Zeta Cancri 

Tim Leese
Star: Zeta Cancri  
Date and Time: 4th March 2001 (21:00 UT)  
Seeing: 6/7 <1 worst - 10 best>   
Location of Site: Cheshire. UK  
53° 15' N -2º 33' W  
Site Classification: Suburban   
Sky Darkness: 3 <Limiting Magnitude>  
Conditions: Very cold and crisp. Moon just past 1st quarter.  
Telescope: 200mm f/6  Newtonian mounted over a Vixen GP mount (manual slow motion).  
Any Quoted PA or SEP using Celestron micro guide (CMG)  
Magnification: X67, X134, X224,X480, X800  		 Using X67 (ortho) I observed this double star for the first time.  

A/B seemed to be an off white to pale yellow and C pale yellow also.  
Using a barlow lens with an 18mm ortho I increased the magnification to X134 where I suspected some elongation for A/B. Increasing the magnification to X224 I observed a definite peanut shaped star (more of a dumb bell shape really ) for A/B. Changing the eyepiece to a 5mm Lanthanum  I could see three stars quickly drift across the FOV.  
  
The image was somewhat fuzzy but I could definitely see three stars.  
Observing the drift across the field the B component appeared to be slightly  
N of the W- E  line ( approx.80- 85deg ) The C component appeared to be a bit more N again(70-80deg).  

After watching the stars ( bubbling and boiling as they were) whiz across the field I realised I still had my X3.35 barlow in the drawtube, so with this scope and eyepiece, it meant I was using X800 magnification.  
  
Dropping down to X480 I  observed the three stars once more ( just ) at the same PA.  
 

 
Tom Teague
Star: Zeta Cancri 
Date & Time: 2001 March 5 (2215 UT) 
Seeing: 5 <1-10 Seeing Scale (10 best)>.  
Location of site: Chester, England 
(53 11 08N; 02 51 39W)  
Site classification: Suburban   
Sky darkness: 3 (Moon high and bright) <Limiting magnitude>  
Telescope: 63/840mm Zeiss Telementor refractor  
Magnification: x56, x140, x210		 Split cleanly x56.  x210 is far too high a power for the seeing tonight, and even x140 is on the high side.  Comes (C) follows brighter primary.  Component A is white, and C is a dull, indeterminate hue.  B not seen (below resolving ability of telescope).  Poor colours. 
 

 
Ilario Melandri
Star: Zeta Cancri 
Date & Time: 19 Mar 2001
Seeing: 6 <1-10 Seeing Scale (10 best)>   
Location of site: S.Romualdo, Ravenna, Italy
Site classification: Rural  
Sky darkness: 4.5 <Telescope Limiting magnitude>
Temperature: +11ºC
Telescope: 150mm f/15 achromatic refractor
(lens by Romano Zen, Venice)
Eyepiece(s): Clave Plossl 16 mm)
Magnification: 140 x 
   		 Note: I have waited for a better seeing during he observing session, but nothing to do about, the tightest couple is un-splittable
 
     
 
 
 
William L. Schart
Star: Zeta Cancri 
Date & Time: 3/4/01 8:08 pm CST 
Seeing: 7 <1-10 Seeing Scale (10 best)>   
Location of site: Killeen, TX (Lat 31 N, Elev 600 ft)   
Site classification: Suburban   
Sky darkness: 4 <Limiting magnitude>   
Moon:  1/4 
Telescope: Celestar 8" SCT    
Magnification: 78x, 120x, 203x, 170x (MG)		 A pair of pastel yellow orange headlights. I got the separation at 6" and the PA at 71d. I had a great deal of trouble with this measurement until I realized "SCT, idiot!" I had forgeten the new orientation. I still came up about 10 d from the figure in the list and wasn¹t able to figure out why. At the mid power, I thought that I could make 
out a bump on the primary in about the right PA to be the tight B star, but I wouldn¹t swear to it. 
  
