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8/08/2015

Lazy Susan Mod for the Orion XT10 Azimuth Motions



     All I have to say is why didn't I do this YEARS ago! I just gave a 6 year scope that hasn't really been used in say well over 4 years except for outreach and occasionally at home. A long time ago I added from Tony C. at Astronomy-Shopper (LINK) his Scope Grips.  They were a MAJOR improvement in the altitude system for my Orion XT10.  I could loosen or tighten the knobs to increase or decrease tension depending on my eyepiece. To be honest, I found a position for the eyepieces I used and left it there for my observing session. I may have to make one adjustment just to tighten later that night. I highly recommend them if you have a stock Orion XT dob. I also got Tony's Scope Totes (FYI, I don't get anything from Tony I am just sharing info) which you can see both in my video and at this LINK.  There are cheaper alternatives like the Strap Handle LINK  or over at Home Depot (also Lowes) is the Velcro Hand Strap Handle LINK.  I like that the Astronomy Shoppe Scope Totes fit my OTA and they make it so much easier to life. I find that after a year of losing 80lbs and working out four times a week, that the 10" is not heavy to lift at all. It is just awkward and the Scope Totes make it easier to life.  

     Now the only real issue I have never liked on my Orion XT10 are the azimuth motions. I didn't mind the stiction I guess when I didn't know any better, but my 14", 17.5" and 24" have made me realize and adore buttery smooth motions. I have read before about adding a Lazy Susan bearing to the XT10 LINK and I finally after an evening of outreach about 2 weeks ago, decided to give it a try. The worst thing that could happen was I had to remove the Lazy Susan, have four holes in the bottom of the base board and return to the current method.

     Well, I ordered a 12" Lazy Susan bearing since I could not find one locally and it arrived earlier this week. I went to Lowes today and got both some #8 screws in the 1/2" size to mount the Lazy Susan on to my base board.  I had extra carpet so I cut about 1"x1" strips and flayed off any carpet that might want to come off (so they don't go into the bearings and mess this up) and used black electrical tape to secure them. I am sure I will have to adjust that later but that is fine.

     To get started I took the base apart, something I have done quite often trying to improve the motions in azimuth and then took the bottom base (some put the Lazy Susan coming down on top of the base; I went this way as I was thinking that if I had it come down and facing down, it might be easier to get dirt into it but on re-thinking it, it shouldn't. I did it this way as it made sense to me as if I was actually installing a Lazy Susan in my wife's cabinets.  Anyway I WISH, I really WISH I had filmed me measuring out my two lines, each intersecting the middle of the hole in the board. With those lines drawn, I measured the inside diameter of the Lazy Susan, the open part, and then measured using a caliber and a compass the exact location where the Lazy Susan should be. I then used a punch to make a slight hole in the center of where the Lazy Susan would attach, removed the Lazy Susan to my bench to protect it from dust and drilled, using a bit smaller then the diameter of the screws I was using (#8 1/2 inch) to start the screw.  I then changed the bit out, put in my bit into the drill, laid the Lazy Susan back on the base, lined it up perfectly and screwed down the screws securing the Lazy Susan!  My next step was to put the carpet down to act as breaks, (I put one down behind each teflon pad, one isn't in place yet in the picture) which they do nicely and as you can see in the two pictures.

   


     I now reassembled the base by putting the bolt back in and securing it, and then putting some a smooth nylon washer down on top of the bolt (where it would stick through in these images) and then I put 5 Milk Jug Washers here to further help both the motions and to break it. I did leave the Teflon pads on as when I got done the pads were still well below the base.  Last I secured a washer down and then another nylon washer and Milk Jug Washer (My nylon washer replaced his rubber washer in the link I posted above) and then secure the bolt down.  

     When done, I wasn't sure how much I was going to have to play with as I assumed it would take assemble and reassemble several times to get the stiction and motions right where I wanted them. I keep the XT10 in a bag my wife gave to me one Christmas to store it, and pulled out the tube.  I put the modified base out in the grass in my front yards because I had a good 10 mph wind/breeze going with gusts to around 14 to 15 mph, and I wanted to test it out. After putting the OTA on the modified base I moved it and BOOM! Perfect!!!!! I let the scope take the breeze from the southwest full across the tube to see if it would move, and it didn't.  

     I next moved it back to the garage and decided I better film this and I did do.  I have to say that I am REALLY excited about this 10".  Good mirror in it now, good motions, it is my go to for outreach (allowing me to keep the 14" and 17.5" for observing) and to let young people learn on it. I agree that I will probably have to exchange the Lazy Susan every couple of years but at $12 to $20 shipped, not an issue. I also now have a decision to do in the backyard. Refractor which I love or 10" reflector? I think the old XT10 has a new life and all from a simple mod that honestly took about 1 hour to do.  If you want to improve your motions look over the links and my notes, shoot me a line and if your local, I will be happy to help you (but it is your decision so don't get mad at me if something doesn't work right!).  You will see in the video I have the 17" set up in the garage as I had to exchange out the Milk Jug Washers on the secondary and do a few more mods (always a work in progress and I have learned to really like to tinker with my scopes).  Here is the video I did in my garage after setting back in there. Again, easy mod to do, and I'll keep you posted if for some reason it goes south but I don't see any reason for that to happen. 





