Gamma Delphinus 

Richard Harshaw
Star: Gamma Delphinus (STF 2727) 
Location of site: Northern Kansas City, Missouri (USA) 
94d 30m west longitude, 39d 15m north latitude 
980 ft above Mean Sea Level 
Date of observations (UT): UT: 02:15 of Sept. 16, 2000 
Site classification: suburban 
Sky conditions
seeing-- 4/10 up to 8/10, in short spans of time 
transparency-- 8 out of 10 
limiting visual magnitude-- 5.0 mag 
Telescope: Celestron C-8 
Eyepiece: 20mm  (104x) 
 
 
Position:  2047+1607 
Magnitudes:  4.27, 5.15 
Sep/PA's:  9.5 - / 267 -. 
Year of last measurement:  1995 
Distance (light years):  101 
Luminosity (in suns):  23 
Eyepiece and magnification:  20mm  (104x). 
Colors noted:  Y!! and pB.  Webb saw D and bG or Y and pG.  Franks saw Y! and gB. 
Very, very nice pair! 
A premature orbit has been computed. 
1823, 11.9" @ 274. 
There is also a faint pair (8m, 9m, about 12" separation) some 15' south. 
Rating:  1.5.  Probably the prettiest pair on the entire Olympic List. 
 
 
 
 
William L. Schart
Star: Gamma Delphinus (STF 2727) 
Date & Time: 9/16/00 8:54 pm CDT 
Seeing: 8 <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>  
Telescope: Orion 6" Dob.  
Magnification: 32x, 98x 
 
This constellation aappears to me to be a tadpole, and this pair is the tadpole's nose. Tight, but I definately split it at 32x. Both members appeared white to yellow-white to me. Separation 8", PA 269. 
 
 
 
Jim Jones
Star: Gamma Delphinus (STF 2727) 
Date & Time: 0630 UTC, Sept 17, 2000 
Seeing: 8 <1-10 Seeing Scale (10 best)> 
Location of site: Lake Oswego, Oregon, USA  
Site classification: Suburban 
Sky darkness: 3.8 <Limiting magnitude>  
Telescope: 8 inch LX50 SCT 
Eye Piece(s): 42 mm Ultima  
Magnification: 47x 
  
 
Est PA without instrumentation...280d. 
Very nice double with primary only slightly brighter than companion. Both appear yellow but may be seeing effects of very bright moon. 
 
While I was documenting this pair a jet plane passed above the moon leaving a luminous con trail accross the sky.  It only persisted for less than a minute and then it was gone. 
 

 

 
 

 
 
Eddy O'Connor
Star: Gamma Delphinus (STF 2727) 
Date & Time: 8 -10 p.m local; UT +11. Monday, September 18th 2000 
Seeing: 5-6 <1-10 Seeing Scale (10 best)> 
Transparency: 9. No Moon. Temp 18º C. Windy. 
Location of Site: Terara, New South Wales, Australia, Long.150.38 degrees; 
South 34.52. 
Site Classification: Suburban 
Sky darkness: 4.5 <Limiting magnitude> 
Instrument: 8"  F9 Dobsonian 
Magnification: 72X (25mm Kellner)
This double double is so popular that little remains to add to the list of superlatives. Located on the top of this kite-like asterism  different observers record different colours. I have read the following(Primary first) Yellow/Green; Golden/Pale yellow;Yellow/Emerald. 

Comments: I recorded on this occasion: a Deep yellow primary with an easy split at low power and the secondary an Ashen Blue. The PA is 268 and the separation is a comfortable 9.6".The Observer's Guide  states that this true binary is 100 Light Years distant and the luminosities are 16 and 8 times that of our Sun respectively. The close fainter double of Struve 2725 appears in the same field making this group an outstanding  mascot in the Sailing Events. 
 

 
 
Patrick J. Anway 
Star: Gamma Delphinus (STF 2727) 
Date & Time: Sept. 17, 2000, 11pm EDT (0300 UT) 
Seeing: 7 <1-10 Seeing Scale (10 best)> 
Location of Site: Munising Michigan USA 
Site Classification: Rural 
Sky darkness: 5.5 (in the holes) <limiting magnitude> 
Sky condition: high clouds, moon rising 
Temperature: 42º F (5º C) 
Telescope: Zeiss 63mm/840mm f/13.3 
Eyepieces: 7mm, 10mm, 16mm, 18mm orthos 

 
 

Using 10mm for 84X, the star separated into a most lovely pair of a yellow primary and blue secondary. This comes close to what Olcott saw, though he adds green to the bluish secondary. Smyth however drops the blue and gives "light emerald" for the companion. Paul Couteau agrees, giving "orange and green" for the components. Discovered by Struve in 1830, the distance is estimated at 100 light years. In the same field is another Struve double - STF 2725. 
 
