100 doubles

Astroleague Double Star Club observations - the 100 doubles list 


Time: 22:45 - 23:00

Location : Brasov , Romania | Coordinates :  45°40′N 25°37′E

Equipment: Celestron NexStar 6 (150mm / 1500mm) | Eyepieces : 25mm , 10mm - Ploslls + 2,5X barlow

Conditions: The sky is a little "hazzy". Nakedeye magnitude limit is worse than usual (usualy around 3.5-4 for this location). Seeing estimation 6 / 10 on pickering scale.

  • Gamma Andromedae
    60x - clearly separated with small-medium distance at this magnification factor. Big magnitude contrast (3-3.5 mag). Nice colored pair with yellow main star and white-blue secondary
    150x - The colors seems a little bit intense. The blue of the component especially is more obvious than lowest magnitude.
    375x - I estimate the PA to be about 45-50 degrees and the separation seems to take around 1/30 from the current field of view



Time: 22:50 - 23:30 

Location : Brasov , Romania | Coordinates :  45°40′N 25°37′E

Equipment: Celestron NexStar 6 (150mm / 1500mm) | Eyepieces : 25mm , 10mm - Ploslls + 2,5X barlow

Conditions:  Seeing estimation 5 / 10 on pickering scale


  • Eta Cassiopeea 
    60x - The pair is clearly separated with a considerable distance between components even at this low magnification scale. There is a quite big magnitude diffrence between components (probably 3-4 magnitudes). I'm not able to notice any color in the main star neither in secondary star
    150x - The main star still seem white but the secondary star looks a little red-brown color
    375x - I did not notice anything in addition to smaller magnification about the colors.I tryied some rough estimations of separation and PA. The separation is around 1/20 of the field on this magnification.
  •  Delta Cephei
    60x - Very nice colored pair.The main star is yellow-white and the secondary seems little blue. Big separation. Clear magnitude diffrence (2-3 magnitudes probably)
    150x - I'm unable to notice any suplemental things.. The colors are same as previous (did not look more intense as in some cases)
    375x - I tried some rough estimations. I appreciate the separation to be about 1/8 - 1/9 of the current field , and PA in 190-200 range
  • Xi Cephei
    60x - Clearly separated components but quite close at this magnification. Medium magnitude diffrece between components (I estimate about 2-2,5 mag range). I'm unable to notice any color in the components
    150x - Nothing new about colors neither in this magnification factor.
    375x - Also no supplemental information. I estimate the separation to be 1/30 - 1/35 of the current field of view, and the PA in 275 - 290 degrees range.



Time: 0:05 - 1:30 local Time 

Location : Brasov , Romania | Coordinates :  45°40′N 25°37′E 

Equipment: Celestron NexStar 6 (150mm / 1500mm) | Eyepieces : 25mm , 10mm - Ploslls + 2,5X barlow

Conditions:  Seeing estimation 4 / 10 on pickering scale ,Very clean sky with amazing transparecy for this inner city location. Unfortunately the seeing is not so fine.

  • Alpha Ursae Minoris (Polaris)
    60x - Huge magnitude diffrence (5-6 magnitudes), but also quite high separation. Probably if separation were a little smaller this could make the secondary quite a challange in such a high diffrece pair. Also now I had the impresion for a couple of times that I can't see the component because is to faint. I can't notice any colors neither in secondary or main star. Both seems to be white stars.
    150x - No diffreces. The main star seems clearly white color.
    375x - I'm not able to estimate the PA using my method (stoping the mount gears and let the pair drift and evaluate the angle between them). The star is not moving even with gears stopped (which is normal because is located very close to celestial north pole). I estimate the separation to be 1/12 of the current field.
    General impresion : Intresting especialy because of the high magnitude contrast.
  • Iota Trianguli
    60x - At the first sight there seemed to be no component at this magnification. Looking again I was able to see that there is a double star but the separation was not very clear. Just for short periods I had the impression that I can see blank space between components. Also because of this I can hardly evaluate the magnitude diffrence between components. I think there is some diffrence but is hard to quantify how much.
    150x - Even at this magnification the pair is still close. Still , in this case the components are clearly separated. Beeing able now to distinguish the components I can evaluate the magnitude diffrence which I thik is around 2-3 magnitudes. The main star looks a little yellow (maybe more precisely white-yellow). The secondary seems blue.
    375x - Now the distance is quite confortable. Still the bad seeing bothers me a little in evaluations (mostly because the pair is more close than the last one). I evaluate that the PA is around 60-70 degrees and the separation is around 1/40 of the field 
    General impresion: Very nice pair. It seemed to be more atractive because the small separation which makes it a little more challenging object.
  • Eta Persei
    60x - Quite big separation. Also pretty big magitude contrast (I think is between 3 and 4 magnitudes). The main star look a litte yellowish.
    150x - Now the yellow of the main star looks more obvious. I'm not sure about the secondary but it seems to be blue.
    375x - No supplemental information. I tried to estimate the parameters. The PA I think is in the 290-300 degrees range. The separation seem to be about 1/9 - 1/10 of the current field.

  • Gamma Arietis
    60x - Pretty close pair but still clearly separated (I can clearly see the black sky between components). The components seem equal magnitude, quite bright, and both are white-blue in color.
    150x - I can't notice any magnitude diffrence. There seems to be sometime a small color diffrence but I'm not sure about it (just had this impresion for a few times)
    375x - I evaluate the separation to be around 1/18 - 1/20 of the field. The pair looks paralel with the North-South axe but looking again it seemed there is some small angle. So I estimate there is about 5-10 degrees angle ( PA 350-355 degrees )
    General impresion : A very nice view. Pretty bright equal close pair with same color in both components.