NGC 7252 Atom for Peace Merging Galaxies ARP 226


    


From: "NGC 7252" by ESO - http://www.eso.org/public/images/eso1044a/. Licensed under CC BY 4.0 via Wikimedia Commons - https://commons.wikimedia.org/wiki/File:NGC_7252.jpg#/media/File:NGC_7252.jpg


   This galaxy is known in the amateur community, yet I cannot find that many images of it and I find no sketch of it. At blue magnitude 12.6 (12.7 in some catalogs) and a visual magnitude of 11.7 and a surface brightness of 12.8 it should be able to be seen and sketched. How much is visible I do not know since I have never captured this galaxy.  I would be greatly amiss though if I did not mention Jimi Lowrey's observations of this object over at the Deep Sky Forum at this LINK.  He has observed this peculiar galaxy "many times over the years" and his post there breaks down some of the more challenging visual parts to go after. I encourage you to look at that post. Jimi mentions in article on this object (it is a very well studied professional object) and which is at the top of this list of articles if your so incline to study/read up on the professional papers of an object you like to observe (I do) LINK (arxiv search results). It gets its name from a speech that then President Eisenhower gave in December of 1953 called the "Atoms for Peace Speech."  There President Eisenhower called for peaceful uses of nuclear power and this galaxy, in images looks like an electron going around the nucleus of an atom so it was named after that speech.

     Jimi points out in his article and Wikipedia does as well that in a paper published about  NGC 7252 "In August 2013, F. Schweizer and others published a paper in the Astrophysical Journal titled "The [O III] Nebula of the Merger Remnant NGC 7252: A Likely Faint Ionization Echo."  This reports the finding of a Voorwerpje on the outskirts of the well-studied NGC 7252." LINK to article. I and see the Wikipedia article  LINK.  If you go to Jimi's post he has a finder chart there for the Voorwerpje in NGC 7252 and a massive star cluster, W-3 which is over a hundred times more massive than our globular clusters and may be the remnant of a galaxy core from an earlier merger.

     This object gets even cooler I believe. In 1993 using the Hubble Space Telescope, this team of astronomers,  Dr. Bradley Whitmore of the Space Telescope Science Institute (STScI) in Baltimore, Maryland and Dr. Francois Schweizer of the Carnegie Institution of Washington. Co-investigators in the Hubble findings are Drs. Claus Leitherer, Kirk Borne, and Carmelle Robert of STScI. Dr. Schweizer's co-worker in the Hale Telescope research is Dr. Patrick Seitzer of the University of Michigan at Ann Arbor. discovered several key things about this galaxy.

     Here are their findings summed up from the NASA article at this LINK by  Dr. Bradley Whitmore:

     "I knew we had a major result within 10 seconds of looking at the Hubble picture," said Whitmore. "This may provide a clue to how all globular clusters formed." He added, "The Hubble observation also shows how tiny, disk-like structures may have formed near the centers of many other galaxies."
The striking image shows a spiral pattern at the galaxy's core, which is surrounded by bright star clusters.
The Hubble observations succeeded in resolving the globular clusters, that is, measuring their apparent sizes on the sky despite the vast distance of NGC 7252. The galaxy is 300 million light- years from the Earth, and located in the constellation Aquarius.
The clusters are typically about 0.04 arc seconds in diameter, which corresponds to the apparent size of a dime, seen from a distance of 60 miles. This means that the clusters are each about 60 light-years in diameter, the same size as the globular star clusters of our own Milky Way."

     Furthermore, though we won't see this visually, it is a cool feature of this galaxy (from the merger 1 billion years ago) that  "the pinwheel structure found in the Hubble observations of the central disk of NGC 7252 consists of a system of interstellar gas and stars, orbiting the bright nucleus of NGC 7252. The gas and stars in the disk look like the swirling pattern formed by cream just mixed into a cup of coffee."  Here is an image of that pinwheel shape (you'll see it in the Wikipeida article but the visual view in that article is down lower):



   

     Perhaps one of the main reasons NGC 7252 is significant and this paper was back twenty-two years ago, is the fact that it shows that merging spiral galaxies can form into ellipticals and form new and thus have more globular clusters in them.  It reinforces the notion of where we get elliptical galaxies from. From a visual standpoint Dr. Whitmore states "If the globular clusters in the Milky Way were as bright as the newly found clusters in NGC 7252, many of them would be brighter than the stars in the Big Dipper, and readily visible to the naked eye." Now that would be cool!

     So with this object my goals would be to observe the tidal tails here, evidence of the merger of two galaxies.  Jimi states they are hard to see and I am sure they are, but I'll give it a go in the 17.5" and the 24" just to see if I can.  The next item or object would be a little Voorwerpje and the super cluster of stars called M-3.  Here is the Hubble image from above labeled and you can go to Jimi's post at Deep Sky Forum (above link) to see his rendering.



     In truth though, unlike that fine Hubble image, I expect the galaxy at magnification to look rather like the first image, or perhaps, even more realistically the second image.





     So how do you get to this object? Rather easy.  I have included a basic finder chart here and it is in the constellation of Aquarius.  Good luck and I'll be reporting my findings and I hope you share yours. Remember to enjoy the wonders of the sky!





     Edit:  I left off two links to sites that pertain to items in this galaxy that I think some may enjoy. The first is to Galaxy Zoo's forum where they discuss the Voorwerpje  at this LINK.  Great images there of the Voorwerpie.  This is a direct LINK to a pdf/power point done in NGC 7252 by Dr.  F. Schweizer and I recommend it if your into the scientific explanations behind objects you observe. Wonderful object and it will be a blast now that I have studied it to observe it, see what I can observe, document it via sketching and share.