 

 
 
 
 

 
 
Tim Leese
Star: Gamma Delphinus (STF 2727) 
Date & Time 
Seeing: 6-7 <1-10 Seeing Scale (10 best)>  
Location of site: Cheshire. UK 
53° 15' N –2º 33' W  
Site classification: Suburban  
Sky darkness: 3.5 <Limiting magnitude>  
Telescope: 200mm f/6  Newtonian scope  mounted over a Vixen GP mount (manual slow motion). 
Any Quoted PA or SEP using micro guide. 
Magnification: X60, X120 

 

I have read that this star is a "showpiece double" and once I had located this system I would certainly agree. Using a magnification of X120 a yellow/white primary could be observed with a pale blue secondary at an estimated PA of 270deg( W-E line ) in the eyepiece FOV. A very pleasing view was obtained using a magnification of X60 where the colours of the two components seemed more prominent. An outstanding view, this double, one to return to again and again. 
 
 

 
 

 
 

 
 
Ilario Melandri
Star: Gamma Delphinus (STF 2727) 
Date & Time: 21/9/2000 – 20.00 UT 
Seeing: 4 <1-10 Seeing Scale (10 best)>  
Location of site: Italy, Ravenna, San Romualdo, Lat 44 32’N Lon 12 08’E 
Elevation: 0 m 
Site classification: Rural  
Sky darkness: 5 <Limiting magnitude> 
Temperature: +14C 
Telescope: 150 mm f/15 achromatic refractor (lens by Romano Zen, Venice). 
Magnification: 140x (Plossl 16mm) 
Sep. 9.6”, distance 75 light years. 
 
The distance between the two components corresponds at about 221 Astronomical Units, almost 3 times the diameter of Pluto’s orbit around 
the Sun. 
 
 
 
 
 
Tom Teague
Star: Gamma Delphinus (STF 2727) 
Date & Time: 2000 September 23 (2030 UT) 
Seeing: 7 <1-10 Seeing Scale (10 best)>. 
Location of site: Chester, England (53 11 08N; 02 51 39W) 
Site classification: Suburban  
Sky darkness: 3 (thin high cloud) <Limiting magnitude> 
Telescope: 63mm Zeiss Telementor refractor 
Magnification: x53, x84, x140, x210 
  
 
At lower powers, I saw this fine pair as yellow and white, or (more poetically) as gold and silver.  Rather surprisingly, I found that the highest power (x210) gave the best view.  At this power, I noted a lovely, subtle colour contrast, which I would describe as pale yellow and greenish white.  Estimated PA = 270. 
 
The ambience was interesting tonight.  No wildlife, but a freshening breeze, giving premonitions of equinoctial gales to come.  Towards 2100 UT, the cloud thickened, and further observing became impossible.  Someone is holding a noisy and impressive firework party over in the west, and the house is illuminated by frequent brilliant flashes of light. 
 

 

 
 
Mary Flanagan
Star: Gamma Delphinus (STF 2727) 
Date & Time: 26 Sep 2000 03:48; CDT 25 Sep 22:48 
Seeing: From 4 to 7 <1-10 Seeing Scale (10 best)> 
Transparency: around 8  (1-10)  
Location of site: Apple Valley MN, USA 
 93d 14m 25s W; 44d 45m 17s N 
Site classification: Suburban   
Sky darkness: ~4 <Limiting magnitude>  
Telescope: 8" f/6 Dobsonian 
Magnification: 80x (15mm TV Plossl) 
 
 
This one's another old friend; a pretty, easy pair at 80x; primary orange 
gold, secondary pale blue.  At other times, I've seen both as pale orange. 
Strange how this can vary from one night to the next. 

Olympic commentary:  Another easy tumbling run . . . 

 

 

 
 
Pino Bandini
Star: Gamma Delphinus (STF 2727) 
Location of site: Ravenna, Italy 
Date of observations (UT): 30/9/2000
22.04 UT
Site classification: Urban 
Sky conditions
Seeing: 6 (10 best) 
Temperature: +19C
Limiting visual magnitude: -- 
Telescope: Celestron 8
Magnification: 200x (Plossl 10mm)
 
 
Note: color white of both components