Ambience: No animal companions, neighbor lights, music, artillery, etc. In fact, not much ambience except for the joy of probing some of the wonders of these multiple systems 
 

 

 
Bob Hogeveen
Star: Zeta Cancri  
Date & Time: 06 mar 2001, 20.00 - 23.00 
Seeing: 4 (?) <1-10 Seeing Scale (10 best)>    
Location of site: Annen, The Netherlands 
53ºN 6ºE 
Site classification: Between Suburban and rural    
Sky darkness: 4 (away from Moon) <Limiting magnitude> 
Transparency: ? <1 worst - 10 best> 
Temperature: 1º C 
Conditions: Stiff breeze from E, thin clouds passing, almost full moon in Cancer 
Telescope: 11" f/10 Celestron SCT on Losmandy G-11 
80mm f/6 Guan Sheng on C11 
Magnification: from 12x to 400x 
Eyepiece(s): TV Plossl 40mm, 20mm, Meade Plossl 25mm, Bresser Plossl 10mm, Vixen LV 7mm. 		 A difficult, on-the-edge split of AB with C11 at 280x and 400x. The stars were rather fuzzy and jumping around a bit in the FOV. Most of the time AB were elongated but not split. Only for a few moments I had a hint of darkness between the stars. 
  
The yellowish color of this pair adds to the peanut-impression as Tim Leese descripes. Using the GS80 C is nicely separated from AB with 24x.  
  
This is a very beautiful and interesting pair which has to be revisited under better conditions. Rating 2 for the moment.

 

 

 
Eddy O'connor
Star: Zeta Cancri  
Date & Time: 9.30 -11p.m local; UT +11 
Thursday, March 15th 2001. 
Seeing: 8 <1-10 Seeing Scale (10 best)>  
Transparency: 6/10 
Location of site: Terara, New South  
Wales, Australia 
150º.38E, 34º.52S 
Site classification: Suburban  
Sky darkness: 5-5.5 <Limiting magnitude>    
Temperature: 17ºC, Calm. No Moon 
Telescope: 8" Newt. F9 
Eyepieces: 25mm K, 12.5 mm ortho   
Magnification:  
Harshaw Scale: 3 (1-5. 1 best). 		 This mag.5.6 star stands out in a dark field in the finder, making it easy to locate. The triple only resolved into two stars for me and resolution at high power was impossible tonight. 
 
Comments: I saw a Whitish Blue primary and a Rose coloured companion with a faint star wide on the western border. Pleasant field. (HS 3). 

 
Philippe Dejocas
Star: Zeta Cancri  
Date & Time: March 19, 2001 
Seeing: 5.5 <1-10 Seeing Scale (10 best)>    
Location of site: Ottawa/Hull, Canada 
Site classification: suburban - urban    
Sky darkness: ~ 11.8  <Telescope Limiting magnitude> 
Transparency (vis.): ~ 4.6 
Temperature: 3°C/ -4°C (beg/end)  
Winds : light W/SW 
Humidity : around 50% 
Sky : Dark blue/grey with a slight hint of haze, odd thin high altitude clouds. 
Telescope:  6" f5 Newtonian "Aldebaran" 
Magnification: 85x, 120x 
 
Star: Zeta Cancri   
Date & Time:  April 4 and 5 2001 
Seeing: 7.5 <1-10 Seeing Scale (10 best)>.  
Location of site: Ottawa/Hull, Canada  
Site classification: suburban, urban 
Sky darkness: ~ 4.3- UMi <Limiting magnitude>  
Temperature: 8°C/ 2°C (beg/end) 
Humidity : below 50% 
Sky : Dark blue, even with the presence of 
the moon on both nights. 
Telescope: Aldebaran 6" f5 Newtonian 
Magnification: 120x, 225x 		 I did not attempt the AB components, but AB-C was resolved with 85x, and showed itself better at 120x . I did not try to get a sense of any colors as by that time I was getting tired and wanted to spend some time trying to catch comet McNaught-Hartley at least once. 
  
 
 
 
 
 
 
 
 
 
 
 
At 120x showed a nice clear gap between AB and C, and at 225x I finally got a separation between A and B. AB were a nice pale yellow (Daffodil) with the C cpn coming across as light blue grey. 
 
 
 
 
 

 

 
Glen Chapman
Star: Zeta Cancri  
Date & Time: 17/3/01 
Seeing: 8.5 to 9.5 <1-10 Seeing Scale (10 best)>    
Location of site: Seven Hills, NSW, Australia 
Site classification: Semi Urban    
Sky darkness: 4.3 <Limiting magnitude> 
Sky condition: No Moon, No clouds, slight breeze 
Temperature: 24ºC 
Telescope: 203mm F6 Dobsonian 
Magnification: 50X, 75X, 320X 		 Description:  A & C split at 75. A - pale yellow, C solid blue 
Notes: Although B was unsighted the A C combination was very similar to Iota Cancri. Would highly recommend. Noted faintest of elongation at 320X. 
Not willing to claim due to high mag in use. 
  
Ambience: In the distance I could hear the faint singing of happy birthday. I competed 
with my radio switched to a provincial rugby match. The night is unbelievable still and dark. A faint very fast moving meteor splits the heart of Cancer. 
 
Although not in order, the following deep sky objects where observed during the night. M67. A fascinating open cluster, seemed to weep from the sky, a near extinguished firework. Some fifty stars could be identified, with strong frosting through the rest of the cluster hinting at greater treasures. M44 - a reason I don’t normally chase clusters. Merger and sparse, It appears as no more than a poor relation to the sparkling M45, now racing to the western horizon taking the promise of forgotten summers with it. 
 
I answered the call of my southern kin. NGC 5139 Omega Cent, filled my eyepiece, its fat and gloating carapace of stars a welcome friend. NGC 5128. The hamburger galaxy was next. Finally I felt the need to attend to the keyhole nebula and its attending suicidal Eta Carina - her tell tale orange peanut beaconing of hidden titanic struggles of nature. 

 
John Ryan
Star: Zeta Cancri  
Date & Time: 03/31/01  23:00 UT 
Seeing: 5 (variable) <1-10 Seeing Scale (10 best)>    
Location of site: Barraras, Salamanca, Spain   
Site classification: Suburban and Rural    
Sky darkness: 4.0 <Telescope Limiting magnitude> 
Temperature: 6ºC  
Telescope: Meade 8 inch SCT 
Magnification: 25 ultrascopic (80X), 
12mm plossel (167X), 7mm ortho (285X), 
6mm ortho (333X) and a 4mm ortho (500X) 		 Same comments about the moon and the seeing. This double was the jewel of the night. When I found it with the 25mm I could see the split between the A and C components. 
  
With the 12mm the split was better and you could see that the A component was swollen with the B component. The combination of the two were brighter and there was a slight elongation. With the 7mm and then the 6mm orthos the elongation was more pronounced but still no split. 
  
The 8" Sct is capable of splitting this under good conditions but not tonight with the seeing so marginal. The surprise of the nite was when I inserted the 4mm ortho at 500X I got a double airy disc and rings of the AB combination and the airy disk and rings of the C component. I could still not split the AB components but it was nice to see the comparison between the  AB and the C airy disk combinations. I stayed with this for about 20 min. hoping for a quiet spell but no luck. 
   
Tonight was the first nite that I tried out the new 4mm and 6mm orthos that I bought from Orion UK this winter. I was very pleased with them and I now have a set or four orthos of 4mm, 5mm, 6mm and 7mm. Thanks to Tom Teague for tipping me off about the orthos and also for his always persuasive argument that with double stars there is no limit to the magnification which I found out with the 4mm at 500X with Zeta. I have to return to this double on a better nite to see if I can split AB with the 8". 
    
Rating of a 4 because of the AB combination compared to C. All components white. Very nice.  
  
Ambience: These observing nites were cool with very little wind with temperatures about 12º to 14ºC at nitefall and falling to about 6ºC at 1:00AM. There is a small pond about 200 meters to the south full of small frogs and these were raising a tremendous racket. My wife ventured that it must be the mating season for the frogs. Also the nite was full of the cattle and sheep sounds from the various corrals around the village. Many of the sheep and cattle have bells attached to their necks and it sounded like a small concert of bells. Finally the multitude of sheep dogs and the others added to the sounds of the nite. The sounds of all these animals were somewhat muted by the distance and the trees so that it was more sonorous and friendly than a bother. 
  
After such a long dryspell it was great getting out for the two nites. I felt like a drug addict finally getting his fix. That might be an extreme example but once the addiction of astronomy gets in your blood it is hard to go for long spells without observing. 

 
Jim Jones
Star: Zeta Cancri  
Date and Time: 4/15/01  04:36 UTC 
Seeing: 7 <1 worst - 10 best>  
Location of Site: Lake Oswego, Oregon 
Site Classification: Suburban  
Sky Darkness: 3.5 <Limiting Magnitude> 
Telescope: 8 inch LX50 SCT 
Magnification: 112x, 285x, 570x 
Eye Piece(s): 18mm Radian, 7mm UO Ortho, 2x Ultima Barlow 		 Est PA AB-C.....090d   (no instrumentation) 
AB..... Not quite in line with  AB-C 
Observed Color   AB..... yellow 
                 C.......Yellow 

AB listed in WDS as 0.7" separation  measured in 1998.  AB-C was a clean split at 112x.  AB was an elongation at 285x and a definite split at 570x.  It was very quiet.  At 570x I was aware of the quiet thrum-thrum of the RA motor and the sound of my own pulse pounding in my ears.  Each time the motor thrummed the image would give a tiny bounce.  Very strange ambiance. 

 
Thad Robosson
Star: Zeta Cancri  
Date and Time: 17th, April, 2001
Seeing: 7 <1 worst - 10 best>
Transparency: 4 <1 worst - 10 best>
(pretty crappy transparency for this site)
Location of Site: Flat Iron site, Arizona
33º 39928 N 112º 49152 W
Site Classification: Rural
Sky Darkness:  <Limiting Magnitude> 
Telescope: 8"f/6 reflector on EQ mount.
Magnification: 
Eye Piece(s): 10 & 15 mm Vixen Lanthanum, 
2x shorty barlow, 5x Televue barlow.		 Fairly yellow at lower powers, ABxC was easy  (80x)  Bumping up to 120x elongated AB just a smidgen. 240x washed out most of the color, and AB was definately elongated, but not quite split. 400x finally produced the desired results, a clean split nearly 60% of the time.
 
I drew this system for comparison with past and future observations, as the B comp. will be swinging past the C comp. in 2002.  In comparing with last year's observation, It is easy to see that it has moved, and the split last year occured at very nearly the same power.
 
I estimate  the PA of AB to be about 75 and 70 for ABxC. ( No instruments were used to determine PA )

 
Otto Piechowski
Star: Zeta Cancri
Date and Time: April 18, 2001,
10 PM EDST
Seeing: 7 <1 worst - 10 best>
Location of Site: Lexington, Kentucky
(within city: about 1/3 million souls)
Site Classification: Urban
Sky Darkness:  <Limiting Magnitude> 
Telescope: 150 mm maksutov cassegrain 
(MK 67 standard) 
Magnification: 257x, 360x and 450x
Eye Piece(s): 7 mm ortho,  5 mm UO ortho, 4 mm ortho)		 The A and B components were clearly separated with the use of 7mm eyepiece, 
giving an effective magnification of 257X. A clear black line/space was seen
between the airy disks of the A and B component.

The separation was also seen at higher magnifications (360X and 450X) but the
feeling was that the separation was perceived most clearly at 257X.

A particularly fine CCD image of this system can be found at:
http://www.cfht.hawaii.edu/Science/Astros/Imageofweek/ciw010500.html
This was provided me by Jeff Barbour in California, USA.
I think, when resolved, that zeta cancri is very beautiful.
 

 
Thad Robosson
Star: Zeta Cancri
Date & Time: 1:30 to 3:30 UT, 4/24 (UT) 
Seeing: 6~7 <1-10 Seeing Scale (10 best)>
Transparency: About 3~3.5/10 
Location of site: Phoenix, USA
33º 32.674N, -112º 08.029W
Site classification: n
Sky darkness: -- <Limiting magnitude>
Weather: Clear, warm, very slight breeze.
Temperature: 
Telescope:  8" f/6 newtonian on Eq mount
with wonderfully large setting circles
Eyepieces: Vixen Lanthanum 10 and 15mm,
Meade 32 mm Super wide, Celestron 2x barlow,
Teleview  5x powermate.
Magnification: 38x, 120x, 400x		 A favorite!  ABxC seen in tight proximity at 38x. 120x proved ABxC easily separated with AB slightly elongated.  15mm w/5x barlow (400x) proves to be the lowest power yet in which I have been able to split this one.

AB is a definated figure 8 most of the time with occasions of dark lane between.  I est the PA at 85* for AB and 80* for ABxC.  Rated a 2. It is obvious from previous sketches that this system is quite dynamic, with the B comp. catching up and ready to lap the C comp. Compared with drawings from last year, it has obviously moved some.
 

 
Mary Flanagan
Star: Zeta Cancri
Date & Time: 27 Apr 2001 03:15 UT;
26 Apr. 10:15 CDT
Seeing: 7 <1-10 Seeing Scale (10 best)>
Transparency: 7 <1-10 Scale (10 best)>
Location of site: Apple Valley MN, USA
93º 14' 25" W; 44º 45' 17"N
Site classification: Suburban 
Sky darkness: 4 <Limiting magnitude> 
Telescope: 12.5" f/5 Dobsonian 
Magnification: 106x, 144x		 Wide figure 8 at 106x; came apart at 144x. Could split only the pale yellowish pair; no other components seen.