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Posts Tagged ‘Porrima’

The Explore Scientific  127mm f/7.5 Air-Spaced Triplet ED Apo arrived today.  I should quickly add that  at $1700 (NEAFF sale price) I don’t believe it’s a true APO – but in a word, it is good – very good. In fact I suspect this will become the scope I use the most.

I need more experience with it, of course, but I was impressed with the build and with a 10-day-old  moon and better than  average seeing -transparency was  below average – well, I’m going to wear out the word “wow” – I’m also well on my way to becoming a confirmed refractor addict.

The ES 127? Worth every penny! The only way I could go for a longer focal length than this would be with an entirely new pier and mount.  And at this point I certainly don’t see the  need for it. Other refractor fans will not be surprised, – you’ve been there.  But I can’t remember when I’ve enjoyed this hobby more.  Some highlights of the first 90 minutes witht he ES 127  and that 10-day old moon over my shoulder –

1. Double- double – I have never seen it this way. Period. Oh I have split it very cleanly more times than I can count – but never like this. I cranked it up  to 381X with a 2.5 Nagler. Just incredible. With the same eyepiece the 80mm Lomo triplet was giving a good account of itself, of course, at 192X.  And the best framing in the five inch came with the 3.5 Nagler – 272X. And while I’m thinking about it – both scopes balanced beautifully on the UA DoubleStar.  I could even take the eyepieces out of both telescope – switch from 2.5 to 3.5 in the 127 – and still have the target in my fov – no slippage whatsoever. That’s good for a double mount.

2. Porrima – at last! I won’t kid you. it wasn’t like the double double – but there was plenty of clean black sky between them, though so much light they still fought with one another as they rolled across the fov. Here the full 381X was needed to get a really clean break – and I suspect I will find another night with better conditions – but this was delightful. In the 80mm i could not come close to separating them – they just waltzed across the field  – hinting at the existence of two bodies – but no space between them.

3. Saturn – four moons leaped out at me – I don’t know how many I should have seen – and this was over in the stronger moonlight.  But here the quality of the seeing really showed that it was not perfect – good, but room for improvement –  because Saturn could not take the magnification without  deteriorating. Even at that, i don’t recall a better view except one night of exceptinal seeing with the 15-inch when  Bob and Mark were here and Mark kept digging into his eyepiece case for shorter focal lengths. We had the 15 cranked up past 500. So there’s something to look forward to here.

4. Polaris – just charming, especially with the moonlight trying  – but unable – to wash out its companion.

5. M57 – now this awed me! Just a wonderful view under poor conditions. Here’s where I’m starting to think there’s no need for more light grasp to satisfy me.

6. M13 – again, very nice considering the intensity of the Moon, though it was lower in the west by this time.

If I can stay awake  – and transparency improves – I may go out after the moon sets.

Bottom line – I have lots of good things to say about this scope. I also have some quibbles, but minor. It will take a while to sort them out – but the 80/127 on the doublestar looks like my ideal observing set up – we’ll see how it stands the test of time.

Don’t think this means the Unitron will get ignored. When I have visitors I’ll let them use the 80/127 and the SCTs – I’ll use the Unitron  and other classic scopes.  AThere’s something to be said for honing your skills by using smaller scopes – sort of like as a kid when I learned to hunt with a single shot .22. My one issue with the 127 is they put  a straight through finder on it and though very nice, it just ain’t going to work for me when pointing much above 45 degrees -so I’ll swap it with a RA one off of one of the SCTs.  Of course on the DoubleStar mount my 80mm becomes the primary “finder.”

I got out again just before 4 am which gave me about half an hour of dark skies – so I did a very quick deep sky tour starting with M51 – could see it well – certanily enough to satisfy me and no challenge at all as it is in the 60mm.

M3 was disappointing and when I went to Izar I saw that part of the reason was the seeing – it came way down from what I had at 1 am. I would say at 1 am it was a 4, at 4 am a 2 on a scale where 5 is best – still, I could use close to 200X and could split Izar, but it was sloppy.

