• Choose a post by category or constellation

  • Learn the Night Sky

  • Search strategies

    Use the Search box below to find doubles by popular name, RA, or telescope size. For example, a search on "15h" will find all doubles we've reported on that have an RA of 15 hours. A search for "60mm" will find all doubles where we used that size telescope.

Cavorting with Caph, Part 3 – ARG 1, SMA 3/STI 8, Bu 254, HJ 1008, KR 4, HJ 1012/1013

In this final segment of our three-part excursion we’ll close the Caphian circle with an interstellar voyage through its northwest and northeast quadrants.  If you missed the previous chapters in this adventure, we spent the first evening with Caph’s closest relatives right here, and our second night out we explored the southeast and southwest sectors surrounding Caph, which can be found over here.

You may have seen this twice before, but since the third time is reliably rumored to be a charm, here’s another look at our finder field for easy reference:

This is a correct image finder view of Caph and it’s immediate confines, with the diameter of the circle being about three degrees . . . . . . but we’ll restrict our meanderings to within about 1.5 degrees of Caph’s golden-yellow charms. (Stellarium screen image with many, many labels added — click for a full screen view).

Let’s begin again with Caph centered in that correct image finder shown in the chart above.  If you cast your glance about half a degree due north of Caph, you’ll spy the shimmering 6.71 magnitudes of HIP 860/SAO 21160.  We’re going to wander over in that direction, but don’t move yet because I’ve got precise directions for you.  Trust me — you can get turned around here so fast you’ll think you’ve been pulled through a worm hole into an alternative universe.

With Caph captured at the center of your finder, lean down to the eyepiece and make sure it’s centered there as well.  I’m using a 10mm Radian in a six inch Celestron f/8 refractor, which provides 152x and a field of view of about half a degree.  We need that much magnification because some of the stars on our list are what you might call elusive — a nice way of saying they’re darn hard to identify.  Whatever combination of scope and eyepiece you’re using, if you can get close to the magnification and field of view I’m using, you’ll find the directions I’m going to provide will work rather well.

And before you move at all, here’s the data on the first pair of stars on our agenda:

ARG 1              SAO: 21134     (No HIP number)
RA: 00h 09.1m   Dec: +59° 38′
Magnitudes: 9.7, 9.8
Separation:  25.9″
Position Angle: 329°  (WDS 2008)
Distance: 400 Light Years
Spectral Classification: A2, K

SMA 3/STI 8          (No HIP or SAO number)
RA: 00h 08.2m  Dec: +59° 33′
*****            Magnitudes         Separation        Position Angle          WDS
SMA 3       AB: 12.2, 12.4               9.3″                        33°                    2001
STI  8        AC: 12.2, 14.2            13.7″                      356°                    2001
STI  8        BC: 12.4, 14.2              8.4″                      314°                    2001
STI  8        BD: 12.4, 13.6              8.5″                      158°                    2001
Distance: ?????
Spectral Classification: ?????

OK — with Caph centered, you are hereby cleared to move north.  As Caph slides out of view at the south edge of your eyepiece, our first star, ARG 1, will come into view at the north edge of the field.  The distance from Caph to ARG 1 is 30 arc minutes — the same as the eyepiece field of view!  See how well that worked?  And after you’ve centered ARG 1, if you look closely — and I do mean closely! — you’ll see SMA 3/STI 8 in the southwest part of the field.

And here’s what you’re looking at:

Quite a scattering of stars here, so you really have to scrutinize the field to find what you’re after. Fortunately, the two components of ARG 1 are brighter than most of the stars in the field. (East & west reversed to match the refractor view, click on the sketch for a larger and clearer image).

Now that wasn’t really all that bad, was it?  Imagine trying to identify these stars on your own on the first attempt — you might say what I said:  ARG!  And if you’re wondering where that identifier came from, so am I.  It may be a reference to Friedrich Wilhelm Argelander, but the WDS date of discovery (1901) is after Argelander had passed from the scene (1875) — so there could well be another explanation, too.

But now that we’ve captured these stars in our eyepiece, let’s not be rash and rush off.  It always pays to survey the surroundings.

The 9.7 and 9.8 magnitude glowing globes of ARG 8 stand out rather well in this field since their only competition comes from 8.9 magnitude SAO 21152, which is resting quietly down in the east quadrant of the eyepiece.  ARG 1’s secondary should radiate a bit of an orange or deep yellow glow since it’s a class K star, but I never saw it, probably because the white light emanating from the primary has wrestled it into a subdued state.

