Observations made with the Telementor

  Double Stars

The observation of double stars is really a pleasure with this instrument and it's really easy to reach the Telementor's 1.8" theoretical resolution on this type of sky objects. It's really interesting to note that resolution limits are limited quite often not by optics but from "seeing" and thus, our "Refraktor" will surprise more than one observer confident with his/her 6" or 8" aperture telescope. If you get interested in double star observing, please visit the "Spirit of 33 Web Site". Probably, the most active E-Society of double star observers on the whole Internet.
 
 
Observer: Luis Argüelles (Spain)
Star: Regulus, Alpha Leonis
Date and Time: 19, May, 2001. 21:30 UT
Seeing: 8 <1 worst - 10 best> 
Location of Site: Sena de Luna. Leon. Spain 
Site Classification: Rural 
Sky Darkness: 5.5-6.0 <Limiting Magnitude> 
Moon: None
Magnification: 21x, 221x 
Eye Piece(s): 40mm Plössl. 3.8 mm Baader Eudiascopic.
A really easy double even at the reach of a good pair of binoculars. I used Regulus in order to polar-alignment the Zeiss. At 21x, Regulus-A was offering a spectacular view, shining fiercely, while the B component was so far that is a bit difficult to think of this star as a double.

At 221x Regulus-A shows an exquisite difraction pattern. A delight in itself.


 
Observer: Luis Argüelles (Spain)
Star: Epsilon Lyrae
Date and Time: 19, May, 2001. 22:50 UT
Seeing: 8 <1 worst - 10 best> 
Location of Site: Sena de Luna. Leon. Spain 
Site Classification: Rural 
Sky Darkness: 5.5-6.0 <Limiting Magnitude> 
Moon: None
Magnification: 21x, 221x 
Eye Piece(s): 40mm Plössl. 3.8 mm Baader Eudiascopic.
Using Vega as a reference, this beautiful star was a show by itself at 221x and reminded me that we sometimes forget to observe single stars. I think we lose a lot of beauty not observing these cosmic beacons regularly.

The world-famous "double double" was really close, so only a gentle touch to the telescope and Epsilon was inside the FOV. The view of this double represented the 
most espectacular thing on the night. Using only 21x with the Zeiss, I observed a clear elongation on both components!!!. While it's easy to see the split in a Televue Ranger at about 80x and even 50x using a 4" Vixen (Japan) achromat, I needed to rub my eyes to believe what I was observing: A 63 mm (2.5") aperture refractor was rendering elongation at 21x on Epsilon  Lyrae!.

Also, the star located between both "doubles", TYC 3122-1635-1 (RA: 18h 44m 29s, Dec: +39° 38' 23") shining at visual magnitude 10.43, was easily rendered with direct 
vision on the Zeiss, so I'm pretty sure this scope can reach 11.5 visual magnitude without great efforts under dark skies. It's interesting to note that this star is not visible in the 4" Vixen under suburban skies at 3.0 naked-eye limiting magnitude, so one always repeated and almost never learnt lesson: "I don't need more aperture, only better, darker skies and more observing time!".
 


 
Observer: Tom Teague (England)
Star: Beta Lyrae
Date & Time: 2001 August 16 (2100UT)
Seeing: 6 <1-10 Seeing Scale (10 best)>
Location of site: Chester, England
53°11'08"N; 02°51'39"W
Site classification: Suburban
Sky darkness: Not assessed <Limiting magnitude> 
Magnification: x21, x53, x84, x140 and x210
Easily resolved at all powers.  Pale yellow and greenish to my eyes.
Two other nearby comites help to form a pretty arrow-shaped asterism.

Many years ago, I carried out an interesting spectroscopic study of the main component using a Zeiss prismatic pocket spectroscope in conjunction with my 8.5-inch f/5 Newtonian reflector.  I found that the D3 helium line was almost always visible in emission, but the H-alpha line only occasionally.  There did appear to be some correlation with the variability period of the star, which would accord with theory, but the link was a rather weak one.  My investigation only served to confirm what astronomers already knew, which is that the human eye is a hopelessly inadequate detector for serious spectroscopic work!

In common with other members of the group "The Spirit of 33", I could not resist examining the Ring Nebula (M57) while I was in the neighbourhood.  As on many occasions in the past, I found it obvious at all powers from x21, but improving with each increase in magnification up to x140.  This is, as is well known, quite a common effect with planetary nebulae.  Beyond x140, however, there was no further improvement.  I found the best view x84 and x140, at which powers I saw a lovely blue-grey smoke ring.  The central vacuity is not difficult with a/v, but appears smaller (and the surrounding bright annulus correspondingly broader) than in photographs.
 


 
 
Observer: PJ Anway (MI, USA)
Star: Alpha Lyrae
Date & Time: August, 18, 2001  03:00 UT
Seeing: 7 <1-10 Seeing Scale (10 best)>
Transparency:  <0:worst -10:best >
Location of site: Starfest @ Mount Forest, Ontario, Canada
Site classification: Rural
Sky darkness: 5.5 <Limiting magnitude> 
Temperature: 75°F, 24°C
Conditions: No moon, Cloudy with large holes
Telescope: Zeiss Telementor 63mm/840mm refractor on equatorial mount
Eyepieces: Televue 18mm, 12mm radians + 2.4X barlow
Magnification: 47X, 70X, 112X, 168X
Split with averted vision at 47X, seen as parallel to Epsilon Lyrae, no color.

Ambience: Canada's Starfest was an excellent star-party with lousy weather. Rain or solid clouds were the norm for Thursday, Friday, Saturday and Sunday. The only exception was Saturday afternoon  which, though windy, sported regular patches of clear sky in the clouds and Saturday evening which produced a large hole directly overhead for about an hour and a half. With over 900 amateurs starving for some viewing, quite a bit of sun observing was done  on Saturday. I observed with my 100mm for quite a while and tried my hand at imaging through the eyepiece with a hand-held Coolpix 800 digital camera.

The sun was a bit subdued, but I managed to image a few sunspots. I also got a chance to view through both a "Daystar" and a "Coronado AS1-90" H-alpha filters on other people's scopes and was able to see several small flares - a real treat.

Among the many fine talks was one that I believe will  particularly appeal to this group. It was entitled "Double Stars at the Limits of Perception" by Jerry Spevak (a Canadian amateur). 
 


 
 
Observer: Tom Teague (England)
Star: STF 2323 AC
Date & Time: 1,Sept, 2001
Seeing: -- <1-10 Seeing Scale (10 best)>
Location of site: Chester, England
53°11'08"N; 02°51'39"W
Site classification: Suburban
Sky darkness: -- <Limiting magnitude> 
Magnification: 53x, 140x, 210x
I was observing at low power (x53).  After completing the measurements, I decided to examine the star at higher power in order to assess the quality of the seeing.  As soon as I focused the image x140, I spotted a faint and ghostly companion close to the bright A star at a PA of about 340°.  I realised that I had seen the AB pair, without having any advance knowledge of where B was to be found - in fact I had forgotten all about B!  This shows what a marvellous instrument the Telementor is, because there is a brightness difference of about 3 magnitudes between A and B, and they are separated by less than 4".  It was an eerily beautiful sight.  I was also able to see the close companion x210, but not quite as clearly.

 

 
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(c) 2001, Luis Argüelles. Oviedo, Spain