I ran across this fantastic article by Shigeki Murakami today, discussing the present and future of comet hunting in the age of the surveys. It is both hopeful and wary, as it describes ways that LINEAR and other surveys have made it a greater challenge, though not impossible, to visually discover comets. Yet it is mindful of the new surveys coming on line, and what those might mean to the visual hunter.
Mr. Murakami and I share many of the same feelings about comet hunting, and both of us went through a period of despair with regard to visual hunting and the surveys. However, like him, I have come back to it through a combination of access to darker skies, new tools, and simply a desire to observe in the style of comet hunting.
So visual comet hunting these days is really more of a way of touring the sky, and if you have that attitude it can be enjoyable. See I guess I don't worry too much about what the surveys are doing. As a comet hunter, you can't. If you do you get depressed and going outside feels futile. But on the other hand, I enjoy sweeping more than targeting a list of objects. However, I think I am finding a balance in those two camps. Sometimes, certain things strike my fancy and make interesting targets. So I think that a combination of sweeping and some other activity will become the norm in my observing habits from now on.
For example, there has been a lot of talk about double stars lately, and I'm somewhat intrigued by trying to see Sirius B. The challenge with this is what tactic to employ that reduces the glare of Sirius Prime in order to pull B out of the halo. My idea is to crank up the power as high as possible and use a moon filter and see how well that tactic works on this. I'll probably start with the 20mm combined with the 2x Barlow and the moon filter. If that doesn't work, I'll try the 10mm and the filter/Barlow combination.
But the point is I think that for me comet hunting is still going to be my preferred method of observing, but it can't be without some sense of success or challenge. Looking for comets is a challenge, but the opportunities of success are quite limited in the atmosphere of all these surveys. So in order to keep things interesting, I need to find additional challenges that do provide for some chance of success.
But at the same time, like adding the computer to the mix, it is wise to be mindful of doing what you can to improve the odds of comet discovery. Get out to dark skies, get as much aperture as you can afford, use computers, know where they are looking and look where they are not. Be a human survey. And most of all, enjoy the hunt for the sake of the hunt. It has got me thinking, however, about a bigger scope. Maybe I should build that 12"...
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Another nice night. This one about 15 degrees warmer than the last, too, which is a nice bonus. I probably would not have gone down to cherry grove in that I'm going to be at the Farm this weekend, but I'm not sure if I'll be able to bring the scope due to space issues and the weather is looking a little marginal (I should set up a clear sky clock for the Farm at some point).
In any case, because of the uncertainty of the weekend I decided to go south and comet hunt while the weather was nice.
Congratulations to William Bradfield who scored a visual discovery in Australia! And a very tough spot, too, very low on the horizon, but bright, at 14 degrees(!) elongation. This is going to be a tough one to observe, but it might be possible along with LINEAR 02T7 in the morning skies in late April. It will also appear in SOHO images over the next few days.
Discoveries always get me excited. Plus I was listening to archives of David Levy's radio program, specifically the interview with Doug Snyder who co-discovered 2002e2. It was nice to hear about someone hunting in the plane of the galaxy and hitting the jackpot, even though his 20" Obsession and Arizona skies are something I can only imagine using. He only had 70 hours in, too, lucky sod… :-)
Anyway – obviously both David Levy's show and Snyder's discovery are old news, but that's what happens when you take a couple years off. Snyder's discovery did give me hope in one respect, however, and that is to hunt the Milky Way. I used to avoid the galactic plane for the simple reason that it takes far too long to make verifications of fields against paper charts – there are simply too many stars. So a lot of hunters, myself included, used to avoid the dense star fields of the galaxy. As I'd hoped, the computer attached to the scope changes all of that.
I got set up in twilight and had a brief moment of panic when I wasn't getting power out to the telescope. Seems my cable is having a problem, and I'll need to have a look at it. However, I was able to get it to work long enough to save the session. Solving that little problem took up the time I was going to use to try for Sirius B, but the seeing was pretty bad anyway and it's a bit late in the season for that challenge. So I skipped that and went right into comet hunting.
I did the low west (horizon to about 45 degs altitude) for 2.5 hours, mostly picking up open clusters. I was wary because the best I could do on the alignment was 101, and that almost always means the az encoder is slipping someplace. I tried twice, same result, and so rather than take everything apart I just planned to sync on a lot of objects.
In general, this worked well, with the computer happily tracking my scope's position and making target identification a snap. I started off with M34 as the first open cluster of the evening, and over the course of the night I hit (in this order) 1528, M45, 1778, M38 & 1907, M37, 1647, M1, M35 & 2158 & IC 2157, 2266, 2186, 2420, 2269, 2355, 2301 and to finish M50. I also swept up Venus (nice half-phase), Mars and Saturn (didn't do a moon check). I probably could have had more open cluster on the list, if I'd have stopped on the looser examples, as it was I was only checking the smaller, tight examples, with the exception of the M objects. I also didn't really take any notes on these, and so technically their not observations per se. I just spotted, noted, and moved on.
About a half hour into the session I was joined by a fellow club member and his son, doing some Messier finding (I think they were working on the astro league list). I was impressed enough with the M35 region that I invited them for a look, though he (the dad) was far less sure of 2158 than I was. To me, 2158 was pretty obvious and IC 2157 was there but much less obvious. Are my deep sky eyes that good? Is it practice? I mean, 2158 is at mag 8.6/5', and IC2157 isn't much different 8.4/5' – these are not hard picks for an 8" in mag 6 skies. Are they? I'd like to see DSS photos of this region but the site seems broken at the moment.
I also noted what felt like a dark nebula right where Basel 4 is. It seemed in the eyepiece that the "normal" distribution of background stars was interrupted. Again I'd like to see a DSS image to be more certain of what I was looking at.
Had I not needed to get up the next morning, I'd have stayed longer. It was chilly but not cold, and I probably could have done another hour. The danger is pushing it too hard when I have an hour drive ahead of me. Glad that won't be an issue at the Farm.
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The sky broke up long enough in the afternoon/evening for the first real comet hunting session of the season. After reviewing the forecast in the afternoon and deciding it looked ok, I went and looked at what the surveys had been doing and made a loose plan to work the northern sky. LINEAR had not been doing much up above 60 degrees, except on the 8-hour line.
It's nice this time of year because I can get home from work, spend a little time with the family having a nice meal and then head out for a few hours before it gets too late. In the winter it's dark too soon, and later in the summer it means not even starting until 11 pm. I guess it's all a trade off.
I left home for Cheery Grove at a little before 7pm, arriving just after sunset. No evidence of my getting stuck was left, but I did see just how severe the drop was – very nasty. Won't be making that mistake again. The wind, however, had died off nicely and while the temp was dropping, too, it was still going to be a pleasant night. The temp dropped to about 30 by the time I'd finished the session.
Before leaving, I'd checked out the az encoder, to verify that it wasn't slipping. This was going to be the real test, the first with all the standard equipment together in hunting mode. Since I was down here in January with the computer, I'd traded using my daily laptop for an old Toshiba (233mhz) laptop that I configured with the specific purpose of being the scope computer. I doesn't have to be fancy or fast, just run SkyChart ok, which it does. And it's small – which is really nice – about half the size/weight of my Dell (it doesn't have an internal battery or CDRom, and it has a smaller screen, no trackpad, etc.). I've increased the mass of my stuff, but not the volume. In other words, I was able to get the all the stuff I needed for the laptop into the cases I already use for my gear.
I was able to set everything up in about 45 minutes, including a quick collimation. After doing that and waiting for the computer to boot I took a look at Jupiter high in the southeast. Seeing was ok but not great. It was funny because all the Galilean satellites were aligned on one side, and I had the thought that it was like a momma duck and her ducklings trekking across the sky. Yeah, it must be spring. :-)
After setting up the DSC, leveling, and picking the first star (Sirius), I locked onto the second star (Polaris), held my breath and pushed Enter. 100. Bingo! That's cool. I did a sync on Capella, then after turning the serial port on I turned my attention to the computer. I loaded the settings file I'd configured for the telescope tracking, and when I opened the scope connection I was rewarded with a nice viewfinder circle around Capella. Sweet. I swung the scope to M42 just to verify the computer was tracking, and there was my nice circle, happily following the scope through the sky. There it was, right there in black and red. It was about 8:50 at this point, not full dark yet but good enough, and so I began sweeping.
First pick of the night was to set the tone for a while, open cluster M37. Soon after was M36, NGC 1893, M38 and NGC1907. I swept up Mars in there somewhere, too (hi rovers). Most of these I was checking not because I thought they were comets but I was trying to see how well the computer/DSC combination was working properly. I sync'd on 1907, just to keep things nice and tight, and moved on. The area around M38 is pretty cool, and a very fine yellow star, (Phi (24) Aurigae, I think), just to the south in a nice field of white stars.
Confident that the computer was tracking ok (I could here the hard drive when the scope was moving – a nice audio reassurance that things are communicating), I moved the scope further north and into less dense fields. I checked on another cluster, NGC 1502, then kept going. About this time a plane passed trough my field, startling me (very bright all of the sudden). There was a fair bit of traffic out on the road, but with the hood over my head it wasn't bothering me too much. The eyepiece heater was also keeping up, but I was noticing halos around the brighter stars, telling of some very high, thin clouds around. With the naked eye I could see that Venus was also showing signs of this as well as it sank in the northwest.
I was sweeping 'high' – that is from about 30 degrees to 65 degrees above the horizon, and for this I was standing on a crate. From this site the north sky is obscured below that, but this was the zone I wanted anyway. Standing on a crate sucks, however, and I kept feeling like I was going to fall off.
Next up was the double cluster, NGC 869. Computer was tracking, DSC was tracking, I continued on. From there it was a rather dry deep sky zone for the next half hour or so. I was wanting an object to sync on, just to make sure the system was a close to accurate as possible. A couple of times I checked bright asterisms just to be sure.
First galaxy of the night was NGC 2655, a little pipsqueak at just over magnitude 11 (11.2 I think). It has a companion nearby that was under magnitude 12, but I could not pull that in. Swept on for a little bit longer, finally hitting another little galaxy, NGC 4589. That was a bit tougher at 11.8, and a new one for me.
With my fingers and especially toes cold, when 2 hours were up I called the comet hunting session. I did a quick swing over to Saturn for a moon count. It was in a busy field, but I noted Titan, Iapetus, Dione, Rhea, and Tethys. And with that, I called it a night and packed up.
All-in-all, the computer/DSC combination was fine asset, greatly speeding up the identification process and I was pleased with the result.
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It's been a pretty big day getting the web sites updated. The big piece was doing some more work on Eclipse Café, and adding some Venus transit information. I've been meaning to do that for some weeks, and finally got off my ass to do some research and put something together that is useful.
I like the Venus transit because as an event it has a direct lineage to Edmond Halley (aka – my scientific hero). It was ol' Eddie that discovered that one could use observations of the event, if timed accurately and widely space on the globe, to determine the scale of the solar system.
And, for once, I have proper gear for viewing the event, with the pronto and the solar filter I made. Even though I'm not going to travel for it, I'm hoping to catch the final hour or so of the transit from the Farm, where there is a fantastic view to the east horizon.
I also added some new expeditions to webExpeditions.net, which I normally wouldn’t mention except that one site has a collection of epic circumnavigations, including Cook's famous voyage to Tahiti to observe the Venus Transit of 1769. Neat stuff – the good captain's notes are in the above image.
Speaking of the Farm, I was up there last weekend working on the necessary and generally getting the place ready for summer. I did some cleaning up and more scouting – looking for places for tree houses and garlic plantations. I was itching for a dumpster to start loading garbage into.
I did make sure I could find my observing mark again, and while the weather was gorgeous, clear, cool, very dry, with the full moon I skipped bringing the telescopes. I thought about going for a walk, but I was dead tired after working all day. I hope that's not typical of the farm weekends (though it could be, especially this first season).
A couple weeks ago I added the ability to add comments to Jere's drawings on the Deep Sky site, but so far no one has. Oh well, seemed like a good idea at the time…
Can you tell this is plug day for tim's web development efforts? :-)
I did find and fix a bug in the discussion forums posts as well. When I moved over the old POF forums to the new message board I was having trouble with messages not sorting correctly, which I found and fixed, so now all the old posts are in their proper positions now. So there is the plus for AmAstroMB – had to work that in somehow.
Seriously, though, I am a web builder, and a lot of my efforts have been because I am a builder who likes astronomy. It is great to exercise graphic design as well as programming concepts with content I enjoy working with, even though it does end up consuming a lot of time. However, it's not likely that it would be time I’d otherwise be observing. Beats the hell out of watching TV.
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I was feeling kind of ill (still am actually), and while the sky was somewhat clear it was pretty hazy. Earlier in the week I'd hoped for some clear skies but all the evenings were foiled. Last night, my wife had an appointment so I'd not really planned to do any observing. It was warm, however, and while I was outside letting the dog back in (we're watching a friend's dog) I saw a nifty crescent moon nicely aligned with Venus.
So mustering what little energy I had left I gathered up the pup scope and the digital camera, got set up in the twilight and attempted a few pics. Actually, I shot a lot of photos, but with a digital camera it makes it a lot easier. I was once again smitten with getting a good crescent shot. I took a few shots of the sky with just the camera, then lined up the pup with the 30mm eyepiece and shot about 40 frames with eyepiece projection at all kinds of different settings. The result is up above. Not bad, but it wouldn't blow up for a damn. The seeing wasn't all that good for pictures (though it was pretty good for visual stuff).
Looking at the shots after the fact, visible is the terminator crossing a crater called Taruntius. In the photo it's just to the lower left of Mare Crisium. Barely visible in the photo above (but better in the original shots) is an unnamed peak way beyond the edge of the terminator that when I first started shooting was unlit. In the photo above there is one pixel visible for this peak, and by then end of my shoot it was connected to the "light zone". From Rukl's maps I can see the peak right off the end of Montes Secchi but it's hard to tell if its actually part of that range or not.
Once I was satisfied with my photos, or at least that I had done the best I could right then, I went in and fetched the kids out. We looked at the moon and Venus, and then I swung the scope over to Jupiter and cranked up the power to about 200x. That's where I could tell the seeing wasn't so good, but probably better than usual.
Even worse, however, is this POS mount that I put under this scope. This stupid celestron thing is the worst, and I mean WORST excuse for an alt/az mount ever devised (except for perhaps those mounts that come from department stores, but those don't even deserve to be called a mount). What a waste of $100. And what a way to cripple a nice refractor. *Something* needs to be done. I need to make a new mount or something. It was pretty frustrating trying to show the kids Jupiter with this thing vibrating all over the place and the inability to move it gently to keep something in the field. I should find a nice little eq mount. Or something.
Still waiting for a nice evening to try out the new comet hunting setup and see if I've got the DSC/Computer issues solved. In the meantime, I'm going to nurse my virus.
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