What was exquisite – just the  kind of view you would kill for – was Omicron1 Cygni. I thought the scope would overpower it, but oh my – the colors were what I imagine a fine wine is to a wine fancier – the primary was just screaming orange  – and the blue star was making a statement as well – but the killer was the green one – just the delicate of pastels.

But I get ahead of the tour – I went to M5 and found it much more satisfying than M3.

M11 was fabulous – which tells me that this scope is going to eat up open clusters.  (A large part of the charm of Omicron1 came from the black sky and loads of pinpoint stars in that neighborhood.)

M27 did well with just a hint of interior stars – if I had stayed longer I’m sure i would have seen more. Same with with M57.  The Double Double split, but not nearly so nicely in the poor seeing as it did earlier. Polaris did well, too – and Mizar – again, i thought this would overpower it, but with a 13mm Nagler it was fabulous – 73X.

So what next? Well, the 80mm F15 Towa 339 arrived today to round out the new/old scope binge. But my goal now is to start selling stuff – none of the refractors, of course. But I probably will part with a SCT. For personal viewing I could be very happy with the Unitron 114, the 80/127 rig, the C8 – and yes, the Obsession 15 for galaxy hunting. (OK, so who wouldn’t be. I’m damned lucky, but there are no computers, no electronic motors, no imaging gear and I’ve been waiting many years to get to this point  😆  I’ll keep the LX50 and I’ll see  where the Towa fits in with this mix. Folks coming over tonight, but I’ll give it a try. Meanwhile, off to Astronomy Day!

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That was my “eureka” moment this morning as I got reacquainted with M10, M12, M5, M3, M13, and M92 in that order.  I felt real good about it too – until I came in and started rereading Stephen O’Meara’s descriptions in “The Messier Objects” and realized how much I didn’t see 🙂

But in another thread Bob was talking about “getting your mind around what you see” and that’s just about always my main goal and this morning I started by comparing M10 and M12  as they appeared in the C8 at 154X (13mm Nagler). I was noticing some details, such as the small triangle of brighter stars that partially engulfs M12  and how the layer of resolved stars over its core was greater in M10. Suddenly a description I had read popped into my head – one of these globulars was likened to a “gumball machine.” The author was referring to the colors of the resolved stars – only which one was she talking about? At this point I thought it was something Sue French had written, but I couldn’t remember if she was talking about M10 or M12, so I set out to determine which it was that looked more like a gumball machine.

The more I compared the two, the more I appreciated their individuality – but I was darned if I could detect much evidence of color in either.  Still, i decided she must have been talking about M10. And that’s when I had the “aha” moment that lasted and lasted . . .  Suddenly  my mind’s eyes was turning the different layers of stars into one of those snow globes you shake – or maybe more a series of crystal celestial spheres like those woodcuts from the MIddle Ages show. Whatever it was, the gumball metaphor has caused a break through and each globular now looked like what I knew it was – a three dimensional globe of hundreds of thousands of stars. Of course we can’t see 3-D at these distances and with one eye – but the impression was overwhelming and I tried to hold it like you do a dream, knowing if you look too closely it will vanish.

I love to tour the globulars available at this sidereal hour (c. 15h) and so I set out northward for M5. It was a “wow” making  M10 and M12 look pale in comparison. And the 3-D magic was, if anything, enhanced.  I moved on to M3, one I have visited many times in recent months as it was rising on winter mornings. Hmmmm… not as nice as I remembered. I mean cool – but M5 seemed to blow it away. OK, how about the “Great Pumpkin” – the  one everyone knows, M13? it was just about at the zenith and at this point the C8 corrector was collecting a little dew ( probably had something to do with the performance of M3, though I’m not sure.) It was quickly dispersed with  the hair dryer and I warmed up my hands a bit in the process. OK – M13 deserves its rep. I know some observers think M5 is better, but I have to go with M13 – not only because it gets higher in our sky ( which helps) but  because with the same scope and eyepiece you resolve so many more stars and the 3-D impact was overwhelming.  I wanted to look for the galaxy that’s near it, but I couldn’t remember exactly where it was and I didn’t want to break the spell by checking my charts. I was on a roll 😉

So where next? M92, of course, the most under-rated globular in our sky. M92 makes you appreciate that small can be beautiful too.  If M13 is the Great Pumpklin, then M92 is an apple – hard, crisp and bright like a Red Delicious! The 3-D vision held. Hope I can regain it another night!

When I got in I immediately checked Sue’s book to see if the gumball machine was M10 or M12. Ooops – she doesn’t use that metaphor. So i went to Stephen O’Meara. Yep. There it was – and he was talking about M12, not M10 as I thought. But no matter – the remembered phrase triggered that wonderful sensation of a third dimension. And rereading his description I know I have to slow down and spend a lot more time with these old friends over the next few months, for there’s so much more to see in each of them.

I’d started the session, btw, by checking on Porrima and for the first time getting a clean split with the C8 at 286X – but I was disappointed. This pair so bright and the C8 so sloppy ( I probably still don’t have it as well collimated as it should be) that there just was a lot of light in the diffraction rings – far too much. At this point I really missed not having something like a 120 or 127mm apochromatic. The split just isn’t wide enough yet for the 80 to handle – maybe next year.

Oh – and my other revelation of the night? I can’t reheat my tea with the hairdryer! Well, not in 10 seconds, anyway.  Another brilliant idea proven dumb  🙄

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I find I tend to get drawn into M42 and ignore a lot of the other neat stuff in Orion, so last night (2/11/10) I went out early to look for some double stars – no luck – 70 percent clouds – though the stuff over Orion was thin. Looked again around 8:30 pm and it was still at least 50% clouds, but Orion was entirely in the clear. So I hunted down some stars I’ve previously ignored, starting with  Iota Orionis and its companion double ∑747. Both showed easily in the 8-inch, LX50 with a 24mm Panoptic.

(BTW – this is a real neat SCT I picked up for $300 complete with working mount, equatorial wedge, tripod, and several extras. I think part of the reason for the price was the mirror was starting to develop some unidentified lifeforms. These looked scary, but I  saw them once before on an LX90 I then owned and when I sent that scope back to Meade for motor repair, it also returned with a clean primary mirror. Can’t be magic – so I figured there must be some way to clean them and if I had to I could break the scope into parts, sell the parts, and make my money back and then some.  But that was before I thought about contacting Pete to see if he had some suggestions – he sure did! He not only showed me how to do it,  but did the job. That was great because up until then I had never even dared remove the  correction plate from a SCT!  These things look more scary than they are.  Hey Pete – thanks again – terrific views!)

Anyway, back to Iota. Sissy Haas, in her book “double stars for small telescopes” calls this a “pair with fantastic contrast.” I wasn’t that overwhelmed, though I did like it. Double stars take a while to grow on me.  But I sketched the field, moving up to a 13mm Nagler. With that I could put Iota and companion in the center of the field and ∑747 still appeared at one edge. At 4.7 and 5.5 these two white stars were the brightest in the field besides Iota and so widely split I would not have thought of them as double if I hadn’t read about them in advance.  This is one of those fields I’d like to study with a much smaller scope like the 50mm refractor that should arrive in a week or so  – hmmm. . . or that $45, 76mm baby DOB from Celestron which may arrive this weekend – I think it would be much more appealing. But its good to get to know this way. What was most interesting was when I got inside later and checked a Sue French piece in “Celestial Sampler”  on other stuff around M42, I found  she identified Iota as a triple! She said there was a third star to the ESE of the primary – split by 50 seconds and at 9.7 the faintest of the three. I checked my drawing and sure enough – I had put a faint dot at just the right point. So I saw it – but honestly, I would never have associated it with Iota – it was just one more star in a fairly rich field. But that will make Iota a real challenge for the small scopes.

My second project was the quadruple star, Lambda, in what I think of as Orion’s head. The problem here was quite different. I had screwed up when filling out my double star logging form and put down the wrong position angle for each component. I didn’t notice at first because the first component had a PA  close to the mistaken value.  So I identified it and  because I had the separations down correctly, I figured out the other two as it began to dawn on me that I had the wrong position angle data. When I got in the house and checked my drawings against the correct data in the Haas book I had recorded all four stars correctly. Again, these were no challenge for the 8-inch but for me would be more interesting in a small scope.

I’ll come back to these over and over again. My goal, always, is to make objects into familiar old friends.  I don’t keep lists, but I do try to build a relationship with objects that look fresh to me each time I see them in part because I use different telescopes, but also because different nights bring different conditions and, of course, I’m different each time – but how can you exhaust the awe that’s inherent in every astronomical object?

And in that spirit I checked out the Trapezium, of course – just four stars this night, though I saw the E and maybe the F star a few nights ago with this scope. Both seeing and transparency were a notch below average on this night. Still, I was able to get a hint of the faint nebulosity that completes the  M42 loop and shows so well in images.

I had log sheets for three more Orion doubles to check out, but the clouds were now moving in on Orion.  But this was one more example of how good it can be on a less than perfect night – the kind I used to not bother to observe on!

[size=150][b]
Morning and clear again[/b][/size]

I seldom sleep more than 4 hours at a time – not a choice, just the way things are – and so I was up at 4 and out again at 4:30 and this time there were only 10 percent clouds. No plan. I have hot tea and I like to meditate each morning and if it’s clear, I do so at the telescope.  In this case I  quickly locked onto M3, high overhead, and with a 13mm Nagler enjoyed the view. This isn’t what some would call meditation. Heck, it isn’t what I would call meditation. It’s really quiet contemplation. Has some  meditative components and some observing components. Sometimes my eyes are closed. Sometimes they’re open. Always I’m at peace and when I think my thoughts are directed to the star city in front of me. Yes, it’s cold – I guess about 25 degrees – but I’m in my tiny (6-foot)  observatory which with its dome and slit limits the amount of sky to which I radiate heat.

Oh – I checked on Porrima.  Do you know Porrima? I don’t. Geeeeeesh! Half a century of amateur astronomy and I’m still the last kid on the block to discover these things.  I don’t know how many nights I’ve used Porrima as a starting point for finding my way into the Virgo galaxy cluster. I’ve even read stuff in which the writer refers to it as “beautiful Porrima.” Beautiful? That should have been a clue, but it wasn’t. I should have checked it on Jim Kaler’s web site. Kaler is my star guru. I love his books.  But as I said, I’ve used it as a stepping stone when hunting much bigger game – galaxies. Then just recently I learned why everyone loves Porrima. 😳

As Kaler succinctly puts it: Porrima is “one of the finest double stars in the sky.”

And it certainly sounds like it! Two very close, magnitude 3.5 stars. How close? I found this information on the separation and position angle – which is getting wider – in a post on Cloudy Nights:

From the 6th catalog of orbits:

2008 PA 41.3, Sep 0.924

2009 30.7, 1.168

2010 23.7, 1.389

2011 18.5, 1.591

2012 14.4, 1.777

So it’s somewhere around 1.4 arc seconds now. Yeah! But on this morning it still looked like an egg-shaped blob to me.  Now mind you, the collimation is fairly good on this scope, but I really should take the time to fine tune it.  I don’t think that’s the problem. The seeing is a 2 out of 5 – not good.  But boy this whets my appetite. I do want to split this star. This sentence from Kaler [url]http://stars.astro.illinois.edu/sow/porrima.html[/url]certainly sums up the fascination from a technical perspective: “Thirty-eight light years away, the stars average 43 Astronomical Units from each other, about the distance between the Sun and Pluto, the orbital eccentricity taking them between 81 and 5 AU.” So this spring will be the time to go for it.

But I was in the middle of M3 where a mere two stars close together is child’s play. Here we have half a million stars  jammed in a sphere 33,000 light years away. That’s meditation material!

When I leave M3 it still seems dark enough – though it’s after 5 and the Sun rises in about 90 minutes – to see what I can see in the Virgo cluster.  I’ve been using small refractors a lot lately and I’m interested in seeing what an 8-inch scope does with these familiar galaxies, so I simply plunge right in.The Telrad allows me to quickly climb up the three stars that form an arc starting with Porrima, then take a sharp right and go up a tad . . . look in the eyepiece – I’m using a 24mm Panoptic again – and bingo! Two bright galaxies side by side making a triangle with a fairly bright star – and when I look more closely it’s more like a long, thin diamond, for opposite the star is another, much fainter and smaller galaxy. Looks like the beginning of Markarian’s Chain. I sketch it quickly, then look around a bit. Find another galaxy . . . but already the sky is getting light and when I finish up at 5:45 am it is way too bright for galaxy hunting and my hands are getting cold. I think those first two galaxies are M84 and M86,  but I’m not positive until i check my sketching against an online photo. There’s a helpful one here:[url]http://observing.skyhound.com/archives/apr/M_86_01.gif[/url]

The morning’s observing has left me with a dilemma, though. I really like having the LX50 in the observatory. I like using the equatorial wedge, I  like the slow motion controls. And I like the RA motor. (I don’t like the auto focus – removed it – but that’s not the issue here.) The issue is space. My dome is just 6-feet in diameter. I have a pier in the center. Put the LX50 with wedge on that pier and it’s fairly high. Too high most of the time for my office chair I like to use, but OK for an observing chair. However, if I’m high on that observing chair I have to get off it in order to take notes on the counter top which is under a very, very low ceiling/roof. (Think of my observatory as a doghouse with the top lopped off and a dome plopped over part of it and you’ll get the idea. It’s very functional for one person. OK for two – very crowded with three. I envy Pete’s set up where he can seat about 11 people around the scope. When I have even a few folks out to observe I use the deck, not the observatory.

But I bumped my head enough times in this observing session – and bumped the scope enough times – to think that maybe the LX50 has to find a home on the deck, or in the yard. What really works for me in this small building is a T-Mount from Universal Astronomics. That will take a small refractor, or an 8-inch SCT and because of all the ways it can move, allow me plenty of space to operate and to do so without ever leaving my comfortable office chair.  That breathing space, I think, outweighs the advantages of electronic tracking and slow-motion knobs on the LX50.

And if you’re thinking “why not an LX90” or other go to scope, it’s a good question. I built the observatory with my LX200 in mind – that was around 1991 when  the LX200 was so new  the manual I got from Meade was out of a copier – they hadn’t printed the real manuals yet! But that scope is long gone,and so is the LX90 – in fact, so is anything with a computer on it. I know folks love “go to” and I have no beef with them at all – but I don’t. Purely personal preference that depends in part on why you;re observing at all. i really like star hopping and a couple years ago sold all my electronic equipment – go to scopes and a very nice deep-sky video set up – and went back to visual observing and pushing scopes around. Now I’m backtracking just a bit with  the recent purchase of an LX10 and and LX50 on equatorial wedges.  I want to use them a while. See if I like them.  It fun to try to think rational thoughts and make plans, but in the end the only thing that matters to me is took at my own behavior. From a rational standpoint one scope may make more sense than another – but I ask myself a simple question: What do I use? So I’ll drop these wedge-mounted Meades into the mix and if they get used, they stay. If they don’t, they’ll be sold to someone who will use them.

But for the moment, I’m putting the T-mount back in the observatory. It’s more flexible, more comfortable to use, and suits me fine. I do well over half my observing in the open where the LX scopes will get plenty of opportunity to strut their stuff – and I’m anxious to see how those in the little “star hopper” program I’ve started like them.

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