What I found most intriguing in this field of view was that dim collection of mid-12th magnitude stars labeled as SMA 3/STI 8.  The ember-like stars fluctuate rather coquettishly in and out of vision, playing hide-and-seek with the averted eye,  most likely a function of their faintness.  I could pick out the three brighter embers most of the time with little effort — they were knotted into a distinct trio — and I think I caught sight of the 14.2 magnitude “C” component a few times.  I could never be sure, though, so I left it out of the sketch.  Even though that trio of wavering stars is dim, the sum total of all their dim ember-ous light is more than enough to make that 14.2 magnitude star a real challenge.

By the way, if you search for this collection of stars in the Washington Double Star Catalog (WDS), you’ll find it under STI 8.  You have to look in the notes section to find the AB pair is also labeled SMA 3 — or you can look here as well.

As for those strange identifiers, SMA and STI, the owner of the initials SMA is described here, while STI is covered here.

Now before we move on, feast your eyes on this photo for a few moments:

(STScI Photo, east & west reversed to match the refractor view, with north at the top).

Caph’s exuberant glow is just out of sight at the bottom left of the photo, and due north of it you can see our current ARG 1 location.  Just barely beyond SAO 21152 at the east edge of our field of view, further east and slightly north, is 6.7 magnitude HIP 860, which is beaming brightly in the photo.  So move SAO 21152 toward the center of your eyepiece, watch HIP 860 come into view, and then move it to the center of the field.  With it centered in the field, you’ll see Bu 254 in the northeast corner of your field of view – it appears as an eighth magnitude single star.  Center it, and I’ll prepare you for it by showing you the data:

Bu 254                SAO: 21188     (No HIP number)
RA: 00h 11.6m   Dec: +59° 45′
Magnitudes    AB: 7.9, 11.90     AC: 7.9, 12.6
Separation     AB: 7.1″                AC: 37.0″
Position Angle     AB: 237°  (WDS 2008)    AC: 240°  (WDS 2008)
Distance: ?????
Spectral Classification: G8

This one is tough.  I skipped right past it more times than I care to admit, and even after I finally pinned it down, I missed it again the next time I went in search of it.  The problem is this sneaky triple star sports that characteristic Burnham-ian bias towards the difficult.   That’s because there’s a difference of 4.7 magnitudes between the primary and the “C” component, which also means that 12.6 magnitude tertiary version of a stellar furnace is about seventy times fainter than its primarial relative.  Factor in that fast fading magnitude of 12.6, and it’s really even more difficult than that.  And although the secondary is seven-tenths of a magnitude brighter than “C,” it’s also five times as close — which means it’s really an ocular nightmare to crack.

But nothing in this universe of ours is really worth doing unless it’s done well — which in this case requires so much effort it leaves you lying limp on the observing deck-ground-or-floor, gasping for air.  So after gasping my way back to an arid second wind, I pulled myself up to the telescope with both hands and persisted in persisting some more —– and just prior to reaching the gasping stage again, I saw this:

Success !!!   And whew, too. (East & west reversed once again, click on the sketch for the larger view).

I must say, it’s a thing of real beauty.  Of course beauty is in the eye of the beholder, and after my gold medal marathon effort, my eyes were more than eager to behold some beauty.

The secret of success was locked up in the 7mm orthoscopic eyepiece I assigned to the task, which I believe is a microscope eyepiece converted to an astronomy eyepiece by Sheldon Faworski.  It was endowed with an uncanny edge in this particular adventure, since my other old reliables couldn’t quite catch the elusive secondary.  But there just absolutely is no accounting for what will work on a given night.  As Mr. Spock said more than once to Cap’n Kirk: “It’s illogical, Jim.”

Shifting over to an historical perspective, S. W. Burnham came across both the “B” and “C” components of this star in 1898 using the 9.25 inch refractor at the Dartmouth Observatory, but he wasn’t the first to find them.  Baron Dembowski recorded an observation of the “B” companion in 1875, and “C” was seen in 1893 by H.C. Wilson with a sixteen inch instrument from the Goodsell Observatory in Northfield, Minnesota.  (See p. 2 of this book).

