc-seconds in size. Guide 8 data had been recently downloaded from Harvard's database.

Wonder what's going on? Did you have a chance to view thru Brian's scope Bob?

Pete

[Rotorhead]

Well, Pete, I have spent about as much time trying to reconcile my various programs as I did looking for the comet last Saturday.
I'm sure that part of the problem is the dim stars in the vicinity of Faye at Rehoboth Skies, and a difference of opinion among The Sky, CNebulaX, and Deep Sky as to what the star fields looked like around Faye at any given time. Paul and I both think that Deep Sky gives us the most likely candidate for the 'hourglass' shape of the stars around Faye when we saw it, and if so, then the comet was probably where it should have been. In The Sky the 'hourglass' asterism was at approximately 2h 09' 10" and 10* 08' 50". If you could, Pete, run your Sky program back to the date of Rehoboth Skies at 10:30 to 11 pm and see if it shows Faye anywhere near there. The Sky version that I have was plotting about 1 degree from there, and showed no hourglass asterism, so therein may lay the problem. I was probably exaggerating when I said 4-5 degrees, but it sure seemed that bad after such a long, frustrating search. I probably would have quit if I hadn't known that you and Brian had seen it.
Of course, Faye must have been very near to where you and Brian had it plotted, because you both saw it independently, and after I had it in my scope, either Brian or someone who had looked in his scope (I really think it was Brian) said, 'Yes, that background asterism is the same as we saw'. We couldn't have all seen the same asterism unless we were looking at the same part of the sky. The problem is my Sky program, most likely, and I think Paul was looking at my finder chart. I had updated it with Harvard, but I don't think The Sky is that good a program, especially in the sense that it does not generate recognizable star fields at higher powers.
As to the shape and clarity of the comet, it was a stretch to see the tail in Paul's scope, and it required averted vision (for me, anyways) and even then the tail was very ephemeral. With the 15" the tail was obvious, even with my 30mm ep, which I never changed out from my area search. Remember, we were looking at it about an hour or so after you did, so it was just that much higher from the thicker air at the horizon, so that may have made a difference. And I do believe the simpler optics of the dob will preserve a really faint, nebulous object better than the SCT. Just my opinion, of course .

[Pete]

Hi Bob,

Your coordinates are within 7' of the position where we observed Faye, so you did have it. Faye was low when we observed it - in fact we'd tried even earlier and couldn't see it. So it makes sense that the brightness is associated with its rising higher later in the evening.

Pete

[NGC891]

Bob, you're correct. I saw the same "background asterism" in both scopes. Of course I felt mine to be superior, mainly due to the much lower frustration levels associated with the SCT. Pete and I plotted the comet in the handbox, but did have to search a little for it...as the scope was slowly slewing to the coordinates I spotted the background asterism that was on Pete's printout and went back to it after the scope stopped. It did take almost a minute to get it centered in the eyepiece.

[Rotorhead]

Thanks for the comments from both of you. It is strange how supposedly computer-generated star charts can look so different. I have The Sky loaded to show down to Mag 30.0, which I usually filter to show only to Mag 16.0 when plotting deep sky or faint objects. Since I got Deep Sky, I have found it to be a much superior plotting program, but I have not spent the time to learn it as well as Paul has. My bad.

As to go-to vs. push-to, I still enjoy the hunt. Even my frustrations are instructive, and have helped me learn the sky a lot better. I have an easier time finding things when I have some peace and quiet and can think the problem through, and Rehoboth Skies did not afford that opportunity. Don't get me wrong, I love demonstrating telescopes for the public almost as much as observing on my own plan in a dark site. However, after an evening answering so many questions and having to think of the polite way to answer them, my brain was already a bit dimmer than the comet, so that made the search a little more of a challenge. But when I hear some guys terminating their night because of battery death, I am happy that my scope will run as long as I can push it. When I am seriously brain dead late in the evening, I can always push the scope to one of my old favorites and just sit there enjoying it.

But 4P Faye was a challenging hunt, and one I will long remember. It is just so satisfying to know you found it by puzzling over the charts and trying, trying, and trying again. My simple Marine Corps brain prefers both the simplicity and the hard work, and the idea that, after a long hunt, your quarry is finally in your sights.

[Paul D]

Bob,

I couldnt have said it better myself. There is a true sense of accomplishment when hunting for these objects. I totally understand why people use goto because most dont want to take 90 minutes hunting one object. I am also convinced that we would have found it sooner if we hadnt had to answer questions so often. For us a few minutes answering a question means that our fields drift and we start all over again.

Well since I was never a Marine I guess I am just plain simple minded.. LOL... Seriously you are the master of the telrad. You can nail a target within a few degrees of where it is. I was impressed that in such a blank part of the sky you managed to get your telrad in the same field mine was in after I had spotted Comet Faye. I on the other hand like the finder scope and star charts to hop my way there.

The star chart you had was great for the guide stars but it failed to put Faye where it actually was in the sky. I knew for a fact I was in the right part of the sky by using your chart. I didnt have the DAS chart of Faye that night because I didnt think there would be time to find it.

In the end the night was very rewarding and the hunt was worth every minute I spent looking for it. I wouldnt trade it for the world.

Paul D...