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The Double Stars of Collinder 65, Part Two: OΣ 107, OΣ 108, HJ 3274, and HJ 3275

Now on to the last group of double stars in CR 65, which are located in the north part of the cluster.  If you missed part one, you can get to it by clicking on this link.

Here are our charts once again, starting first with a wide view:

Stellarium screen image with labels added, click for a larger view.

Stellarium screen image with labels added, click for a larger view.

And here are the finder views with the distances shown, starting with an erect image view:

This is an erect image chart, which will match the orientation you see in an RACI (right angle,correct image) 8x50 finder. (Stellarium screen image, labels added, click to enlarge).

This is an erect image chart, which will match the orientation you see in an RACI (right angle,correct image) 8×50 finder. (Stellarium screen image, labels added, click to enlarge).

And here’s the mirror-reversed image for use at the eyepiece of a refractor or SCT:

Stellarium screen image, labels added, click to enlarge:

Stellarium screen image, labels added, click to enlarge:

We’ll begin with an Otto Wilhlem von Struve discovery, OΣ 107. If you start at S 478, aka 111 Tauri, which is located near the middle of the west edge of CR 65, you’ll find OΣ 107 located 52’ to the northeast. If you have any influence with the sky guys and/or gals who control the seeing, give ‘em a call on the celestial night line – it’ll make things easier!

OΣ 107 (STT 107)         HIP: 25499    SAO: 94554
RA: 05h 27.2m    Dec: +17° 58’

Identifier  Magnitudes Separation  PA WDS
MCA 19 Aa, Ab:   5.80,  6.80      0.10″    89°  2007
STT 107 AB:   5.39, 10.10     10.30″  306°  1998
STT 107 AC:   5.39, 11.80     10.10″  346°  1998
STT 107 BC: 10.10, 11.80      7.00″    59°  2012

Distance: 549 Light Years (Simbad)
Spectral Classifications: “A” is B5, “B” is F8

On first glance, this scene reminded me of the alignment of Σ 697, which was the last star we looked at in part one. Alluring as the scene is, though, the two stars lined up to the west of the primary are not cataloged as part of OΣ 107.

In fact, you’ll have to look at the inset to see the “B” and “C” companions of the primary.   (East & west are reversed here to match the refractor image, click on the sketch for a better view of the close companions).

In fact, you’ll have to look at the inset to see the “B” and “C” companions of the primary.  Also shown here to the northwest of the primary is TDS 3195 with magnitudes of 10.6 and 10.98, separated by 0.4″ at 62 degrees (WDS 1991) — a bit beyond my reach!   (East & west are reversed here to match the refractor image, click on the sketch for a better view of the close companions).

I had a devil of a time prying both “B” and “C” out of the glare of the primary using the five inch refractor, but persistence finally paid off.  Not surprisingly, “B” popped into view first, and once I had it, patience added to more persistence finally resulted in “C” making an appearance.  The seeing was about average, although it was wavering between II and III on this chart.  The trick was to sit and wait for moments of good seeing and then to be quick with the eye.  It took several glimpses before I was convinced I was looking at “C”, and I went back later with a six inch refractor to confirm I had it.

Click to enlarge.

Click to enlarge.

There hasn’t been much change over the years in the measures of the AB and AC pairs, as can be seen in the excerpt at the right from William Hussey’s book on Otto Struve’s double star discoveries.  The position angle for AB measured in 1842 by Mädler (Ma) is at odds with the other measures, but otherwise, the PA’s average out to about 307°.

As for AC, it’s obvious from Hussey’s narrative the “C” component is difficult to measure (Otto Struve estimated the position angle), which probably is due to the glare caused by the primary. Hussey also found “C” was difficult because of its faintness, even with the twelve inch refractor at Lick Observatory. The most recent position angle in the WDS, 346°, seems to be at odds with the data in Hussey’s list, which probably is a further indication of the difficulty in measuring it.

I checked several photos of STT 107 in hopes I could get a measurement for both AB and AC, but the primary is so bright it blots out the “B” and “C” components.   There’s very little proper motion in the primary, +008 -021 (.008”/yr east, .021”/yr south), which corresponds with the minor change in the AB pair, but there’s no proper motion data on either “B” or “C”.

Now we’ll move on to OΣ 107’s sibling, OΣ 108, which is a short 39′ jaunt northeast from our current location.   Once you have it in view, you’ll find it’s accompanied by HJ 3275 to its northeast. (Here’s the erect image chart again, and the mirror-image chart).

OΣ 108 (STT 108)         HIP: 25702    SAO: 94586
RA: 05h 29.3m   Dec: +18° 22’
Magnitudes: 6.77, 10.42
Separation:  3.2”
Position Angle: 130° (WDS 1994)
Distance: 609 Light Years (Simbad)
Spectral Classification: “A” is A2

This is another tight pair which is made more difficult by a large magnitude difference, in this case a spread of 3.65 magnitudes.   I used the same procedure described above in order to catch a glimpse of the secondary with the five inch Meade, and made a second visit with a six inch refractor in order to confirm it.

This hand-full of scattered starlight includes all three of our remaining stars.   The secondary of OΣ 108 is visible in the upper inset on the right. The inset below, which is included for identification purposes, represents the same magnification as the larger sketch.   (East & west reversed once more, click on the sketch for a much better view).

This hand-full of scattered starlight includes all three of our remaining stars. The secondary of OΣ 108 is visible in the upper inset on the right. The inset below, which is included for identification purposes, represents the same magnification as the larger sketch. (East & west reversed once more, click on the sketch for a much better view).

Click to enlarge.

Click to enlarge.

Hussey’s 1898 observations of OΣ 108 are shown at the right, along with Otto Struve’s 1849 observation and four additional observations Hussey took from Burnham’s 1906 catalog.   Apart from Otto Struve’s 1849 position angles of 137.1° and 139.5°, the measures shown are pretty consistent.  Comparing that data with the 1994 position angle and separation in the WDS, it looks like this pair has moved slightly closer.  At the bottom of that page, I also included three later observations which come from R.G. Aitken’s 1932 New General Catalogue of Double Stars Within 120° of the North Pole, which continue the consistency in position angle and separation.

There isn’t much proper motion in the case of either star, but what stands out in the WDS data is the two stars are moving parallel to each other, with the primary moving at a rate of -015 -005 (.015”/yr west, .005”/yr south) and the secondary at a rate of -013 -004 (.013”/yr west, .004”/yr south).  That would indicate the measurable change in PA and separation should be negligible, or at least less than what the 1994 WDS measures indicate.  It’s possible the close proximity of the two stars, along with the wide magnitude difference, also makes this a tough pair to measure.  At any rate, since the last WDS date of measure is 1994, it looks like this pair could use an update.

Also included on the sketch above are two John Herschel discoveries, one of which was supplemented with additions by S.W. Burnham and Robert G. Aitken.

HJ 3275        HIP: 25745   SAO: 94589
RA: 05h 29.8m   Dec: +18° 25’

Identifier Magnitudes Separation  PA WDS
Bu 891 AB:  7.65, 13.60     10.60″ 128°  2000
HJ 3275 AC:  7.65,  8.22     56.30″   21°  2011
A 2433 CD:  8.22, 11.98      1.40″ 254°  1999

Distance: 567 Light Years (Simbad)
Spectral Classifications: “A” is A0, “C” is F

HJ 3274      No HIP or SAO Number
05h 29.7m   Dec: +18° 19’
Magnitudes: 11.04, 11.23
Separation:   5.3”
Position Angle: 107° (WDS 2000)
No distance or spectral classification in Simbad or WDS

Click to enlarge!

Click to enlarge!

John Herschel’s observations of HJ 3274 and HJ 3275 are shown at the left, but if you look at his data, you’ll see what appear to be estimates for HJ 3274 and no data at all, apart from magnitudes, on HJ 3275, which he describes as a “coarse double star” (probably a reference to their separation).   Also included on that page are his observations of Σ 697 and Σ 730, which were covered in part one of these posts on CR 65 (source).

HJ 3274 is the less impressive of the pair, and it takes an observant eye to catch the two faint stars. I wasn’t aware it of it when I first looked at this field, but as I was studying HJ 3275 I caught a hint of its duplicity out of the corner of my eye. When I gave it more attention, I was able to pry the secondary loose without too much effort.

HJ 3275 is the more interesting of the two, mainly because it’s been expanded from the two obvious components to include two more members, both of which are difficult to catch.

Click to enlarge.

Click to enlarge.

R.G. Aitken first caught sight of the tough CD pair in 1912, which was well beyond my seeing-limited reach on the two nights I looked for it.   I found that observation in his 1932 New General Catalogue, which includes measures for the AB pair (β 891) as well as the AC pair (h 3275), also referred to by Aitken as number 64 in Otto Struve’s appendix catalog. He expands the historical record even further when he refers to A 2433 as having been cataloged as JC 883. The JC refers to W.S. Jacob, whose observation I was unable to locate, although I did find several of his star catalogs. (Here’s more information on Jacob, who was an interesting observer in his own right).

S.W. Burnham was the first person to excavate the 13.60 magnitude “B” component from the 7.65 magnitude glare of the primary, using the 18 ½ inch refractor at Dearborn Observatory in 1879 (that observation is shown above in Aitken’s catalog).

Click to enlarge.

Click to enlarge.

If you compare Burnham and Aitken’s data, you’ll see the position angle of the AB pair meanders from 121.6° (1879) to 126.7° (1891) to 122.2° (1898) to 126.2° (1910) to 128.5° (1917), while the separation remains in the 10.6” range except for Burnham’s 1879 measure. More than likely the glare of the primary also makes this pair difficult to measure.

Burnham’s perceptive eye also detected an increase in separation taking place between “A” and “C”, which is confirmed by looking at the WDS proper motion numbers. This Aladin photo, with the aid of an overlay from Simbad, shows why the distance between the two stars is slowly increasing:

This is an erect image, so east and west are opposite of my sketch above.   Click for a better view.

This is an erect image, so east and west are opposite of my sketch above. Click for a better view.

There’s no proper motion data for the “B” component, but based on the 2000 WDS separation for AB at 10.60”, which is essentially the same as Burnham and Aitken’s data, it appears the two stars may be moving in tandem with each other.
_____________________________

There’s one other aspect of the Collinder 65 cluster worth looking at, which is the relation of the various stars to each other.  Normally an open cluster is a group of stars with similar distances, most of which are moving in the same direction.  For example, here’s a listing of the brighter stars in the Hyades cluster (the distances in black are members of the cluster), which is located fourteen degrees west of CR 65.  (That chart is included at end of this rollickingly informative post).

