| Richard Harshaw | ||||
| Star:
Bur 975
Date & Time: 6 July, 2001, 03:00 to 04:55, UT Seeing: 8 <1-10 Seeing Scale (10 best)>. Transparency: 6-7/10 ,variable, due to high hazy clouds Location of site: Northern Kansas City, Missouri. 39º 15' N, 94º 30' W, 980 ft above Mean Sea Level Site classification: Suburban Sky darkness: <Limiting magnitude> Telescope: Celestron C-11 Eyepieces: 25mm Plossl, 9mm Lanthanum Magnification: 112x, 311x |
Bur 975 (OS 367 rej; Hough
648 (a))
Position: 1915+3434 Magnitudes: 7.2 (F5 IV), 12.7, 9.7, 9.7 Sep/PA's: Aa- 21- / 74+, AB- 33- / 228=, AC- 0.9+/261+! Year of this measurement: 1998 Colors noted: W, ?, O?, ? Comments: Observed
at 112x where "a" was suspected. At 311x, "a" was confirmed.
The BC split was very difficult, only being cleanly split at moments of
exceptional seeing.
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| William Schart | ||||
| Star:
Bur 975
Date & Time: July/9/01 0500 to 0635 UT Seeing: 7 <1-10 Seeing Scale (10 best)>. Location of site: Killeen, TX, USA Site classification: Suburban Sky darkness: 4 <Limiting magnitude> Temperature: In the 80's F (30's C). Slight breeze. Telescope: Celestar 8" SCT Eyepieces: 25mm, 17mm, 10mm Magnification: 80x, 120x, 200x |
Very tight and faint. Just
an elongation at low power. Split at mid powere and confirmed at high power.
I would however say that the best view was at mid power.
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| Bob Hogeveen | ||||
| Star:
Bur 975
Date & Time: 26 July, 2001, 00:00 Seeing: 6 <1-10 Seeing Scale (10 best)>. Location of site: Annen, The Netherlands - 53N, 6E Site classification: Village backyard Sky darkness: 4 <Limiting magnitude> Telescope: Celestron C-11 Eyepieces: Ultima 30mm , LV 15mm, 7mm Magnification: 93x, 187x, 400x Harshaw Scale: 4 <1-5; 1 best> |
This double puzzled me.
What I did see was a very wide pair, corresponding with OS 367 (7.2 - 9.7
33"). And there was nothing else... No Aa, no BC. Even at 400x I could
detect no signs of doubleness with either stars. This was confirmed by
Skymap because Tycho/Hipparcos mention no multiplicity. On the other hand
there are the reports of Richard and William...
I will need to revisit this double asap, maybe tonight... |
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| Stuart Clough | ||||
| Star:
Bur 975
Date & Time: 27.07.01. 2135 UT Seeing: 7 <1-10 Seeing Scale (10 best)>. Location of site: Near Halifax West Yorkshire, England. Site classification: Suburban Sky darkness: 4.4 (U Mi) <Limiting magnitude> Temperature: 22 C Conditions: No cloud, Lt. Airs, balmy. Telescope: Orion Optics UK GX250 10" f4.8 Newtonian on Vixen GP mount. Eyepieces: 6 mm Triplane 7.5 mm Plossl, 9mm Ortho, Ultima Barlow. Magnification: x160, x200, x267, x320 |
Certainly the hardest one this session with a published separation of only 1.3 arc seconds. The first evidence of duplicity came at 200 times when I thought I could see elongation and, occasionally, two stars but no real darkness between. The split was confirmed at x267 and almost constant at x320. An impression of yellow in the primary, same colour but deeper in the companion. These colours reported hesitantly. | |||
| Otto Piechowski | ||||
| Star:
Bur 975
Date & Time: 9 PM EDT Saturday, August 18 to 2 AM, Sunday, August 19 Seeing: 8 <1-10 Seeing Scale (10 best)>. Location of site: Lexington, KY, USA Site classification: Urban area Sky darkness: 4.5 (Zenith Unaided) <Limiting magnitude> Conditions: Clear, a bit of haze, still, c. 65 degrees F, very slight breeze Telescope: 150 mm Maksutov Cassegrain (Intes standard MK 67) Eyepieces: 30 mm ?, 16 mm Rini, 11.4 mm Rini, 7 mm and 4 mm celestron orthos, 5 mm University Optics ortho. Magnification: 158x, 360x |
I easily saw the separation,
but I am not sure this star is labeled correctly. The components
are listed as 97/98 yet in Uranometria, the star at that location is
listed as a 6th magnitude star.
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| Jim Jones | ||||
| Star:
Bur 975
Date & Time: 08/26/01 0630 UTC Seeing: 6 <1-10 Seeing Scale (10 best)>. Location of site: Independence, Oregon Site classification: Rural Sky darkness: 5.2 <Limiting magnitude> Conditions: First Quarter + 1 day. Telescope: 8" LX50 Eyepieces: 18mm Radian, 7mm Ortho, 12.5mm CMG, 2x Ultima Magnification: 112x, 160x, 224x, 285x |
After reading the reports
on the 33-doubles page I was pretty much convinced that this is the Bermuda
Triangle of double stars. These four unremarkable stars have been
visited in the past by O. Struve, Burnham, and Hough. Each left a
partial description.
I was disappointed that I
was unable to clearly resolve BU 975. I
This system (if it is a system) consists of four stars that have been reported variously as BU975, STT 367 A-BC (7.3, 10.3 mag, 33.6" at 227d), and HO 648 BC (7.1, 12.7 mag, 21.4" at 074d). I spent a great deal of time over 3 evenings observing this double. I made sure that I had the right system with a single CMG measurement of STT 367 A-BC that yielded a separation of 31.5" and PA 227d. In spite of many attempts under fairly dark skies I was never able to split BU 975. The best I was able to do was an elongation which I considered to be no more than an indication of duplicity. WDS gives the separation of this double as 0.6" measured in 1998. I was also unable to observe
the 12.7 mag companion of HO648.
"The WDS "Neglected Double"
list shows STF 37 AD, STF 37 BC and STF 37 BD as being last reported in
1910. Upon examination it appears that these "neglected" components are
simply "kitty corner" measurements of the the well know and well reported
double-double." Further, as Richard Harshaw reported,
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