OK, time to move on.  Make sure you have Bu 254 centered in your eyepiece field of view, coax it over to the west edge and then out of sight, and if you’re still using an eyepiece with a 30′ field of view, you’ll see our next selection of stellar light come into view on the opposite side, which is HJ 1008.  Total traveling distance from Bu 254 to HJ 1008 is 28 arc minutes if you’re logging mileages.

HJ 1008                   SAO: 21249   (No HIP number)
RA: 00h 15.2m   Dec: +59° 47′
*****             Magnitudes           Separation        Position Angle          WDS
HJ 1008    AB:   8.1, 11.3                 21.7″                     125°                   2007
ABH 2        AD:   8.1, 13.1                78.9″                     147°                   2007
ABH 2        AE:   8.1, 14.2              106.2″                       58°                   2007
ABH 2        AF:   8.1, 14.1                 58.7″                     341°                  2007
ES 1          BC: 11.3, 13.0                 10.1″                     227°                  2007
Distance: ?????
Spectral Classification: A4

If you ogled the photo above carefully, you had just a mere peek at the clustered nature of this star, which is also suggested by all the components listed in the data lines above.  You need at least five inches of aperture — six is certainly much better — to bring out all the detail in this unique little beauty.  And surprisingly enough, those two 14th magnitude stars, “E” and “F”, are not as elusive as their weak wattage would indicate.

Let me show you what I saw — and make sure you click on this sketch to enlarge it to full size:

They’re all here — and they’re all alone in the center of the field. And their geometry is pretty close to perfection, too. (East & west reversed, click on the to ENLARGE it!).

It took several approaches before I found a night with an atmosphere willing to cooperate long enough for me to study this photon emitting formation.  You need at least average seeing and average transparency (we’ll call both a III on this scale) to separate all the members of this shimmering sextuplet, plus a sharp eyepiece and a healthy dose of patience.  Fortunately I was permitted a couple of hours of grade IV seeing early one morning, which allowed me to put the last piece of the puzzle in place, the dimly separated BC pair.

There’s an unlabeled star to the southwest of the primary (at about the same distance as “D”), which completes the quadrilateral figure surrounding the primary and the BC pairing — sort of a force field that has successfully held the other dim stars in the field of view at bay.  It really is a unique view, but it takes a strong application of magnification before it emerges from the inky darkness. And it’s well worth the effort, especially early on a quiet morning when the only company you have is an ocean purring away in the background.

With HJ 1008 still centered in the field, shift it slowly over to the west edge of your eyepiece, and as you move it out of the field of view, our next star, KR 4, will enter the scene from the south.  Look for two very close eighth and ninth magnitude stars with an orange tint.  Total traveling distance is 32′.

KR 4                        HIP 1543   No SAO number
RA: 00h 19.2m   Dec: +59° 42′
Magnitudes: 8.2, 9.4
Separation:  2.2″
Position Angle: 179°
Distance: 520 Light Years
Spectral Classification: F0
Discovered by A. Kruger in 1890

Rather a sparse field, to say the least! Look just below and to the left of center to spy the weak orange glow of KR-4’s twin stars. (East & west reversed, click on the sketch for a larger version).

There is just something about two very closely separated faint stars of similar magnitude that I find to be visually riveting – and KR 4 was no exception.  I was smitten by its two distinct dots of orange-tinged light from the moment I inhaled their dual beam of photons.  They sure don’t have much stellar competition, but the dim asterism KR 4 forms with the other three stars in the sketch really caught my attention.  And the KR 4 pair is much easier to separate than their 2.2″ of distance and marginally faint magnitudes would lead you to believe.

The star at the west corner of the field, A 905, consists of a 9.7 magnitude primary and a 10.5 magnitude secondary with a separation of .60″ (WDS 1994), well out of my range.  R. G. Aitken is credited with its discovery in 1905.  The other two stars in the field have magnitudes of 13.2 (northwest corner) and 12.2 (east corner).

And now, allow KR 4 to slip slowly to the north edge of your eyepiece field of view, and as it gets close, you’ll see an eye-catching collection of stars enter from the south.  There’s only 18 minutes of arc separating KR 4 and HJ 1012/1013, so they’ll both fit in the 30 arc minute field of view if you’re still using an eyepiece that falls in that range.

HJ 1012 (STI 1320) / HJ 1013                (No HIP or SAO numbers)
RA: 00h18.8m   Dec: +59° 23′
*****              Magnitudes          Separation        Position Angle          WDS
HJ 1012     AB: 11.3, 11.7              14.50″                    350°                   2001
HJ 1012     AD: 11.3, 12.1              60.10″                    116°                   2001
HJ 1013    CD: 11.9, 12.1              14.10″                    328°                   2001
Distance: ?????
Spectral Classification: ?????