Compare that chart with this one showing the major luminaries of CR 65 . . . . . . .

Star    Dist (LY)      PM RV (km/s)
S 478          47
110 Tau        407
STT 107        549 +008 -021   +14.9
113 Tau        565 +001 -006   +27.2
HJ 3275        567 +003 -039     +1.0
STT 108        609  -015 -005
117 Tau        613 +017 -045
116 Tau        685
STF 697        874
STF 730      2991
 ———  ———-
122 Tau        158
120 Tau      1552
119 Tau      1791

. . . . . . . and you find the stellar distances are nowhere near as similar as those of the Hyades.   I highlighted three stars in red with similar distances, and another pair in green.   The three in red do in fact have similar proper motions, indicating a possible physical relation.  However, in order to get a three-dimensional view of what’s taking place, I included their radial velocities (RV), which tells us how fast the stars are moving towards us or away from us (in this case, away from us).   Adding that third dimension leads to the opposite conclusion.  As for the two stars in green, the proper motions are all we need to determine they’re unrelated.

I also expanded the boundary of CR 65 a bit to take in the last three stars at the bottom of the list, just to see if any of them might have distances similar to a few of those within the boundaries of the cluster – and it’s obvious they don’t.

So whatever criteria Collinder used for grouping this scattering of stars into a cluster, it apparently had nothing to do with their being physically related.  One more stellar mystery for the books!

Next tour will take us north of the Hyades to a small (non-clustered) group of four stars, two of which deserve to be better known than they presently are.

Clear Skies!  😎

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The Double Stars of Collinder 65, Part One: Σ 730, S 478, and Σ 697

Located north of the head of Orion and south of the horns of Taurus is a large open cluster known as Collinder 65 (CR 65), which is unlabeled on some star charts. You’ll find it about five degrees north of Lambda (λ) Orionis, stretched out across the Orion-Taurus border. (Lambda (λ) Orionis, a beautiful multiple star better known as Meissa, is at the center of another Collinder open cluster, CR 69).

Stellarium screen image with labels added, click to enlarge.

Stellarium screen image with labels added, click to enlarge.

The diameter of CR 65 varies, ranging from 140’ (2.3°) to 220’ (3.7°), depending on which source you consult. At any rate, it’s noticeably larger than its Orion relative, CR 69.

Stellarium screen image with labels added, click for a larger view.

Stellarium screen image with labels added, click for a larger view.

Both clusters are enticing binocular objects and rival one another in aesthetic appeal. Whereas CR 69 is dominated by the beautiful cream-colored white light of Meissa, CR 65 is illuminated by a handful of fifth and sixth magnitude Flamsteed-numbered stars. Scattered within that steady starlight are half a dozen multiple stars beckoning to the yearning eyes of a double star connoisseur.

The six double stars we’re going to look at are identified here in tantalizing turquoise. (Stellarium screen image with additional labels, click to enlarge).

The six double stars we’re going to look at are identified here in tantalizing turquoise. (Stellarium screen image with additional labels, click to enlarge).

The image above is a close approximation of what you would see in an 8×50 finder. In order to find your way around and have a sense of scale, it helps to know the distances between the various points, as well as the direction from star to star.   Those morsels of information were invaluable later when I navigated from one star to the next while looking through an eyepiece.  Below is the same image as above, but with the distances and directions added:

This is an erect image chart, which will match the orientation you see in an RACI (right angle,correct image) 8x50 finder. (Stellarium screen image, labels added, click to enlarge).

This is an erect image chart, which will match the orientation you see in an RACI (right angle,correct image) 8×50 finder. (Stellarium screen image, labels added, click to enlarge).

For use at the eyepiece of a refractor or SCT, here’s a mirror-reversed image of the same scene:

Stellarium screen image, labels added, click to enlarge:

Stellarium screen image, labels added, click to enlarge:

We’ll start with Σ 730, which is located at the center of the eastern edge of CR 65.

Σ 730       HIP: 25950    SAO: 94630
(AB is also H III 93, H N 124, and Sh 58; Aa, Ab is OCC 999)
RA: 05h 32.2m   Dec: +17° 03’
Magnitudes  Aa, Ab: 7.30, 7.30   AB: 6.06, 6.44
Separations  Aa, Ab: 0.10”          AB: 9.60”
Position Angles  Aa, Ab: ?????   AB: 141° (WDS 2013)
Distance: 2991 Light Years (Simbad)
Spectral Classifications: “A” and “B are both B7

There was no doubt about the color of the AB pair – pure white.   Not included among the components of Σ 730 is the eleventh magnitude star located about 1.5’ southeast of AB at about 155 degrees. (East & west are reversed here to match the refractor view, clicking on the sketch will enlarge it).

There was no doubt about the color of the AB pair – pure white. Not included among the components of Σ 730 is the eleventh magnitude star located about 1.5’ southeast of AB at about 155 degrees. (East & west are reversed here to match the refractor view, clicking on the sketch will enlarge it).

This is a pair of stars that received attention from all the well-known double stars observers of the late 18th and early 19th centuries: William Herschel, John Herschel, James South, and F.G.W. Struve.  It began with William Herschel seemingly confusing this pair of stars with 117 Tauri (source, scroll down to sixth title):

Wm Herschel on STF 730 as H 3 93

His position angle (which translates to 142° 27’) and separation for the two stars are reasonably close . However, his identification of this pair as 117 Tauri is an error which was discovered in 1821 by John Herschel and James South when they went in search of 117 Tauri and found it was a single star. Their discussion below is very clear and easy to follow (source, scroll down to last title):

Click to enlarge.

Click to enlarge.

If you read the quotes from Herschel’s observing notes carefully, which are just past the mid-point of the page, it’s clear that William Herschel was using 117 Tauri as a reference point to reach the star now identified as Σ 730.  Herschel frequently included a Flamsteed-numbered star as a reference point in the first line of his observations, but in this case he left out the distance between 117 Tauri and the double star he observed in the published version, which led to John Herschel’s and James South’s search for it.  Fortunately, they had access to William Herschel’s notes.

Prior to the John Herschel-James South observation, William Herschel apparently observed this pair of stars a second time in 1800 and cataloged it again as H N 124 (source):

Herschel on STF 730 as HN 124

That observation is rather difficult to follow.   Apart from the coordinates, which match reasonably closely with those of Σ 730, his magnitudes of 9.9 don’t match at all, and I haven’t yet figured out what the Orion reference in the second line refers to.  I’m not all that convinced the pair of stars he described in 1800 is the same pair he saw in 1782. Nevertheless, H N 124 is treated as a duplicate of H III 93 by S.W. Burnham in his 1906 catalog, and the WDS refers to H N 124 in its notes on Σ 730.

Next, we’ll traverse the middle of CR 65 in search of S 478, which is on the west side of this cluster at a distance of 1° 52’. You can see by the 280° position angle I included on the last chart (here’s the erect image, and the mirror image) that we’re going to move almost due west with a very slight inclination toward the north.  Using 5.77 magnitude 117 Tauri as a stepping stone should get you to S 478 with little problem.

S 478      HIP: 25278    SAO: 94526
(AB is also H V 110; AC is WNO 52)
RA: 05h 24.4m   Dec: +17° 23’
Magnitudes   AB: 5.06, 8.79    AC: 5.06, 7.88
Separations  AB: 106.70”        AC: 705.20”
Position Angles   AB: 271°  (WDS 2011)   AC: 252° (WDS 2010)
Distance: “A” is 46.9 Light Years, “C” is 45.9 LY  (Simbad)
Spectral Classifications:  “A” is F8, “B” is K0, “C” is K4

The S 478 trio is a captivating visual delight. The white primary dominates the view, but the very slight hints of reddish-orange in the ninth magnitude “B” component and the wide eighth magnitude “C” component adds a touch of magic to the scene, and the 7.6 magnitude white light of SAO 94531 adds an extra touch of luster. (East & west reversed once more, click on the sketch to improve the view).

The S 478 trio is a captivating visual delight. The white primary dominates the view, but the very slight hints of reddish-orange in the ninth magnitude “B” component and the wide eighth magnitude “C” component adds a touch of magic to the scene, and the 7.6 magnitude white light of SAO 94531 adds an extra touch of luster. (East & west reversed once more, click on the sketch to improve the view).

The AB pair was measured by Sir William Herschel during his observation of November 13th, 1782 (source, scroll down to sixth title):

Wm Herschel on S 478

His Flamsteed number, 111 Tauri, is correct in this case, but the separation he recorded is off considerably, which was noticed by James South when he observed the AB pair on January 17th and February 2nd, 1825 (source):

South on S 478

On the last line of his observation, South refers to the minor change in position angle of the primary and secondary as being too small to account for the large difference in his and Herschel’s separation measures. Those position angles translate to 273° 48’ for Herschel and 271° 17’ for South, and they’re the first hint of significant motion taking place in one of the two stars.

As it turns out, the primary has a rather high rate of proper motion, which is partly attributable to its relatively close distance of 46.9 light years from us.  The “C” component, cataloged in 1897 as WNO 52, has a very similar rate of proper motion, and is located at a comparable distance, 45.9 light years.  The Aladin photo below shows the rates of proper motion of all three of the S 478 components:

Note that this in an erect image view, so east and west are opposite of what is shown in the sketch above of S 478. Click for a larger view.

Note that this in an erect image view, so east and west are opposite of what is shown in the sketch above of S 478. Click for a larger view.

Click to enlarge.

Click to enlarge.

The similar motions of “A” and “C” are obvious, which in combination with their almost identical distances from us, has led to the conclusion the probability of their being physically related is close to 100%. The AB pair, on the other hand, is an optical pair, which is evident from the different rates of motion and direction of “A” and “B”.

The “C” component was added to S 478 in 1897 by the Washington Naval Observatory, which is the source of the WNO identifier assigned to AC. Also, there’s an eleventh magnitude star (TYC 1300-355-1) located 32” from “C” at a PA of 136°, for which there is no proper motion data, so it may or may not be moving in tandem with S 478 “A” and “C”.

You may have also noticed on the image above that S 478 “A” is labeled “BY Dra”, which is a reference to a class of variable star. The AAVSO (American Association of Variable Star Observers) designation for S 478 “A” (or 111 Tauri) is V1119 Tau.  Their data on the star shows a magnitude range of 4.98 to 5.02, so don’t hold your breath in anticipation of a wild swing in brightness.   The WDS data (shown above at right) also includes a note that S 478 “A” is a spectroscopic binary, which may account for its slight change in magnitude level.

So as you can see, hidden behind the visual appeal of the three stars of S 478, there are several layers of intriguing detail.

To get to our third stellar destination, Σ 697, we’ll move south and very slightly west a distance of 42.5’ to 6.1 magnitude 110 Tauri, and then continue due south another 39’ to our goal.  (Here’s the erect image again, and the mirror image).

Σ 697       HIP: 25207    SAO: 94512
RA: 05h 23.5m    Dec: +16° 02’

Identifier Magnitudes Separation PA WDS
STF 697 AB: 7.27,   8.10      25.90″ 286°  2015
WAL 38 AC: 7.27, 10.83      97.90″ 284°  2012
SMR 3 AD: 7.27, 10.07    249.30″ 285°  2012
SMR 27 AE:* 7.27, 12.00    163.00″ 290°  2012

Distance: 874 Light Years (Simbad)
Spectral Classifications: “A” is B8, “B” is A, “D” is B9

Note: The magnitude of E has been changed to 13.89; see comment below in red.

When I first looked at the data on Σ 697, I was immediately intrigued by the similar position angles of all five of the components. And even though I was prepared for what I saw, I was still impressed by the sheer unlikely beauty of the configuration.  Even 7.50 magnitude SAO 94498 and 8.53 magnitude HIP 25287 managed to line up with the components of Σ 697:

“A” and “B” caught my eye first, but it didn’t take more than a few seconds before “C” and “D” popped into view. I never did catch sight of twelfth magnitude “E”, which puzzled me since it should have been within reach of my five inch refractor. Both “A” and “B” are white, as are SAO 94498 and HIP 25287. (East & west reversed to match the refractor view, click on the sketch to get a better look at “C” and “D”).

“A” and “B” caught my eye first, but it didn’t take more than a few seconds before “C” and “D” popped into view. I never did catch sight of twelfth magnitude “E”, which puzzled me since it should have been within reach of my five inch refractor. Both “A” and “B” are white, as are SAO 94498 and HIP 25287. (East & west reversed to match the refractor view, click on the sketch to get a better look at “C” and “D”).

I had a suspicion the 10.07 magnitude shown in the WDS for “E” was too bright, so I pulled up an Aladin photo in order to first make sure the star existed. What I found was a reddish-orange star, which partially explained why it was difficult to see. I never was able to come up with a spectral classification for that star, but I did find magnitudes for it in both the UCAC4 and the Nomad-1 catalogs. UCAC4 shows a visual magnitude of 13.885 for “E”, and Nomad-1 lists it at a visual of 13.710, which explains why I couldn’t detect any sign of it in my five inch refractor. That component is a candidate for a magnitude change, so I’ll be in contact with Bill Hartkopf at the WDS.  (NOTE: The magnitude of “E” has been changed to 13.89 as of 2/13/2015 and the UCAC4 proper motion data has also been added).

This is an erect image, so east and west are opposite of my sketch above. Click to enlarge.

Click on the image and the data will be easier to read!

Click to enlarge.

Click to enlarge.

The AB pair, which seems to have eluded William Herschel, was discovered in 1828 by F.G.W. Struve, as shown at the left (source).  As the excerpt shows, there’s been little change in the position angle and separation since 1828, which matches well with Simbad’s proper motion data on the two stars: -001 -008 (.001”/yr west, .008”/yr south) for the primary, and -003 -004 (.003”/yr west, .004”/yr south) for the secondary.  In fact, there’s little movement among all four of the stars for which proper motion numbers exist, but what little motion there is suggests none of them are related physically to one another:

This is an erect image, so east and west are opposite of my sketch above. Click to enlarge.

This is an erect image, so east and west are opposite of my sketch above as well as the photo above. Click to enlarge.

We’ll cover the last three multiple stars of CR 65 in the next post, along with a bonus that wasn’t on my list.  Hopefully we’ll have some good seeing — we’re going to need it for this group!

Clear Skies!  😎

A West Orion Odyssey: WEB 3, ARN 63, HJ 698, Σ 700, and HJ 697

Mysteries abound in the universe, many of them obscure and many of them subtle, and many more mind boggling beyond belief —– and then there are others that leave you shaking your head and wondering how something so obvious could have been missed so completely. To be less obscure and more direct, how do two eye-catching, very distinctive triple stars sitting five and nine arc minutes from an F.G.W Struve discovery, and twice that distance from a much fainter John Herschel discovery, end up being ignored by both of those observers? And to compound the perplexity, once both of these distinctive triple stars achieves recognition, each is cataloged as a double star. What goes on in this deep dark sector of the sky? Only the sky gods know —– and they’re not talking.

At any rate, mystifying as that situation is, it’s also very mesmerizing.  Would you believe four double and/or triples stars all within a single field of view? In fact, the farthest distance between them amounts to a mere seventeen minutes of arc.

And as long as we’re straining credulity to the breaking point, we may as well wander another one and half degrees south of that quadruple collection of multiple stars to another double star with a more – pardon the phrase – companionable mystery.

First, let’s look at the wide view in order to get ourselves oriented:

Our Orion Odyssey begins just a few degrees west of Mintaka, also known as Delta (δ) Orionis, in the area within the turquoise circle.   (Stellarium screen image with labels added, click on the chart to enlarge it).

Our Orion Odyssey begins just a few degrees west of Mintaka, also known as Delta (δ) Orionis, in the area captured within the turquoise circle. (Stellarium screen image with labels added, click on the chart to enlarge it).

And then let’s close in on our targets:

Starting at Mintaka, we’ll move northwest a distance of 40 arc minutes to 6.87 magnitude HIP 25727, then continue northwest for a full degree to 6.16 magnitude HIP 25378, and then make one more northwest leap for a distance of 52 arc minutes to reach 7.6 magnitude Σ 700. (Stellarium screen image with labels added, click to a larger view).

Starting at Mintaka, we’ll move northwest a distance of 40 arc minutes to 6.87 magnitude HIP 25727, then continue northwest for a full degree to 6.16 magnitude HIP 25378, and then make one more northwest leap for a distance of 52 arc minutes to reach 7.6 magnitude Σ 700. (Stellarium screen image with labels added, click to a larger view).

Center Σ 700 in your eyepiece at a moderate magnification, say 50x to 75x, and you’ll find a dazzling field of subdued starlight that includes these four stars:

WEB 3     No HIP number    SAO: 112705        ARN 63     HIP: 25179   SAO: 112707
RA: 05h 23.1m   Dec: +01° 17’                             RA: 05h 23.2m   Dec: +01° 08’
Magnitudes: 7.29, 10.45                                        Magnitudes: 7.97, 10.1
Separation:  62.2”                                                   Separation:  39.5”
Position Angle: 10°  (WDS 2003)                         Position Angle: 65°  (WDS 2003)
Distance: ?????                                                      Distance: 830 Light Years
Spectral Classifications: K2 and F                      Spectral Classifications: B6 and A2

Σ 700  (H I 75)   HIP: 25174   SAO: 112704        HJ 698     No HIP No.    SAO: 112688
RA: 05h 23.1m   Dec: +01° 03                               RA: 05h 22.4m   Dec: +01° 04’
Magnitudes: 7.69, 7.89                                           Magnitudes: 10.24, 13.0
Separation:  4.9”                                                      Separation:  14.2”
Position Angle: 6°  (WDS 2011)                            Position Angle: 243°  (WDS 2000)
Distance: 750 Light Years                                      Distance: ?????
Spectral Classifications: B9, B9.5                        Spectral Classification: F0
Note:  STF 700 is also known as V1804,            Note: Simbad has B at a mag. of 12.4
an Algol type eclipsing variable with a
period of 2.222878 days.

And since you can’t tell the players without a scorecard, here’s a labeled sketch of the area (there’s an unlabeled version at the end of this post, also):

Σ 700 is the dominant multiple star in this field because of its brightness relative to the other multiple stars, but ARN 63 and WEB 3 are pretty distinctive, too, even at 67x.   If any of the four multiple stars was likely to have been missed, it would be the much dimmer and difficult to separate HJ 698. White, by the way, was the only color visible, except for the very slight reddish-orange tint of WEB 3’s 7.29 magnitude primary.   (East & west reversed to match the refractor view, click on the sketch for a much better view).

Σ 700 is the dominant multiple star in this field because of its brightness relative to the other multiple stars, but ARN 63 and WEB 3 are pretty distinctive, too, even at 67x. If any of the four multiple stars was likely to have been missed, it would be the much dimmer and difficult to separate HJ 698. White, by the way, was the only color visible, except for the very slight reddish-orange tint of WEB 3’s 7.29 magnitude primary. (East & west reversed to match the refractor view, click on the sketch for a much better view).

I was wrestling with another night of poor seeing and murky skies, so the 100x I used for the inset at the right of the sketch was about as high as I could go and still maintain something resembling a focused image. Even at the 67x used for the main sketch, Σ 700 was a shaky sight, but nevertheless it was clearly elongated at that magnification. HJ 698 was also a struggle, thanks to the 2.76 magnitudes of difference between them – although I should point out Simbad lists the secondary at a magnitude of 12.4 (versus the 13.0 in the WDS), which is enough of a difference to provide some advantage given the observing conditions.

Click on the image to enlarge it.

Click on the image to enlarge it.

On the other hand, ARN 63 and WEB 3 were pure visual simplicity itself. At the low magnification I was using, I found both far more visually appealing than Σ 700 and HJ 698. If I had been looking through a telescope with either F.G.W. Struve or John Herschel in 1827, the year each of them made their measurements of the two stars with their initials attached (the senior Struve’s observation is shown at the right, J. Herschel’s is located further down the page), my eye would have been drawn north to both ARN 63 and WEB 3.  Surprisingly, though, WEB 3 didn’t receive measured attention until sometime in the last half of the 19th century (there’s another mystery here: the Reverend T.W. Webb died in 1885, but the first measure for WEB 3 listed in the WDS is dated 1909). ARN 63, on the other hand, wasn’t measured until 2003.

Apart from the fact that ARN 63 and WEB 3 were ignored by both Struve and Herschel, there are two other puzzling mysteries. One is the fact that both stars impress one as possible triple stars on first sight, and the other has to do with the 1892 date of first measurement listed in the WDS for ARN 63.

First, I should point out that it was common for many of the earlier double star observers to establish a limit for separations between components, meaning anything beyond their self-imposed limit was usually ignored. R.G. Aitken wrote an article in 1910 stating Struve’s limit was 32”, which would explain why he passed on both ARN 63 and WEB 3.   I’ve never come across any mention of what separation limit Sir John Herschel employed, but his catalogs do contain a few stars wider than both ARN 63 and WEB 3, although they’re comparatively rare (examples are HJ 980, which he measured at 70” in 1827; and HJ 1079, which he measured at 60” in 1828).

That leaves the triple aspect of ARN 63 and WEB 3 unexplained.   Again, it could be a case of the third stars exceeding the separation limits employed by the observers who first measured these two stars, although I’ve come across numerous cases of companions exceeding the distances of the third star of each of these pairs. What’s clear, however, is there never was – and still isn’t — any standardized separation limit in use from one observer to the next. Nevertheless, it would seem to make sense to extend measures to these third companions in order to provide an initial base for comparing later measurements in an effort to determine whether an orbital relation exists.

And then that leaves us with that 1892 date of first measurement in the WDS for ARN 63. When I first saw that, I assumed someone discovered and measured the star that year.   But as I looked into it further, I found the ARN of ARN 63 belongs to Dave Arnold, who was credited with being the first to measure the star in 2003. That raised the question of why a star with a first measurement date of 1892 would be assigned an identifying prefix in 2003, so I began a long search through the old star catalogs I’ve collected over the years in hopes of finding the name associated with the 1892 date – and kept running into one dead end after another.

My next step was to send an email to Dave Arnold, who graciously replied that as he measured known double stars and came across pairs he was unable to identify, he submitted them to Brian Mason at the US Naval Observatory (USNO) to determine if they had previously been measured. If not, or in a case where measures existed but no credit had ever been assigned, Brian applied the ARN prefix to the star.  Dave suggested I get in touch with Brian to see what information he had.

I had already been in touch with Brian to get the observational data for ARN 63, which also showed measurements of that pair of stars had been made in 1909, 1910, 1929, 1963, 1982, 1991, and 2000. So I contacted Brian again, asking especially about the first three dates, which I had also researched and drawn blanks on.  And at that point I learned something new and very impressive.

All of the measures for the dates prior to 2003 were determined by matching data from various astrometric catalogs kept at the U.S. Naval Observatory in Washington, D.C., which is the home of the Washington Double Star Catalog (WDS).   In other words, using their collection of catalogs, it was possible to determine position angles and separations all the way back to 1892. I’ve always had an immense amount of respect for the resources provided by the WDS, but that additional insight into the capabilities available to the USNO confirms what a priceless resource it is.

Now, on to HJ 697, which lies a short one and a half degrees south of Σ 700. Going back to our second chart again (click here to open it in a second window), with Σ 700 centered in an 8×50 finder, you should be able to catch sight of 4.74 magnitude 22 Orionis, hugged closely by HJ 697. You can also use 6.16 magnitude HIP 25378 and 5.70 magnitude HIP 25223 as visual stepping stones to navigate to it.

HJ 697           HIP: 25028   SAO: 132024
RA: 05h 21.5m   Dec: -00° 25’
Magnitudes   AB: 5.68, 13.05    AC: 5.68, 11.88
Separations  AB: 33.10”             AC: 42.30”
Position Angles   AB: 66° (WDS 2000)    AC: 118° (WDS 2000)
Distance: 1077 Light Years
Spectral Classification:  “A” is B3, “B” is G1, “C” is G3
Notes: “B” had been classified as optical.

 Both the primary of HJ 697 and 22 Orionis are white, and I found a surplus of glowing photons around both stars at 200x. “B” and “C” are easily seen, and if you look carefully, you’ll see another faint star at the southern edge of the primary.   What the heck is that??? (East & west reversed to match the refractor view, click on the sketch to improve the view).

Both the primary of HJ 697 and 22 Orionis are white, and I found a surplus of glowing photons around both stars at 200x. “B” and “C” are easily seen, and if you click on the sketch to enlarge it and look carefully, you’ll see another faint star at the southern edge of the primary. What the heck is that??? (East & west reversed to match the refractor view).

I found “B” was surprisingly easy to see for a star listed with a magnitude of 13.05.  So I checked the visual magnitude in Simbad, and found it listed there at 11.3, which may actually be brighter than what I saw. It’s hard to be sure, though, since “B” is nine arc seconds closer to the primary than “C”. At any rate, it’s magnitude is certainly brighter than 13.05.

And then there’s that “companionable” mystery star clinging to the primary at a position angle of about 165 to 170 degrees. How did it get there, how did John Herschel miss it, and how did S.W. Burnham miss it???

To start at the beginning, Chris Thuemen sent both Steve Smith and I a photo of HJ 697 a few months ago which hinted at the existence of an unlisted component at the primary’s south edge:

Click to enlarge.

Click to enlarge.

A short while later, Steve was able to get a photograph showing the mystery star very clearly:

I’ve flipped both photos to match the mirror-image refractor view shown in my sketch above.   Click on the image to enlarge it.

To avoid confusion, I’ve flipped both photos to match the mirror-image refractor view shown in my sketch above. Click on the image to enlarge it.

And of course, after seeing Steve’s photo, I wondered if it would be possible to visually detect the mystery star in a six inch refractor.  As my sketch above shows, it was, although it required some intense scrutiny and patience.  But there was no doubt it was visually accessible, which takes us back to my questions a few paragraphs back.

Sir John Herschel’s observation of HJ 697 is shown below (the source can be found here), which shows the “B” and “C” components, but makes no mention of the mystery star.   You might notice his separations for the two components are noticeably different than the current measurements, although his position angles are close (“nf 20” is equal to 70° and “sf 30” equals 120°). More than likely his numbers are estimates.

Notice that Herschel’s observation of HJ 698 is also included here.   Click on the image for a larger view.

Notice that Herschel’s observation of HJ 698 is also included here. Click on the image for a larger view.

Surprisingly, S.W. Burnham didn’t include any comments on the mystery star either, even though he observed and measured HJ 697 twice:

Click to enlarge the image.

Click to enlarge the image.

Equally mysterious is how that star could have been missed with the apertures Burnham was using.   You’ll notice two notations in the fifth column from the left, which are explained on page iv of the second volume of his 1906 General Catalogue of Double Stars Within 120° of the North Pole.   β3 refers to the 18 ½ inch Clark refractor at the Dearborn Observatory in Chicago and β5 refers to the 40 inch Clark refractor at Yerkes Observatory.   You’ll also notice he lists “B” with a magnitude of 13 in 1878, but revised it to 11.7 in 1901, which matches closely with what I observed.

As to how the mystery star got there or where it came from, the most likely explanation is it’s a background star that was hidden behind the primary when Burnham made his observations. If there was ever anyone who put an eye to an eyepiece who could have detected that star, it was S.W. Burnham.   The proper motion of the primary is almost nil (+001 +015), but perhaps the mystery star has enough proper motion to allow it come into view in the hundred plus years since Burnham made his observations.

But to stir the mystery a bit more, I came across this 1999 photograph, which also shows the mystery star quite clearly.   In fact, its position relative to all three of the HJ 697 components matches those of Steve’s photo rather closely, even though there’s an interval of fourteen years between the two photos.

 HJ 697 1999 POSS II Band N, click to enlarge.

HJ 697 1999 POSS II Band N, click to enlarge.

So I’m not sure what to think at this point, except that the sky is a strange place. You never know what you’ll find lurking around the next celestial corner.

Many thanks to Dave Arnold for his reply to my email inquiry, to Brian Mason of the USNO for supplying data and answers, to Chris Thuemen for catching sight of a speck of light in his photograph, and to Steve Smith for definitively resolving that speck of light into a star.  Chris also introduced me to the Σ 700-ARN 63-WEB 3-HJ 698 area with one of his photos, which whetted my appetite for further investigation of those stars.

Next time out, as a result of inspiration provided by another reader of these pages, we’ll wander down to Canis Major and follow in the telescopic footprints left by Sir James South.

Clear Skies and stable seeing!   😎

Click on the image for a larger view!

Click on the image for a larger view!

A Tale of Two Tough Characters: Rigel and Tau (τ) Orionis

I’ve lost track of the number of times I’ve looked at Rigel, aka Beta (β) Orionis, but one thing that hasn’t escaped from my memory is the first time I viewed it in a 60mm refractor.  What stands out most clearly about that night was the moment I first caught sight of a flickering spark of light at the blinding primary’s southwest edge, something I really hadn’t expected to see.  That faint flickering spark was the 6.80 magnitude secondary, which is also double, although with a separation of only 0.10” I certainly didn’t notice.

I was reminded of that first 60mm refractor view of Rigel just a few weeks ago when I wandered just north of it to another difficult star, Tau (τ) Orionis.   Both stars are similar in their wide magnitude spreads, 6.50 magnitudes between Rigel and its BC secondary, and 7.30 and 7.40 magnitudes between Tau (τ)’s primary and the two stars that accompany it.  They both also boast of doubled up secondaries, but with the difference that the average backyard double star diehard has a fighting chance to wrestle Tau’s BC pair apart.

So in some ways this is a sojourn down one of the more difficult paths to double star nirvana, but it’s more a steady uphill climb than a hand-over-hand hoist to the top of a steep precipice.  After all, Rigel is very splittable with a 60mm refractor, although I can’t say the same for Tau (τ).  Nevertheless, difficult though they are, neither of these stars are really all that far out of reach, and both share one very important and redeeming attribute: they’ll sharpen your observing skills, provided you’re patient and are willing to persevere under a cold winter sky.

First, for those unfamiliar with the area, a chart displaying our destination:

You'll find Rigel and Tau (τ) holding down the southwest corner of Orion.  (Stellarium screen image with labels added).

You’ll find Rigel and Tau (τ) holding down the southwest corner of Orion. (Stellarium screen image with labels added).

We’ll wrestle with Rigel first and then we’ll give Tau (τ) a try.

