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Design/machining help needed
by John M. Craig 07 Sep '21

07 Sep '21

Hi Folks, I'm at least considering redoing the backplate (and perhaps mirror support) for my 10" RC Cass (whose spider and 2ndary holder I just replaced). Anyone interested in offering some design advice or know anyone who might be? Assuming I can come up with a decent design, will also need some machining done. Suggestions on where to go for that? Thanks for any advice you might have, John

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Free spider & Cass-type 2ndary holder
by John M. Craig 07 Sep '21

07 Sep '21

Hi Folks, I hope I'm not violating tradition or actual rules here, but I have some gear that I'm happy for someone to have if anyone could use it: A Novak spider with 2 attachment sockets at the end of each vane (so good for a heavy 2ndary). Vane diameter 11 13/16 " Vane width at hub 1 9/16" Mounting hole separation 1/2" Solid aluminum hub with concealed riveted vanes Hub accepts a 5/16 2ndary holder shaft The 2ndary holder is for a 4" diameter Cass-type 2ndary and has 3-point loosen/tighten type hex-head adjustments. Holder can accommodate large range of thicknesses of 2ndary (up to way thicker than seems reasonable--I used a fair amount of spacing material for my 1/2" thick 2ndary). If you're interested in either or both pieces, email me directly. I can send you pictures if you like. If pickup is impractical, I'm happy to arrange to mail it, but it'd be at your cost. If I don't hear back in a few days, I'll post it on CloudyNights. Ciao friends, John

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Great view of Jupiter last night
by John M. Craig 06 Sep '21

06 Sep '21

Hi Folks, I don't know what combination of things led to the amazing seeing last night up on the Nebo Loop, but Jupiter was particularly spectacular. I am quite sure I've never seen that much detail visually ever before--certainly not through my 6" so-called ED APO refractor. Saturn looked great too with it's retinue of Titan and it's medium-sized moons Dione, Tethys, Enceladus, & Rhea. I wish I'd known where to look for Mimas, it might have been visible too. For whatever reason, the seeing wasn't quite as stable just that much further west from Jupiter, but during moments of clarity, the Cassini division was clear and it was easy to see color bands on Saturn itself. We had the fun of having a local camp host drive up and when offered a look, hopped right out of his car and joined us for the rest of the session. Over the years I've noticed that there are relatively few people who will approach and ask what you are looking at or some other leading question--hoping you'll invite them to take a look. But, when people are offered, they're often quite enthusiastic. One recent time we were up there on Nebo Loop at the Beaver Dam Overlook (a great spot with the only light dome being to the west and northwest) the folks who came and looked after we offered game several of us papayas--I promptly forgot about the one I'd be given and since I didn't unload the gear from the van right away, it had turned into a sticky mess in the heat. Oops. Good viewing all! John

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Another good day for H-alpha solar viewing
by John M. Craig 31 Aug '21

31 Aug '21

Hi Folks, Looks like there's more prominences today than in a long time. The large, involved active region 12860 is approaching the limb where it should lead to some interesting prominences too. There's two other active regions that have numbered designations on the near side and a slew of them on the far side. Sorry I don't have any white-light experience to report, but if it doesn't start raining or get totally clouded out, it'd be a good day to take a look. Tomorrow should be good also. Sol is definitely waking up! John

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Some great sunspot activity today
by John M. Craig 27 Aug '21

27 Aug '21

Hi All, Whether you have a white-light solar filter or an H-alpha scope, take a look at the sun today, if you have a chance. There's a huge complex group of sunspots. At the moment there's also an amazing plume of a prominence but it seems to have faded somewhat. I haven't seen anything that far out from the limb in a long time. Got an informal star party going tonight up at the top of the Provo Canyon South Fork Road. We'll see how many people show up. Last time I invited maybe 30 people and ended up observing all by myself. But, that's fun too, of course. Happy watching!

