I’ve decided to just call M27 the Apple Core Nebula. It’s also known as TNFKATDN or “The Nebula Formerly Known As The Dumbbell Nebula”. It was a pretty nice night, though cold, until about 11, when wispy clouds started to mess up the view. I spent a while earlier seeing if I could gather images with my DSI which could be used for asteroid hunting, but came to the conclusion that with my setup, that’s not going to be possible. Anyway, at least I got one good image tonight…
November 20, 2009
November 16, 2009
M33-Pinwheel Galaxy on 11/15/09
Tonight, I visually observed a number of targets and finished up what I need to get my Messier Award from the Astronomical League (through my club, the Barnard Astronomical Society). As a result I just had time to image one thing and I chose M33, the Triangulum or Pinwheel Galaxy. It's a nearby galaxy (in the local group) and you can find more here.
November 8, 2009
C20-North American Nebula (NGC7000) on 11-7-09
This was my first attempt at the North American Nebula, also known as C20 or NGC7000. If you look at the image sideways, it sort of looks like the gulf of mexico – actually other images by other people show the shape more completely (plus this is just a part of it – it’s a big nebula!). This was also the first time I tried using a red filtered image added to the full color images. I stacked a bit more than an hour’s worth of RGB from my D50 and then did 36 minutes having added a Red filter on top of the Orion Skyglow Imaging Filter I use. (I recently got a bunch of 48mm filters off of eBay cheaply, this was one of them) After stacking the red images, I added it as a screen over the regular image and it really made the image pop – it’s a bit like a cheapo Hydrogen Alpha filter, combining the two filters. Anyway, I’m pretty happy with how it turned out – the only problem being that the red images didn’t align very well with the RGB image (thus the sort of letterbox formatting).
November 2, 2009
Hunter’s Moon on 11/1/09
Technically, the moon will be full around 2:00pm tomorrow, but it won’t rise until sunset, so we won’t be able to see it when it’s actually full, so this is pretty close. Tonight’s sky was clear, with low humidity, and if it weren’t for the big, bright moon, I’d have images of other stuff, but the Moon really washed everything out.
October 28, 2009
M27-Dumbbell Nebula on 10/28/09
Tonight was mostly clear, with occasional wispy clouds. I decided just to focus on one thing with my D50 and choose the Dumbbell Nebula – M27. M27 is a planetary nebula (which has nothing to do with planets) which is the remnants of a star that exploded. You can see the star if you zoom in – it’s the cyan one in the center of the nebula. The huge number of stars in this image is from the location of this nebula inside the Milky Way. The Dumbell Nebula (or Apple Core Nebula as I refer to it) is an easy to find and easy to see target in the fall night sky.
October 20, 2009
M13-Great Hercules Cluster on 10/19/09
In addition to the Sculptor galaxy, I also took some images of M13 – the Great Globular Cluster in Hercules. It’s one of my favorite targets visually and with the DSI-II camera. This one shows it in context and inclues a small spiral galaxy in the upper right that’s visible if you zoom in to the large version. Overall a really nice night.
C65-Sculptor Galaxy on 10/19/09
Tonight was as nice as last night, but again, quite cold. I decided to do some more wide-field imaging with my Nikon D50 using the 2″ Orion SkyGlow Imaging Filter that I got a while back. I think it does a good job of lowering the overall sky noise that I’ve seen, particularly with this camera. I love wide field shots because they show context and this one is no exception to that. The Sculptor Galaxy fills my DSI-II camera almost completely and is neat to image with that, but it’s also neat to see the context of this galaxy.
October 19, 2009
M31-The Andromeda Galaxy on 10/18/09
It was very cold this evening, but the sky was clear and so I finally had a chance to try out my new imaging filter with my Nikon D50 camera. I decided to image the Andromeda Galaxy, M31 and I think it did a good job. I need to take some good flats to get the levelling right, but overall, I’m pretty pleased with the image.
October 18, 2009
Participate in the Great Worldwide Star Count!
Well, I’m a bit late in promoting this – it ends on the 23rd, but it’s time for the Great Worldwide Star Count again! Last year, and two years ago, my kids and I participated in the Great Worldwide Star count. It was fun and educational for the kids to observe how many stars they were able to see from our yard and our observations helped the cause of Science!