Rigel  (Beta [β] Orionis)  (19 Orionis) (Σ  668)  (H II 33)
HIP: 24436   SAO: 131907
RA: 05h 14.5m    Dec: – 08° 12’
Identifier             Magnitudes       Separation      Position Angle     WDS
STF 668  A,BC:  0.30,   6.80               9.30”                  204°              2011
Bu 555       AD:   0.30, 15.40            44.60”                     1°                2008
Bu 555       BC:   7.50,   7.60              0.10”                    30°               2005
Distance: 773 Light Years
Spectral Classifications:  “A” is B8, “B” is B9

The challenge with Rigel lies in learning to see past its zero magnitude glare in order to visually excavate the seventh magnitude secondary buried there.  Every time I look at Rigel, I have to give my eyes time to adjust to that glare.

This sketch doesn’t quite convey the glare surrounding Rigel, nor does it do justice to the sudden visual and emotional impact of first sighting the secondary. But it’s close enough to give you a reasonable idea of what to expect. Nothing matches the real thing, though. So if you haven’t turned a telescope toward Rigel, time’s a wastin’! (East & west are reversed to match the refractor image, click on the sketch for a much better view).

This sketch doesn’t quite convey the glare surrounding Rigel, nor does it do justice to the sudden visual and emotional impact of first sighting the secondary. But it’s close enough to give you a reasonable idea of what to expect. Nothing matches the real thing, though, so grab a coat and a telescope and take a look. (East & west are reversed to match the refractor image, click on the sketch for a much better view).

Your first view is the hardest, not only because of the glaring battle you’re face to face with, but also because it’s hard to visualize what the secondary will look like in that glare.  More than likely your first sighting of it will sneak up on you unexpectedly, meaning you’ll suddenly discover you’ve been staring at it for several seconds without realizing it.  The first time I saw it I remember an eerie sensation – I had an uncanny feeling it had been looking back at me for quite a while before I recognized it for it was.  Weak as the secondary is in comparison to the primary (about four hundred times fainter), once your eyes have adjusted for the glare and that secondarial speck of light has registered in your brain, you’ll find it’s very sharp and very distinct.  There isn’t any guessing about whether you’re actually seeing something or whether your imagination is playing tricks, which has been my experience with Sirius.

Rigel  is frequently described as something of a training tool for visually sighting the secondary spinning around Sirius, which is accurate to a point — that point being the difference in the distinctiveness of the secondaries.  I’ve caught sight of the Sirius secondary (aka the “Pup”) several times this year, but each time I’ve been less than overwhelmed by the experience.  While sighting the Pup is a greater challenge, it’s a faint ghostly presence that plays tricks with your mind, whereas there isn’t any guessing about whether you’ve spotted Rigel’s secondary.  And there’s a good reason for the difference.  As of early 2014, Sirius “A” and “B” are separated by 10.1”, very similar to the separation of Rigel “A” and “BC”, but Sirius “B” is 9925 times fainter than Sirius “A”.

Now after you’ve wrestled Rigel into submission and are basking in the radiant blue-white primarial glory of your secondarial success, stop for a second and think about that secondary’s secondary  —  the “C” part of Rigel BC, the star that’s only 0.10” distant from “B”.  Think about the challenge of detecting an elongation in that BC pairing.

Impossible, right?  Not quite.

Not only was it done with a six inch refractor, but it was done twice.  In fact, the first hint that Rigel “B” was duplicitous was actually provided by a six inch f/15 Clark achromatic refractor.  And, not surprisingly, at the eyepiece of that instrument – both times – was none other than Sherburne Wesley Burnham.  He did get a slight break – apparently the separation of the BC pair was close to 0.20”, as opposed to 0.10”.

Click to enlarge.

Click to enlarge.

The full account of S.W.’s adventure is shown at the right, and it’s well worth reading.  As it turns out, the first solid confirmation came from the 36 inch Clark refractor at Lick Observatory (also an achromat), and even then it took several attempts, first because of poor seeing conditions, and second because the separation between the two stars apparently had narrowed to below 0.10”.  Note the magnifications required with that instrument, though – 2000x to 3000x!

So before you strenuously pat yourself on the back after your first success with Rigel “B”, pause to consider the level of visual skill wielded by Burnham.  Not that any of us will ever quite get there – and the pat on your back is well deserved, by the way – BUT, remember, there’s always another level of achievement to be had beyond your most recent one.

Like Tau (τ) Orionis.

Tau (τ) Orionis  (20 Ori)         HIP: 24674   SAO: 131952
RA: 05h 17.6m   Dec: -06° 51’
Identifier              Magnitudes       Separation      Position Angle     WDS
H V 25        AB:    3.60, 11.00             33.30”                   251°             2011
HJ 2259    AD:    3.60, 10.90             35.40”                     60°              2011
Bu 188      BC:  11.00, 10.90               3.80”                     51°              2011
Distance: 555 Light Years
Spectral Classifications: “A”is B5, “D” is G6

Located a mere one and a half degrees north and slightly east of Rigel, Tau (τ) Orionis is an experience of a different sort.  There’s less glare since the primary is over three magnitudes fainter than Rigel “A”, but there’s a wider magnitude separation between the primary and its two companions, “B” and “D”, which makes them about a thousand times fainter than the primary – and one of the stars is actually fainter than that.  The fact that they’re both almost four times further from the primary than the distance separating Rigel’s A-BC pair doesn’t seem to count for much in the advantage column.

On first glance, you’ll more than likely find a single star staring back at you.  But with persistent use of averted vision – and five or six inches of aperture – you’ll find this image gradually emerging:

 “D” will emerge first from the glare surrounding the primary, and with persistence and at least average seeing conditions, “B” will gradually make itself known on the primary’s opposite side.  The primary, by the way, is brightly white.  (East and west reversed, click on the sketch to bring “B” and “D” to life).

“D” will emerge first from the glare surrounding the northeast side of the primary, and with persistence and at least average seeing conditions, “B” will gradually make itself known on the primary’s opposite side. The primary, by the way, is brightly white. (East and west reversed, click on the sketch to bring “B” and “D” to life).

Even though Tau (τ)’s primary isn’t as bright as Rigel, it still throws off enough glare to make things difficult.  And despite the WDS data which shows only a tenth of a magnitude of difference between the two eleventh magnitude companions, “D” is noticeably easier to see than “B”.  I had to scoop up every photon I could find with my averted vision in order to keep “B” in view, and even then it had a nasty tendency to fade from sight.  Simbad shows “B” with a visual magnitude of 11.8 (compared to 11.0 for the WDS) and “D” at a visual magnitude of 10.9, which is more in line with what I saw.

And right there is the crux of a problem.

The WDS data shows the significantly harder to detect “B” companion as a William Herschel discovery, H V 25 – and it’s a little difficult to believe he would have cataloged that companion and ignored “D”, which is so much easier to see.  In fact, as it turns out, Herschel didn’t provide a position angle for the star he included in his 1780 description (twelfth title down):

Wm. Herschel on H V 25

.
.
In his 1906 Catalog, Burnham states the senior Herschel failed to see “D”, but that it was added by the junior Herschel, John, in his Fifth Catalogue . . . . . . .

Burnham on Tau Orionis

.
. . . . . . . so I dug out the entry in John Herschel’s Fifth Catalogue and found this . . . . . .

John Herschel on Tau.
. . . . . . . which isn’t a lot of help.   Even though that entry shows position angles and separations, none of them are reasonably close to either Burnham’s data or the current WDS data.  However it does show that John Herschel noticed the difference in magnitudes of the “B” and “D” companions, which again leads me to conclude the star William Herschel recorded in his observation is the brighter “D” on the east side of the primary, not the fainter “B”.

Enough of that.  There’s still a visual challenge we haven’t wrestled with yet, and that’s the BC pair.

Given how difficult it was for me to keep “B” in view, I wasn’t sure it was even worth the effort to attempt to pry it apart.  The seeing was poor – about a notch below average (a II on this chart) – and the glare from the primary was being magnified by a surplus of moisture in the air.  But with nothing to lose, I armed my six inch refractor with a 6mm AT Plössl  (253x) and finally detected a hint of an elongation – a very weak hint.  At that magnification, the primary was primarily a blob of unfocused light, and the image wasn’t helped in the least by a strong east wind that was making the visual observing life difficult.

So the challenge is still there to get a definite split from the BC pair, and it should be within reach of both a five and a six inch refractor given an atmosphere that’s willing to cooperate.  As temptation for what’s possible, here’s a photograph of the Tau (τ) system taken by Steve Smith which provides a good view of a distinctly separated BC pair.  It also shows quite clearly the disparity in magnitudes between “B” and “D”.

Photo used with the permission of Steve Smith, click to enlarge.

Photo used with the permission of Steve Smith, click to improve the view.

Credit for the inspiration to visit Tau (τ) goes to both Chris Thuemen, who sent me a photo of it hinting at an elongation in the BC pair — which in turn launched me on a long search for a good photograph of Tau BC — and to Steve Smith who went out and took the photo I was looking for.

As soon as the weather improves, the moon disappears, and the seeing cooperates, I’ll be back to tussle with Tau (τ) again.  If I can’t match the visual acuity of eagle-eyed S.W. Burnham, the least I can do is subdue Tau (τ) in order to get a taste of the satisfaction he must have felt when the elongation he saw in Rigel BC was confirmed.

Next stop – somewhere in the vicinity of Tau (τ).  Until then, clear skies!  😎

_______________________________________________________

Update: Giving into the “temptation for what’s possible.”

In the winter you’ve got to take the clear nights when they’re there, and when I finally found an unexpected one looming on the last day of February, Tau (τ) Orionis was still on my mind.  The seeing didn’t look any too great.  Sirius was doing what it’s done every clear night this winter, which is a polished imitation of an airport beacon flashing in red, green, and white — and Rigel was hard at work imitating it.  But I had already brought my 9.25 inch SCT out before dusk so it could cool down, and knowing Tau’s BC pair was going to demand plenty of aperture, I decided to see what would happen.   In the back of my mind, I was hoping a low magnification view would be enough to drive a wedge between “B” and “C”.

The seeing was pretty much what I expected — erratic, nervous, and even a bit blurred.   But with a 26mm Celestron Plössl at 94x, I could detect an elongated smudge of light radiating from the BC side of Tau (τ).  What really surprised me, though, was how difficult BC and D were to see in the primary’s glare, even with 9.25 inches of aperture.  But despite their battle with the glare, they were persistent enough to stay in view without resorting to averted vision.

Since I was having mixed success at 94x, I tried a 20mm AT Plössl (123x), which resulted in the same blurred elongation, but at least it wasn’t any worse.  Then I reached for an 18mm Radian, but somehow I managed to pick up the 14mm (175x).  “B” and “C” were now clearly separated — certainly not quite what you would call pleasingly precise points of white light — but once I realized I was seeing them at 175x, I decided to make one more determined seeing-defying leap to a 10mm Radian.  Using 245x on a night like this would normally be a sign of sitting in one place under a cold dark sky for too many hours, but since the night was still young, I convinced myself that since I didn’t expect anything more than unfocused blobs of bouncing light, I was still on the safe side of insanity.

Anyway, if you don’t try, you don’t know . . . . . . .

. . . . . . . and darned if those two blobs of light weren’t impossible to unscramble.

Esthetically pleasing they sure weren’t, but they were clearly separate:

This is what I saw, minus the blog effect, so don't be misled into thinking the view was quite this comfortable.   What it does do, though, is convey how much BC and "D" are subdued by the white primary's intense glare.   (East & west reversed to match the SCT view, click on the sketch to relive the experience).

This is what I saw, minus the blob effect, so don’t let the sketch mislead you into thinking the view was quite as comfortable as it appears. What it does do, though, is convey how much BC and D are subdued by the white primary’s intense glare. (East & west reversed to match the SCT view, click on the sketch to re-live the experience).

I had just a hint of what the inimitable eagle-eyed S.W. Burnham must have felt when he saw the elongation in Rigel’s BC pairing.  Subtle though it was, I stared at that dance of white light until my eyes began to cross.

And savored every single bouncing photonic moment of it.

A Tale of Two Secondaries: Part One — Bu 193

It’s not easy being a secondary on a short leash.  You live out your allotted hydrogen and helium burning years under the glare of your primarial parent, suffocating in its infernal glow, while yearning to shine separately in some remote dusty sector of the galaxy where you can set up house and raise a few planets of your own.  The best you can hope for is a passing stellar interloper with enough gravitational muscle to cast a few well-aimed gravity waves your way, giving you a chance to grab hold and surf your way to freedom.

And then there’s the impression you leave on that strange breed of earthlings known as Star Splitters.  Heck, most of the time they don’t even know you’re there, and when they do finally catch a glimpse of you, it’s only to record some obscure data that no one looks at for years — or worse, they confuse you with another star.  And even if you’ve managed to eke out a colorful existence, they only compare you to the more brilliant color of your primary nemesis.

To borrow a phrase from Sir Rodney of Dangerfield:  secondaries get no respect.

Maybe not — but they do have a few things to teach us.

** ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** ** **

Come along with me and I’ll take you to the far eastern fringes of Orion, where we’ll immerse ourselves in the mysterious interstellar expanse between Betelgeuse and the Rosette Nebula, and dig out an obscure triple star dubbed Bu 193 by that dedicated devotee of the difficult, S.W. Burnham.

 Here’s the wide view, showing the location of Bu 193 in relation to Betelgeuse and Epsilon (ε) Monocerotis.  Use Betelgeuse as a reference point to work your way to 4.40 magnitude Epsilon (ε) Mon, because that star will be our jumping off point to reach Bu 193. (Stellarium screen image with labels added, click to enlarge).

Here’s the wide view, showing the location of Bu 193 in relation to Betelgeuse and Epsilon (ε) Monocerotis. Use Betelgeuse as a reference point to work your way to 4.40 magnitude Epsilon (ε) Mon, because that star will serve as our jumping off point to reach Bu 193. (Stellarium screen image with labels added, click to enlarge).

And here’s the star hopper’s view.  From Epsilon (ε) Mon, move two degrees northwest to 5.70 magnitude HIP 29860 and 7.15 magnitude HIP 29780.  If you look south one degree from HIP 29780, you’ll see an arc consisting of four seventh magnitude stars (HIP 29618, HIP 29739, Bu 193, and HIP 29594).  Drop straight south from HIP 29780 to 6.60 magnitude HIP 29739, and you’ll find yourself less than half a degree north of Bu 193.  Slip south, center Bu 193, and pull up a chair.  (Stellarium screen image with labels added, click for a larger view).

And here’s the star hopper’s view. From Epsilon (ε) Mon, move two degrees northwest to 5.70 magnitude HIP 29860 and 7.15 magnitude HIP 29780. If you look south one degree from HIP 29780, you’ll see an arc consisting of four seventh magnitude stars (HIP 29618, HIP 29739, Bu 193, and HIP 29594). Drop straight south from HIP 29780 to 6.60 magnitude HIP 29739, and you’ll find yourself less than half a degree north of Bu 193. Slip south, center Bu 193, and pull up a chair. (Stellarium screen image with labels added, click for a larger view).

Bu 193                HIP: 29713   SAO: 113645
RA: 06h 15.5m    Dec: +03° 57’
Magnitudes   AB: 6.99, 12.38     AC: 6.99, 10.02
Separation    AB: 19.5”                AC: 57.8”
Position Angles   AB: 97°  (WDS 2000)    AC: 232°  (WDS 2011)
Distance: 1004 Light Years
Spectral Classifications:  A is B5, B is G3, C is A8

Now our primary focus here is on the secondary, the “B” of the AB pair, which is going to leave a faint, but lasting, impression on us.

Click to enlarge the view.

Click to enlarge the view.

In most cases, a distance of 19.5” from the primary would be enough to allow a secondary to be easily seen.  In this case, though, there’s 5.4 magnitudes of difference between the primary-secondary pair, in addition to which the secondary flickers at an almost futile magnitude of 12.38 — so sighting “B” is not for the faint of heart.  But since S.W. Burnham discovered “B” with his six inch f/15 Clark refractor (see the inset at the right — the link to the book is here), I figured I could do it, too, with my six inch f/10 Jaeger’s-lensed refractor.  So I gritted my teeth and went to work, well aware that I was in for a trying test of visual acuity.   And as we’ll soon see, there’s a lesson to be learned here from Mr. Burnham’s eagle-eyed artistry, and we’ll find it’s worth its weight in gold when we get further along to Tau (τ) Canis Majoris.

Let’s not ignore 10.02 magnitude “C”, though.  If you look closely at the data above, it would seem “C” should suffer from a relative disadvantage also, since it’s three magnitudes fainter than the primary.  But because it’s almost a full arc minute away, it manages to shine rather solidly on its own.  Or at least it does with four inches of aperture or more — I suspect it could be difficult with less.

Let’s take a first look at our target through an 84x lens:

 In a 40’ field, Bu 193 is surrounded by an attractive scattering of field stars, but in contrast, the area immediately around it is rather barren.  (East & west reversed to match the refractor view, click for a larger view).

In a 40’ field, Bu 193 is surrounded by an attractive scattering of field stars, but in contrast, the area immediately around it is rather barren. (East & west reversed to match the refractor view, click on the sketch for a much better view).

 Photo used with permission of Chris Theumen, click for a better view!

Photo of Bu 193 taken by Chris Thuemen and used with his courteous permission.  Click to enlarge the image in order to see “B”!

“C” is the first star immediately to the southwest of the primary, but “B” is nowhere to be seen in the sketch.  I looked long and hard, and finally managed a glimpse of it flickering at the edge of an averted gaze, but it kept drowning in the primary’s intense glare.   Judging from the visual distance separating “C” from the primary, I knew “B” was going to be uncomfortably close in my 84x view, but I was still surprised at how little space there was between that flickering ghost and its parent.  To give you some idea of how difficult it was to see the secondary, look very closely at Chris Thuemen’s photo of Bu 193 above (you’ll have to enlarge it).  You should be able to catch the weak glimmer of the secondary immediately to the right of the primary, which is slightly less difficult than my experience of it at 84x.

So let’s apply some magnification now and narrow the field of view down to about sixteen minutes of arc:

Insert Steve’s sketch:  And now “B” comes out of hiding!  It’s amazing what 9.25 inches of aperture will do (not to mention 261x).  Thanks again to Steve McGee for permission to use his sketch.  (East & west reversed, click on the sketch for a larger view).

And now “B” comes out of hiding!  It’s amazing what 9.25 inches of aperture will do (not to mention 261x). Thanks again to Steve McGee for permission to use his sketch. (East & west reversed, click on the sketch for a larger view).

And next, let’s zero in on a ten arcminute view and force the stars further apart:

 We’ve gone from 9.25 inches of aperture down to six, so “B” is a bit fainter now, but the view is tighter in this smaller field.  (East & west reversed once more, click for a larger view).

We’ve gone from 9.25 inches of aperture down to six, so “B” is a bit fainter now, but the view is tighter in this smaller field. (East & west reversed once more, click for a larger view).

We’ve eliminated most of the distraction from the field stars now and enlarged the view, which provides us with a rewarding contrast of the spacing between Bu 193’s three components (remember how close they were in Chris’s photo).  And we also have an opportunity here to gauge the visual impact of the primary’s seventh magnitude glare on the 12.38 magnitude secondary.  If you look to the left of the primary in the sketch above, you’ll see there’s another 12.4 magnitude star in this field (marked by the arrow at the left).   Although that star wasn’t visible in the first sketch above, you not only can see it here under the increased magnification, you can also see it stands out more clearly than the secondary.

And on the other side of the field, at the extreme edge (just slightly south of east), you’ll find two faint stars.  The fainter of the two (at the extreme right) is a 13.1 magnitude star which I found was slightly easier to see than the 12.38 magnitude secondary.  So in this particular case, as a rough approximation, the glare of the primary, when combined with the intervening 19.5 arcseconds of separation, reduces the magnitude of the secondary by about a whole magnitude.

Keep those comparisons in mind now, because they’re going to be very useful as we move on to Tau (τ) Canis Majoris, aka h 3948, which you can find  ➡  HERE.

Mad Meanderings under Temperature Inverted Skies

It’s been a looooonnng winter already.  Of course, if you go by the calendar, we’re only a month into winter.  But I tend to identify winter with the onset of the November rains, which typically don’t start here until the middle of that month.  This year, though, the rains were over-zealous, picking the middle of October to start falling from the skies – seventeen inches worth of falling in fact, in only the last two weeks of the month.  They were kind enough to take a short break in November, and even a couple of times in December.  But each time, the seeing was so poor it didn’t even deserve a place on a chart.

So when I saw a forecast for a string of five or six clear nights in the middle week of January – most of them moonless, even – I was as thrilled as a chocolate addict turned loose in a fudge factory.   That is, until I saw those two seemingly unrelated words:  temperature and inversion.  Put ‘em together and you’ve got astronomical problems.

Still, I adopted optimism as the best approach – and on that first night, as I looked up into a dark sky of gleaming stars twinkling with unrestrained abandon, I decided to turn the night over to my 100mm f/13 Skylight refractor, which has punched through poor seeing on many a mediocre night.

Not this time, though – mainly because the night was a whole lot worse than mediocre.

Polaris on a better night  (click for a larger version).

Polaris on a better night (click for a larger version).

Polaris, my first target, looked like it had had a bad hair night.  There were so many spikes exploding from its ragged almost-round edge I almost thought I was looking at solar flares.  Needless to say, the secondary was swallowed up in all that aberrant light.

I gave Jupiter a try, just to see if conditions were as bad in another part of the sky, and was treated to an amorphous blob of wobbling white light with occasional glimpses of what might have been a pair of horizontal lines running across it’s width.   It reminded me of a distant basketball bouncing on a stellar court, and I wouldn’t have been the least bit surprised to see the words Spalding or Wilson stamped across it.

Rats.

Since this was obviously pointless, I returned all the astronomical hardware to the house, pulled up the NOAA weather site to see what I could see, and found the atmospheric soundings over Salem, Oregon – which is about 100 miles from me as the crow flies – showed an air temperature of thirty-two degrees (F.) at 2200 feet of elevation, and fifty degrees at 5000 feet of elevation.  Even though Salem was trapped under a large cloud bank by the temperature inversion, and I wasn’t, I did have the thirty-two degree temperatures.  And that explained that.

So the next night, thinking I could sneak under the stellar radar by going smaller, I turned to my 80mm f/15 Mizar refractor, which has taken the twinkle out of many a dancing star.   Aber nein, as they might say in Deutschland, which translated means no way, not tonight, not last night, not tomorrow night, maybe not ever.

Twinkle, twinkle little star,
How rotten and despicable you are.
You’re gonna drive me to the nearest bar.

Back into the house again.

Now —– night number three:  clear and almost stable at dusk, clear and not stable at all an hour later, and  unclear, unstable, and totally un-thrilling a few hours after that.  I had even set up the D&G five inch f/15 in the unaccountably optimistic hope the sky conditions would improve.

Many words worse than rats rattled the air that night.

Which brings us to night number four.

I wasn’t going to try it.  At 7 PM, Orion’s belt stars were dancing like blinking white Christmas tree lights.  At 10 PM, they were still dancing, but I noticed the sky was incredibly sharp and transparent, despite being bathed with first quarter lunar light.  Tempting, yes – but no, no way — I’d had enough of dancing fuzz balls of spiky white lights.  Still,  I couldn’t resist taking a peek at midnight – and when I did, I noticed the dancing had dropped from the whirling dervish level to a mediocre mad prance.   Hmmmmm.

The Silver Streak, poised for action (click for a larger view).

The Silver Streak, a gleaming home-made 60mm f/16.7 refractor with a Carton lens, poised for action (click for a larger view).

The Silver Streak was sitting in the corner of the living room, it’s gleaming silver cylinder highlighted by a few beams of yellow-white moonlight that had found their way through the venetian blinds.   It was an alluring scene I couldn’t resist.  The scope was sitting on its mount, so I grabbed the whole affair with one hand, marched it out to the deck, set it down, and gave it some time to cool down to the forty degree temperature.

Since it was pointing at Orion, which had now started its downhill trek on the west side of the celestial meridian, I aimed at the Trapezium and discovered a blob of mostly un-focused starlight at the center of the nebula.  Ugh.  I panned up to Sigma (σ) Orionis and could barely recognize it.  Then I pointed the long silver tube up to Jupiter, and at least was able to recognize it was larger than a star – much larger, of course, and almost as unfocused.  Disgusted, I walked away from the scope and looked up at the sky.

How in the world could a sky look as beautiful as this one did, and still be such an infernal disappointment in a 60mm f/16.7 refractor?  Arghhhhhh!

Then, looking to the east, I spied Leo on an upward lope over the roof of my house, caught sight of Algieba, and decided to give it a try since it was in a totally different sector of sky.  Unsplittable it was in the 26mm Celestron  Plössl (38x) I was using, but almost binary-like in a 20mm TV Plössl (50x).  So OK, let’s take a gander at Polaris, I thought to myself.

Over to the north we went, the Silver Streak and I, and it was almost like old times!  Polaris was a sharp little dot of yellow light, and its ninth magnitude companion was a weak spark of barely breathing dim white light —  just like I remembered from those distant pre-rain soaked October nights.  What a sight for ravenous eyes starved for sharp pinpoints of exquisitely focused photons framed against a black backdrop!

Where to next, I wondered.  Back to Orion?  Well, why not, even though its belt still looked like a trio of slightly subdued white strobe lights.  The Trapezium hadn’t improved much, so I panned down to Iota (ι) Orionis.  And when I could get a precise focus — and when it would hold still — I was able to catch a very soul-satisfying glimpse of Iota’s (ι) 9.7 magnitude “C” companion.

So I slewed my way north to Sigma (σ) Orionis territory – again — and sat down with firm intentions of sitting tight until I could pry it apart, along with its delicate and fragile three-starred neighbor, Σ 761.  Now Sigma (σ) Orionis is a quadruple star, but the “D” and “E” companions are about all you can coax out of hiding with a 60mm scope – and that’s all I really wanted to do.  With some patient persistence and a heaping helping of averted vision, coupled with some focuser finesse, I got ‘em.

Companions in multiple-stardom -- Sigma Orionis is a quadruple (actually a quintuple to be exact, but the fifth star is out of our range), and Σ 761 is a genuine triple.  (East & west reversed, click for a better view).

Companions in multiple stardom:  Sigma Orionis is a quadruple (actually a quintuple to be exact, but the fifth star is well out of our range), and Σ 761 is a genuine just-as-you-see-it triple. (East & west reversed, click for a better view).

Meanwhile,  over on the left side of the eyepiece (northwest), where I had been casting an occasional curious glance, was Σ 761.  Delicate and fragile I said they were, and they are.  When I had first viewed them at the beginning of the evening, they were an inseparable blob.  But not now.

The 7.9 magnitude primary stood out distinctly at the top of the triangle it forms with the other two stars – no awards are won for picking that one out of the sky.   The trick – and it certainly is a trick in a 60mm refractor on a night of poor seeing – is to separate the 8.4 and 8.6 magnitude “B” and “C” companions.  The two stars just don’t lend a lot of light to the cause in a sixty millimeter lens — and the 8.5 arc seconds that separates the two stars may as well be half that distance for as difficult as they are.

So when I saw those wiggling half-white whispers of light as two separate, two ghost-like, two spectre-ously illuminated cotton-like wisps, I was thrilled right out of my Plössl pickin’ mind!  It was all I could do to stifle a rebel-like yell that would have raised every law-abiding citizen of this small coastal town six feet out of their bed in sheer terror.  Fortunately, I was able to wedge my fist firmly in my mouth and preserve their restful slumber.

When I finally calmed down and felt it was safe to remove my fist from between my teeth, I decided I would return to Algieba in hopes of being soothed into a stupor by its golden charms.  Leo was on his final approach to the celestial meridian by then, so I tilted the illustrious Silver Streak up into the southern sky, centered Algieba’s golden glow in the finder, peeked into the 20mm TV Plössl still parked in the diagonal, and allowed my right eye to be bathed by the warming rush of yellow-gold photons.  And, separate as separate can be, was that diminutive dot of green-yellow-gold secondarial light.

Ravished again I was.

Glowing in gold, and always a glorious sight to behold! (Click for a larger view).

Glowing in gold, and always a glorious sight to behold! (Click for a larger view).

Up to this point, I had resisted going beyond the 50x provide by the 20mm TV Plössl, but it seemed there might now be some room to maneuver the magnification higher, so I dropped a 17mm Faworski Ortho (59x) into the Silver Streak’s focuser and put my breathing on hold.  It wasn’t meant to be, though — that mere 9x increase in magnification was beyond the limits of the bad-seeing barrier.  What I found was two ir-rhythmically throbbing globes that wavered between almost round and half flat, the flat part being restricted to their bottom sides.   I’ve never quite seen anything like that – when they would go flat, both of them would be flat at the same time and in the same place.  As if the air had temporarily been let out of them.  Very  strange.  Inexplicably strange.

But at that point, I decided enough was enough.  It’s best to salvage what you can from a night like that one, and if nothing else, I had at least re-established a connection of sorts with the stars.

And although I hesitate to point out the obvious, I feel compelled to single out the humble contribution of Old Silver Streak and its twin lenses of achromatic delight.  Never — ever — under-estimate the ability of a sixty millimeter refractor!

Clear and STABLE skies!  😎

And now for something totally different — a Refractor Review!

A few months ago, a remarkable 100mm refractor found its way to my front door and landed in my hands.  Now it’s no secret that long focal length refractors attract me like a moth to a front porch light, but in this case there were a few other factors involved — such as a long black tube, a gleaming brass dew shield and finder, and above all else, the aura of 19th-century England which surrounds it in the same way an elliptical galaxy is encircled by a glowing nebulous cloud of stars.  For those not familiar with the age, the late nineteenth and early twentieth century was an era when high quality achromatic refractors, crafted by Thomas Cooke & Sons in England and Alvan Clark & Sons in the United States, ruled in many observatories in both countries and in continental Europe.

So to get to the point, I was asked by the person who hand-crafted that refractor, Richard Day of Skylight Telescopes, if I would be interested in doing a review for Astronomy Technology Today — and the rest is now history.  The review has been published in the current issue (March-April, 2012) of that magazine, along with an account by Richard of how he became involved in the art of building hand-crafted refractors.

With the blessings of Gary Parkerson, the editor of the magazine, I’m posting my original draft of that review here.  If you have a subscription to the magazine, you can download a .pdf version of either the entire current issue, just my review, or even Richard’s piece, by going to the ATT website.    But — you need to be a subscriber to have electronic access to the magazine — and,  if you’re not, you can subscribe to the digital edition for the current  reduced rate of ten dollars.  I’ve been a subscriber almost since the magazine first came out in 2007, which should say all there is to say about my high opinion of it.

So ………. without further ado, and a little inspirational help from the gracious and very dependable Admiral William Henry Smith …………..  here we go!

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The Skylight 100mm f/13 Refractor: A Different Experience

Rats! Rain and more rain! Enough to drive a starlight addict into a photon deprived fit!

I sat back in my chair, opened my well worn star atlas, and began to plot new paths through the double star studded heavens as the rain beat against the windows and the wind rattled the doors and roared through the trees — again.  Let’s see now, this is day nineteen — twenty-one more to go and we’ll reach forty.  Maybe I better get back to work on that ark I started last year.

I worked my way across the middle of Gemini, and then down into northern Orion, circling and plotting as I went, making lists of magnitudes, separations, and position angles, and then laid my notes aside, closed my eyes, and began dreaming of clear dark skies filled with jewel-like points of starlight ……………

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

……………  And then I heard the sharp scrape of a chair being dragged across my observing deck, just outside the window. I jumped up, walked over to the door, opened it carefully, and peered into the moonlit darkness — and over in the corner where I normally set up my telescope, I saw a figure in an old black frock coat, wearing a tri-cornered hat and holding a long-stemmed pipe, peering intently into a highly polished black tube with a gleaming brass finder just a few inches from his hat-covered head.

Hmmmmm, I hummed — that guy looks vaguely familiar, even a bit like the much admired Admiral William Henry Smith of mid-nineteenth century British astronomical fame.

I grabbed a coat, walked outside, and quietly started toward him. As I got closer, he looked up from the eyepiece, with blue-white starlight sparkling in both eyes, and in a heavy nineteenth century London accent with an aroma of sea salt hovering about it, said, “Something I can do for you, m’good man?”

“Yes, you can,” I began hesitantly.  “You can start by telling me who you are, and how you got here.”

He stood up, took off his hat, and with a low bow and a flourish of his coat, said, “Allow me to introduce m’self, m’dear sir.  I am the good Admiral Wm. H. Smyth, well known author of that best selling 1844 compendium of the stars, A Cycle of Celestial Objects, of which you twentieth-first century folks typically peruse only the fragment known as The Bedford Catalog!”

. . . the brilliant white light of the moon was busy beaming its bright rays off of a beautiful brass dew shield.

“I thought that might be the case,” I replied a bit distractedly, still wondering how he got here. It was that telescope — I couldn’t take my eyes off of it. The long, gleaming black tube literally shimmered under the brilliant white light of the moon, which was busy beaming its bright rays off of a beautiful brass dew shield.

“Mind if I take a peek into that thing?” I inquired.

“Certainly not, m’boy! Please, peer into this heavenly one hundred millimeter instrument!”

I positioned my eye carefully in front of the eyepiece, reached for the focus knob …………………

…………….. and suddenly a strong gust of wind rattled the entire house and sent a refractor length tree limb crashing into the deck. I shook myself out of my stupor, looked around in a slight daze, got up, walked over to the door, opened it, and looked outside —- nothing there but a large limb over in the corner of the deck where I normally set up my telescope.

Very strange. I ought to know by now not to eat oysters and sardines this late at night.

That long black tube, with the gleaming brass dew shield, and the brass finder ............. there it was!

A few nights later — it was still raining, and the wind was still blowing, and I was scrupulously avoiding the sardines — I was inspecting the internet for possible purchases of an astronomical nature, and suddenly I felt my breath catch.  That long black tube, with the gleaming brass dew shield, and the brass finder ………….  there it was!  The telescope in my dream!

I didn’t hesitate for a tenth of an arc second.  I placed the order, and three days later it arrived in a large brown truck and was carried up to the front porch while I stood in stunned silence.  Under clear skies, even.

Now, the truth is, when I placed that order, I was a bit more than a bit concerned about a telescope of that length surviving the journey from London to southern California to Oregon. So I opened the stout outer box very cautiously, then a similarly stout inner box, and removed enough molded foam and bubble wrap to float that ark I never finished all the way to Hawaii.  Very impressive work.

Finally, after what seemed like a short version of eternity, I lifted a long bubble-wrapped tube out of the box.  And then I saw it — a red sheen on the other side of the bubbles! A red scope? I thought this thing was supposed to be black!

Slowly, carefully, cautiously, and with my cup overflowing with concern and curiosity, I unwound the crackling bubble wrap — and there, beneath all of it, was a bright red blanket wrapped carefully around the entire length of that long tube! Nice touch!

I unwound it, too, and carefully as well, and as I did, the long black gleaming tube and shining brass dew shield of my dream emerged into the admiring low afternoon daylight of northwest Oregon.

Inside the box I found a Baader Steeltrack focuser and that glowing brass finder I had spied in the moonlight when the Admiral was visiting. It didn’t take long to attach either of those, followed by a pair of Parallax rings I ordered separately, then my dovetail plate, and then  ……….. with visions of frock coats, tri-cornered hats, wool vests, and the remembered aroma of pungent tobacco wafting my way from the Admiral’s long-stemmed pipe, I hoisted the whole thing on to its mount, edged the dovetail carefully into the saddle, tightened the knobs, and proceeded to stand back in admiration  …………. and stared  ………..  and walked around to the other side  …………  and stared  …………  and walked to the front  …………  and stared  ………..  and then to the back  ………..  and, well,  ………….  I stared.  A lot.  While walking in circles.

The photos I had looked at on the internet were good, but not as good as this. The admirable Admiral was right — this was heaven.

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So how does it perform?

Imagine the delicate strains of the Second Movement of Chopin’s Second Piano Concerto drifting across an open field on a late summer afternoon in early September, while the slanting rays of a low sun stream through the dappled rustling leaves of a tall stand of poplars.  Sublime it is.

Being that the skies were clear and cooperative that night, I lined up the mount and that long black tube on Polaris, and initiated my one hundred millimeter Skylight f/13 into the world of multiple star light.  With an 18mm Radian (72x) perched proudly in the diagonal, I gingerly dialed in that first light focus — and there was that beady little gleam of ninth magnitude secondarial light, looking me right in the eye from a jet black sky.  I could hear the Admiral’s voice again:  “Please, peer into this heavenly one hundred millimeter instrument!”

The waxing moon was out that night, shining at about 70% of full power.  Ignoring it for the moment, I swiveled the long black tube through that shimmering moonlight to the Orion Nebula just to take a peek.  I bent down to the finder, watched the three gleaming pools of light that decorate Orion’s sword come into view, put the center pool under the crosshairs, and then sat down and leaned over to peer into the 18mm Radian.  Despite the moonlight, the nebula stood out almost as if it was three dimensional.  The contrast was simply amazing — shades of light and dark gray ran randomly through the center and out to the edges — and there was just a very slight hint of color, dark red, dark pink even, very subtle, and beautiful beyond description.  And the four stars of the Trapezium looked like they were etched into crystal.  Wow.

There are two double stars in the vicinity of M42 that I’ve been eyeing periodically over the last few years, which can be a challenge for a four inch scope.  One is Σ 750, located at the north edge of that northern pool of light (NGC 1981).  The magnitudes of that one are 6.4 and 8.4, with a short 4.2″ of distance between them.  The other one, Σ 754, is at the southeast edge of the southern pool of light (NGC 1980), and it has magnitudes of 5.7 and 9.3 separated by 5.3 seconds of arc.  Both can be a bit difficult because the secondaries are mere phantoms of light that tend to suffocate under the glow of their primarial parents.

At 72x, each of those elusive secondaries was as distinctly separate and pinpoint sharp as could be.  There were no intermittent bursts of ravenous photons leaping from the primaries with intentions of swallowing the secondaries — just round, sharply defined primarial orbs with very delicate micro dots of white light perched impossibly close by, shining sharply on their own.  I sat and stared at each of them for about fifteen minutes.  Then I went back and forth between them several times — I simply couldn’t believe I was seeing what I was seeing at that relatively low magnification with no strain to my visual apparatus.  I’ve seen them like that in a five inch refractor at similar magnification, but not in a four inch.  Pure gold.  Pure undiluted, unaltered, unbelievable gold.

When I recovered, I scanned the sky in search of old favorites, and never met with anything anywhere near disappointment.  Sitting at the rear of that immaculate gleaming black tube with the moonbeams bouncing from the brass dew shield, I was ready to sell every scope I own and live happily ever after with just this one.  I can’t ever remember a reaction like this to a telescope.

Now I’m not going to rattle off esoteric mathematical formulas and phrases here.  I know optical gold when I look through it.  I checked the collimation that first light evening, first with a Cheshire tube — it was dead center — and then toward the end of the night on several first magnitude stars.  I looked closely at the in- and out-focus images of each of them and detected what might be a very slight over-correction, but if so, I wouldn’t touch this lens for all the Naglers in a Televue warehouse.

What about that dreaded two letter designation for color, CA?  Not much, I can tell you.  Jupiter shows a slight bit around the outer perimeter when out of focus, none when in focus.  That bright, 70% illuminated lunar orb flashed a bit of yellow around the edge, but just barely — I had to look for it to catch it.  The detail along the terminator was sharp, the shadows were jet black, and the rough edges of craters had that granulated texture which is characteristic of sharp optics.  There were flashes of color when Regulus was out of focus, but almost none when it was focused precisely.

Plastic plug? Nein! How about brass instead?

The only aspect of this beautiful refractor I can point to with any concern is the coarse focus adjustment on the Baader Steeltrack focuser.  It’s much too stiff when attempting to coax it into motion from a standing start.  That can be adjusted out, although it would be a huge help if Baader would get a data sheet on their web site with adjustment information.  But the fine focus knob is as smooth as a sharp knife passing through a succulent oyster, and contributed immensely to my success with the two double stars described above.  And it’s a very heavy duty piece of equipment that should easily hold a large two inch diagonal and a monster eyepiece, such as the 31mm Nagler or the 21mm Ethos.  I had a very heavy two inch Takahashi diagonal plugged into the focuser, and at one point I loaded it with a 5mm Radian, pointed it at the zenith, and it held firmly in place.  No horizontal sag, no vertical slip.

Oh, and one more thing about that focuser.  You know the little white plastic plug that fits into the end of the 1 1/4″ adapter?  Not on your life.  How about a heavy brass plug.  Neat.

As I’m writing this, the infernal rain has returned, and the starlight I’m addicted to is hiding on the other side of the scudding gray clouds streaming past overhead.  So I think I’ll amble over to my comfortable old chair, plot a few more courses through the heavens, and then lean back, close my eyes, and see if I can get in touch with the good Admiral once more.  I need to find out where I can get a black frock coat, a tri-cornered hat, a wool vest, and a long-stemmed pipe.  I’ve got an old stash of Whitehall tobacco I’ve been saving for a long, long time, waiting for the right moment — and I do believe I’ve finally found it.

Clear Skies!