The first time this field of stars sauntered into view, my eyes immediately gravitated to the trio of seen in the sketch below in the east quadrant of the field (and again, click on it to enlarge it!):

A dim and delightful Cassiopeian double-double shadowed by an unrelated arc of stars to the east.  (East & west reversed once more, click for a much better view).

That puzzled me at first since I was looking for four stars, not three — and then I spied my prey in the west corner of the field.  But I was so taken by that initial impressionable view that I included the entire starry scene in the sketch – those three stars really add quite a unique kind of punctuation to the view.  Their magnitudes, from south to north (left to right in the sketch), are 9.8, 11.3, and 11.8.

Sir John Herschel gets the credit for prying this quadruple collection from the sky — really a dim double-double if ever there was one — in 1828, using a twenty inch reflector.  A man of few words who seldom included any comments in his observations, he left us with these three words — “A neat pair.” – which in his lexicon is high praise, indeed.

And a neat double pair they certainly are. I really don’t think I’ve ever seen anything quite like them when you factor in their faint magnitudes.  But with five or six inches of aperture, and a magnification in the 150x to 200x range, all four stars are very easy to see.

To put a flourishing final touch on this delightful Caphian banquet, your star-splitting chef highly recommends bringing KR 4 back into the field and parking it on the north corner of your plate.  Then feast your eyes on the four-starred beauty of Sir John H’s “neat pair” for several minutes, linger over the delectable curve of that trio of tenth and eleventh magnitude stars on the east edge of your dish, and finally, wash it all down with a long, thirst quenching draught of KR 4’s orange radiance.  And after you feel a wave of refreshed bliss wash over you, sit back in your chair, raise your star-saturated eyes to Cassiopeia’s sparkling “W” — and thank your lucky stellar orbs for the great good fortune of being in the right place at the right time.

Bon Appétit, mein Herren und Damen . . . . . . . and Clear Skies!   😎

Advertisements

2 Responses

  1. Hi John!
    A really fine safari around Caph. Just having a drink to flush the grit from between my teeth. What I really need is the abridged version to take into the field next week-end. Going to join a couple of buddies to do some observing.They will be doing a meteor watch while I do the circum-navigation of Caph. I really enjoyed the link to William Marshall Smart…another history lesson on how the Scottish got there penny pinching character trait. I have always lived by the dictum…if you haven’t got the cash in your pocket you don’t deserve it!

    Keep up the great work!

    Cheers, Chris.

  2. Actually, I just happen to have an abridged version of the third tour (which I sent to Chris last night), which I’ll add here. It consists of directions from Caph to each of the the stars in the third tour, plus a summary of the distances.

    These are based on using an eyepiece with about a 30 arc minute field of view, so if you stick close to that, you’ll see the stars appear at the edge of your incoming field as described.

    Directions:

    1. Center Caph, then move north, sliding Caph out of view at the south edge of the eyepiece. ARG 1 comes into view at the north edge. SMA 3/STI 8 can be seen in the southwest part of the field.

    2. SAO 21152 (8.9 magnitudes) is visible in that same field, to the northeast of ARG 1. Center SAO 21152 and you’ll see HIP 860/SAO 21160 (magnitude 6.71) come into view. Center it, and you’ll see Bu 254 in the northeast corner of the field. There’s a wide pair of stars (magnitudes 10.7 and 10.9) to the west of the line that runs from HIP 860 to Bu 254, which can be misleading. Bu 254 is very tight, and the companions are very faint and hard to see in its glow.

    3. Center Bu 254 and then move it to the west edge of the eyepiece and out of view. After it disappears, HJ 1008 comes into view.

    4. Center HJ 1008, then move it to the west edge of the eyepiece, and after it leaves the field, KR 4 comes into view, just south of the center of the field.

    5. Center KR 4 and move south. HJ 1012/1013 comes into view while KR 4 is still visible on the north side of the field.

    Distances
    Caph to ARG 1: 30′
    ARG 1 to HIP 860: 10′
    HIP 860 to Bu 254: 8′
    Bu 254 to HJ 1008: 28′
    HJ 1008 to KR 4: 32′
    KR 4 to HJ 1012/1013: 18′

    Easy as pie. :mrgreen:

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: