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My 80mm Mizar Shows Me a New Way to Look at Xi (ξ) Boötis

Click on this or any of the other photos for larger views.

Several years ago I was skimming along through Cloudy Nights’ Classic Refractor Forum and I came across a discussion about an old 80mm Mizar refractor someone had purchased that turned out to have a badly chipped lens.  I followed the discussion for a few nights and read with more than a little interest of the owner solving the problem by replacing the old lens with a Carton 80mm f/15 lens.  I forgot about it after a few days, but then one evening I found myself looking at an ad for that very same telescope, with a mouth-watering photograph of it sitting on top a very tall and solid-looking wooden tripod.  Resistance never entered my mind.  My fingers flew across the computer keyboard in response to the ad, and about a week later it arrived at my door.

The long monster showed up well packed in a solid and very heavy wooden box that I opened with devilish delight.   I worked  methodically at removing all the paraphernalia from its slightly musty temporary home, laid each part out carefully, and then whistled and hummed as I pieced it together.  Everything was there, it all worked, the tripod was every bit as stable as it looked in the photo, but the old Mizar EQ head was a rather disappointing piece of –- well -– let’s call it hardware, although even that is more complimentary than it deserved.  I passed that part on to someone at a bargain price, and proceeded to place an old Polaris mount on top of those long brown wooden tripod legs, which couldn’t have been happier.

There was one other problem I had to wrestle with –- I spied it when I bought the scope –- and that was the absence of a dew shield.

Now I live on the north Oregon coast, a part of the world that is both famous and infamous for the amount of rain it gets.  Most years see ninety to one hundred inches of rain, at least sixty percent of which falls from the sky between November and February.  But even when the rain isn’t raining, the moisture content in the air at night makes the use of a dew shield and a dew heater mandatory -– without those two items, the lens of a telescope won’t survive ten minutes before succumbing to the moisture laden atmosphere.

So I had to come up with a dew shield.  That unshielded lens looked great at the end of the scope’s cream-colored tube, but telescopic life would be impossible without it.

One day I happened to be at the local hardware/lumber store and I heard a bell ring in my head as I walked past a piece of PVC tubing.   I ran back home, measured the outer diameter of the exposed lens cell, went back to the store, and found the PVC tubing was the wrong size.  I was about to give up on the idea when I stumbled across a piece of long black plastic irrigation pipe, the same stuff used for mundane things such as sewer lines.  I yanked my tape measure out of my pocket, stretched it across the opening of the pipe ——- and it was within 1/8” of what I needed.

I had ‘em cut a piece down to size, and that’s what decorates the end of that cream-colored Mizar tube.  For some reason that pipe has a real tendency to sweat, both inside and outside, so I added some flocking to the inside of the tube, which cured the inner part of the problem.  I also replaced the focuser with a Crawford Machine Crayford single-speed model, found an old Royal Optics olive green finder that was without a home, attached it to the right side of the tube –- and made the whole thing into a demon of a double star scope.

Now due to a more infamous than normal stretch of that infamous Oregon coastal weather, this poor scope hadn’t seen starlight since last November — which was about six months into the historic rainy past.  Every time I walked past it, I could feel a restless energy radiating from it –- as in “Get me under the stars!  I’m tired of being cooped up in this house!”

So I grabbed it off its storage rack a few nights ago, put it back on top of the old Polaris mount, and marched the whole thing outside.  For some reason the altitude adjustment on the mount had slipped –- it had probably sagged in disappointed expectation of ever seeing starlight again –- so I spent some time re-adjusting and lining everything up.   And when I got done, I had an absolutely delicious, mouth-watering view of Polaris.  I believe I had a 15mm TV Plössl (80x) in the scope, and it displayed the diminutive secondary with something resembling an etched crystal clear clarity.   And the Polarian primary beamed back at me from the center of a yellow-gold diffraction ring which floated and fluctuated in a slow dance around it.  Ah, yes -– another one of  those  moments!   I lingered –- what else could I do?

An 86% full waning moon was beaming lurid rays of yellow-white light onto my right shoulder and into the corner of my right eye, so I decided to swing the scope over to the star it was named for, Mizar, and let the moon bounce its beams off the back of my head.   And again, the view was stunning.  I replaced the 15mm TV Plössl with a 24mm Brandon (50x), which had the effect of pulling Mizar’s two companions closer together.  Beautiful, beautiful, beautiful  ……………… beautiful.  Alcor sat to one side — I could swear it was admiring the view, too –- and right in the middle was Greg’s side car, also known as Sidus Ludoviciana, or Ludwig’s Star.

Then I slid sideways to Alkaid at the end of the Dipper’s handle and aimed a few degrees above it to the northeast to catch a pair of Boötean beauties, Kappa (κ) and Iota (ι) Boötis.   Both pairs of doubles decorated the field at the same time in the Brandon, but I had to look carefully to pick out Iota’s 7.4 magnitude companion (the fainter of the two secondaries), since the moon was doing its best now to turn the sky to daylight.  It was getting more than a little help from a damp haze in the air which was hard at work employing every available molecule of moisture to magnify the moon’s reflected photons.

Next I panned over to Izar and spent thirty minutes or so prying the secondary off of the primary, which I finally managed reasonably well with the 15mm Plössl, and then I looked up and saw a weak glimmer of light coming from about where Xi (ξ) Boötis was supposedly shining.   So I pointed the Mizar’s long white tube in that direction, peered into one of the finders, centered it, and then pulled up my chair and sat down for a long look.

Xi (ξ) Boötis  (Σ1888)                HIP: 72659    SAO: 101250
RA: 14h 51.4m    Dec: +19° 06′
*****  Magnitudes      Separation       PA           Latest Data
AB:      4.8,   7.0                  5.9″            306°        WDS 2012
AC:      4.8, 12.6                71.6″           340°        WDS 2008
AD:      4.8,   9.6              161.1″           286°        WDS 2008
AE:      4.8,   8.7              268.6″           100°        WDS 2009
AF:      4.8,   9.2              333.8″              41°        WDS 2009
Distance: 22.1 Light Years
Spectral Classification:  G8 (A), K5 (B)

The “D” companion can be see just to the west of the AB pair, and the two northernmost of the north-south aligned trio on the opposite side are the “F” and “E” components.  “C” was hiding behind a veil of bright moonlight.  (East & west reversed, click for a larger view).

I was still using the 24mm Brandon, and in its minimal 50x, “B” was barely separated from “A” –- which made the view all that more attractive.  The seeing was slipping slowly from a III to a II, so occasionally the secondary would get yanked back into the primary, and then it would suddenly pop loose again, where it would stay for several seconds.  My eyes roamed across the entire field, caught especially by the trio of stars in a north-south alignment just to the east of the dancing primary/secondary pair –- but they kept coming back to that dance, again and again.

After several minutes of that, I became more aware of the motion in the eyepiece.  There’s no drive on the mount, so the entire field was drifting to the west, which was to the left side of the field of view as I was situated  ——  and it impressed me as a waltz in slow motion.   And then my mind suddenly re-configured the stars in the field into the shape of a goose or a swan.  The primary/secondary pairing was the head, the three stars to their east in the north-south alignment were the wings, and further east  at a distance of about twenty-five arc minutes, were a detached pair of stars that served as the tail.

It was fascinating to sit there and watch that slow motion flight take place.   The entire field of view in that eyepiece amounts to something like a full degree –- that, coupled with the low 50x magnification, was more than enough to result in a very slow trip from the east edge of the field to the west.  I didn’t time it, but I would guess it took close to a minute for the entire configuration to wing its way across the field.

It was another one of  those  moments.

It’s uncanny how they unexpectedly dawn on you.   Suddenly  the view in the eyepiece –- regardless of whether it’s boringly normal or particularly captivating –- takes on a new dimension.   Something that was there all along, but beyond the boundary of conscious awareness, quickly blossoms into view –- and nothing about that field of view strikes you as “boring” or “normal” again.

And that’s what happened.

And when that happens, I’ve learned you don’t leave it quickly.  Your role in the continuing drama of the unfolding of the universe is to sit there at that particular moment in time and soak it all up.   And I did.   For something like thirty minutes.  I didn’t budge, I didn’t move, I barely breathed.   Just me, a 24mm Brandon, an old Polaris mount, a slow motion control, and that long, creamy white Mizar telescopic tube, pointing through the moonlight at a narrow swath of interstellar space twenty-two light years away.

P U R E   bliss!


6 Responses

  1. Howdy Admiral,

    Wonderful stuff! Isn’t it great to resurrect an old scope, however humble, place it atop an elegant mount and repatriate it by pointing it skyward!

    I thinked you finally nailed why it is I have (personally) chosen to observe with alt-az mounts. I’d be the first to acknowledge that a motor-driven equatorial is a useful thing for many observers to have. But those long focal length telescopes give crisp views from edge to edge, making them especailly useful for watching the (true) dyanmic nature of our relationship with the ‘fixed stars’. In a way, it’s more ‘real’ than having it centred in the eyepiece field, moving at the siderial rate. Even basic eyepieces like plossl and orthos have a large enough true field to make the activity worthwhile, even at the higher powers.

    That was another reason I have recently been checking out one of those super duper 100 degree eyepieces. In a recent trip to California, I finally got a chance to check out the Ethos and Explore Scientific beasts. Though the Ethos seemed a shade better, the ES 100 was still very impressive, especially in the 4″ f/9 ish frac I was using. I thought the view might be uncomfortable, having to move your eyeball round the field etc, but it was surprisingly easy on the eye and boy was it immersive! I got a power of near 100x and a near on 1.0 degree field. I know, they weigh a tonne and cost a heap, but I could see one of these being useful for prolonging the kind of experiences you described with Xi Bootis.

    Xi is real close alright, a communion of orange and yellow suns just 22 light years away. And with an A/B orbit of only one and a half centuries or so, these stars are bound to change their aspect fast enough for me to hope to see them quite differently again only a few decades from now! The last time I checked them out, they sure looked waltzin good to my eye. I’ll be sure to check ’em out again once dark (and clear) skies return in the autumn. Jeez…. I never thought I’d hear myself wishing my summer way!

    And as for your good self; you’ll certainly have to take that 80mm Mizar for another spin…..real soon (grin).

    Best wishes,


  2. Couldn’t agree more on the non-driven versus the driven mounts, Neil. There’s certainly a place for the driven mounts — for example, it’s a heck of a lot easier to sketch a star field, especially at at high magnifications. And there’s no doubt I can be spoiled quickly by using one too much. Sometimes I find myself having to resist the G8 at the beginning of a session and force myself to use an alt-az or manual EQ mount.

    But, on the other hand, you couldn’t be more correct about even the eyepieces such as Plössls and Orthos, or others with narrow-field reputations, as being perfectly acceptable for use on non-driven mounts.

    And the main thing of course is the connection with the motion of the earth, something I still have to forcibly remind myself of each and every time I see it — it ain’t the stars that are moving, it’s the ground that’s part of the earth on top of which I’m perched!

    And — there’s a rhythm, too, that establishes itself at each magnification. I find myself reaching up at regular intervals to turn the slow motion knob and return the object of my attention to the east edge of the view so it can start its passage through the eyepiece again. In an odd way, that rhythmic readjustment of position adds an intangible quality to the experience that I miss when I’m using a driven mount.

    But whatever works to make a person’s observing experience rewarding is the main thing. 😉

    Meanwhile, I’ll see if I can pull together some dark skies and send them in your direction!


  3. I got a good split on Xi Boo tonight. I made a sketch at 261X with my 2″ Expl. Sci. 9mm EP. I’ll come back to it on another better night to see if I can nail the other companions. I spied only the AB pair. The humidity is 50% and the moon is first quarter. I did see WDS 14516+1900, TYC 1481-0609, mags 10/12, Sep. 32″ off to the south near the edge of my F.O.V. But I’m stymied why I didn’t get C,D,E,& F. as the mags are less the that pair. The seeing is not so great but I’m waiting up to see the Persieds after the moons sets.

  4. Hi Steve,

    You should have been able to catch all of the components if you were using the 9.25″ SCT. Even with your smaller refractor, they should have been visible with the possible exception of the 12.6 magnitude C component. The moon was actually fairly close to southern Bootes last night, though, so it could be the haze from the humidity and the moonlight blotted everything out except the AB pair. It’ll be moving away from Bootes over the next few nights, but since it will get brighter every night, that won’t do much good. There’s a reason that thing is called the Evil Orb!


  5. You’re right, John. Even at 10,000 ft. conditions can deteriorate. I’ll try again on another night when the moon is dark and the humidity is low… After observing it for a while the airy dist of the AB pair became a fuzz and I lost separation. I packed it in. Waited for the moon to set and watch the meteor shower. That was a dribble so I turned in. I’ve had better nights…

    I completed the AstroLeague Sketching Program last week with 100 objects observed. I’m the tenth completion in the program. Very happy about that. It took about a year to get ‘er done.

    S. McG.

  6. Spent some time last night waiting for the Perseid’s to show up, but I didn’t see much either. I saw several meteors moving TOWARD Perseus, but very few that could be said to radiate outwards from it. Must have been on the wrong side of the world again!


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