This year’s star count is from October 9 – 23. We’re going to be doing it again tonight and would highly recommend participating to everyone. If you are interested, go here to find out more. It’s easy, takes only about a half an hour and benefits science. Your observations are put together with others in order to create detailed light polution maps.
The reason I haven’t done it sooner is that we’ve had clouds for weeks. I wasn’t even sure we were going to have a chance to do it at all until today. It looks like it’ll be chilly, but clear this evening.
Update: My kids and I determined that we had magnitude 6 skies – very, very good – especially for a neighborhood.
October 17, 2009
Project: Adding a Motorized Focuser to My LXD-75
A bit over a year ago, I bought a Meade 1244 motorized focuser unit and adapted it for use with my LXD-75 SN-8 telescope. The 1244 unit (that I got off of eBay) is designed for a completely different scope (the ETX series), but I was convinced I could make it work with my stuff and so I got one cheap. As far as I know, there is no model specifically designed for my scope. Here’s how I did the adaptation:
Adapting the focuser shaft
After disassembling my focuser, I unscrewed the left knob from the shaft. After measuring the threads on that side of the shaft, I tapped a brass rod that I had cut to length (about an inch and a quarter) so that I could thread it onto the shaft. Once I made sure that it screwed on well, I added some Loctite Blue and screwed it in. I don’t expect it to ever come apart, but if it did, it’ll be easy for me to reattach it. I also flattened one area on the rod so that a gear set screw will have a place to hold on.
Now that I have finished the rod, I need to attach the gear that came with the 1244 focuser. The rod that I purchased had the same outer diameter as the inside of this gear. I can’t tell you what it was because I don’t remember, but I just took the gear to the hardware store and found a rod that fit nicely. Before attaching the gear, you have to slide on a plastic piece that came with the focuser first. make sure you have it facing the right way. You can spin it around, but you can’t flip it once it’s on there. After sliding the plastic piece on, I slid on the gear and then tightened the set screw. Incidentally, you’ll need a .050 hex wrench to tighten it. The 1244 comes with one.
Reassembling the focuser
Now that the shaft is complete, it’s time to reassemble the focuser. You might take this time while everything is disassembled to clean out the grease and gunk and relubricate the focuser. I added a bit of teflon tape to cut down a bit on focuser shift and I used a light coating of white lithium grease to relube everything. Next I place the focuser shaft into position:
Next, I added the cover over the “gearbox” area.
Before I put the screws on, I add the custom bracket that I made. I made the bracket from a piece of aluminum that I carefully cut to size, bent and then drilled 5 holes. To make sure the holes were in the right place, I drilled through the gearbox cover so that the four screwholes would match up. The other hole, for mounting the focuser, I marked through the screwhole in the focuser with a pencil lead (it’s pretty thin) and then drilled. Here’s the custom bracket:
While you hold the bracket in place, you screw in the four screws through the bracket and the gearbox cover into the focuser. While I start to screw them in with my cordless drill, it’s important not to tighten them too much, so I finish by hand. As you tighten them, you make it more difficult to turn the gear and it presses harder on the focuser tube. You want the movement to be nearly effortless, so make sure you test as you tighten by hand.
Attaching the Motor
It’s now time to attach the motor. I place it over the shaft and slide it into place on the plastic piece under the gear.
Next, I drop the screw into the focuser screwhole and through the custom bracket and I tighten it very tightly with a nut on the bottom.
Now, the next time I’m out, I just plug in the focuser’s cord into the auxiliary port on my telescope and I can control it with my Autostar 497 hand controller or if I’m hooked up to my laptop, with my software.
Having the electric focuser allows me much more precision in focusing and makes it easy for me to focus without touching the telescope. It now means the knob on the other side is nearly useless (though I can look at it and see if it’s turning) because you can’t turn the shaft except with the motor now. Of course, I’m always plugged in with this scope, so it’s not a big loss and if it ever broke I could just unattach it and use it manually again. I’m planning on someday in the future replacing the focuser with a much nicer one (the stock SN-8 focuser is not very good), but until that day I’ve got a much better system. Over the past year as I’ve used this, it’s really been fantastic and I’ve become almost addicted to electric focus. It’ll be hard to do without if a future focuser doesn’t have that option.