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Recurrent nova RS Ophichi in outburst
by John M. Craig 13 Aug '21

13 Aug '21

Hi Folks, Wanted to get in a separate subject heading for this so didn't include it in earlier email. I wasn't able to find it Wednesday night when I was out for the Jupiter moon show. https://skyandtelescope.org/astronomy-news/recurrent-nova-rs-ophiuchi-just-… It apparently faded fast the last time it popped off. But it was bright enough to be visible naked eye, if you had good dark skies in that direction. Interestingly enough, on my somewhat impractically large Sky Atlas 2000.0, it's plotted as N1967. I don't know if that was it's first official outburst, but no indication of recurrence. Sky Safari Pro has RS Oph as a searchable object and lists its coordinates as: RA (2021.6) 17h 51m 22.09s DEC (2021.6)-06* 42' 49.6" I'd be interested to hear if you see it as it fades. John

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Anyone else see the fun w/ Jupiter's moons on Wed night?
by John M. Craig 13 Aug '21

13 Aug '21

I should perhaps have put a notice about this before it happened--sorry about that... For a good while before 11 pm on Wednesday night, only Jupiter's most distant Galilean moon, Calisto, was visible--or at least obvious (Ganymede and Io were occulted and Europa was transiting--I didn't have clear enough seeing or a big enough aperture to see Europa against the planet). Within about 7 minutes all 3 became visible as they appeared next to the limb of the planet. It was really fun to see. The amazing thing was that I've never seen any of the moons look anything but star-like (even in my best scopes--need to get the 10" RC Cass fixed up and working again). But with them right close to the limb of Jupiter, I was seeing them as disks at 125x with my low-budget 4" C102 achromat. Most unexpected! I think it may be a question of contrast--when they're distant from Jupiter, against the black of open space, my eyes (at least) do not see their disks: they look like bright stars. But as Ganymede and then Io emerged on one side (right close to each other almost in line with the N equatorial belt) you could definitely see that it took a fair amount of time before they became separated from the planet and then it was easy to see that Ganymede was substantially larger. Same effect with Europa: a bump on the limb, then a bigger bump, and finally a tiny disk. Amazing! Both my wife and daughter (not experienced observers) saw the moons as disks too. All this from my front yard--which is about as light polluted as it gets: we have one of the stupid acorn-style street lights just across from us and Orem is all Bortle Class 5 or worse. Hurray for bright things to see! I'm going to have to watch for times when the moons reappear from occultation and transit and check them out again. John

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Well, maybe I should have actually gone outside...
by John M. Craig 26 May '21

26 May '21

Well, after reporting that the eclipse was clouded out, 2 near neighbors saw it--with some wispy clouds apparently, but perfectly visible. (Well, just got back a couple of days ago from moving a daughter back home from Seattle--so apparently I wasn't exactly in prime viewing state--when I looked out the window, I couldn't see anything. A guy who lives just east of me says he saw the whole thing! A work colleague who lives about a mile SE of me also saw it. So, I guess I just didn't look hard enough. John

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Anyone see the eclipse? Good sunspots today
by John M. Craig 26 May '21

26 May '21

Hi Folks, The eclipse was clouded out here. Anyone see it? There's some quite involved sunspots today. Best I've seen this solar cycle--although I was traveling w/o a scope over the last few days so they may have been better then. At any rate, catch 'em before they rotate around to the far side. Hoping for some clear nights! John

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Action on the sun
by John M. Craig 12 May '21

12 May '21

Hi Folks, Kinda late in the day to be mentioning it, but some good hydrogen-alpha light activity on the sun and one big enough sunspot that it's probably worth a look in white light (haven't done that myself). According to www.raben.com/maps, there's actually 2 active regions on the near side. I will have to look more carefully tomorrow. There were some good prominences late this afternoon also. So, if you have the gear, probably worth a look tomorrow. (The weather has been really frustrating: clear during the day but nothing going on with the sun; cloudy in the evening. But hoping to spot Mercury during this apparition and perhaps see the barely-past-new moon tomorrow evening.) I need to drag out and see the Cassiopeia nova in the morning. I saw it last month when it was at about magnitude 8.2; apparently it's brightened yet again. Happy observing! John

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