Sigma Orionis 

William L. Schart
Star: Sigma Orionis 
Date & Time:  November, 26th, 1998 - 10:25 pm CST 
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, 48x, 120x 
 

Star: Sigma Orionis 
Date & Time:  12/26/99 10:29 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: 4.5 <Limiting magnitude> 
Telescope: Orion 6" Dob. 
Magnification: 32x, 48x, 72x, 98x, 144x 
 

Star: Sigma Orionis 
Date & Time:  1/17/00 7:44 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: 3 <Limiting magnitude>,  Moon near full and near object 
Telescope: Orion 6" Dob with modified Quickcam 
Magnification: ---
 

 (Double exposure in order to obtain Separation & PA)
 

 Located a short distance from zeta Ori. Not visible to me naked-eye, but clearly visible in the same finder field. A 4 star system, with a bright primary, 
somewhat fainter second member, and 2 very faint stars. At low power it is apparent that this is a multiple, and the 3 brightest are split at 48x. It took 120x to 
split  the fourth member. No color, other than white, noticable for any of them. 
 

Appears in the same field of view as Struve 761. Easily split at 32x, but 72X reveals a third member very close to the primary. The primary is yellow, with blueish companions. The closest pair are 17" apart, the 2 fainter ones are 25" apart, the whole group spans 33". PA's: from the primary to the closest secondary: 90 degrees, from this secondary to the farthest one is 120 degrees, while from the primary to the farthest member 110 degrees. 
 
 

This evening I proceeded to analyze the other images I acquired Monday. First of all was sigma. I was somewhat pleasantly surprised to notice a somewhat faint but positive image of Struve 761 on one of the pictures. 

Unfortunately, this pair had drifted out of the field of view on the second image, which prevented me from measuring the PA of this pair. However, I was able to determine the separation, as well as both measurements for sigma. 

Data: separation: 41.6", PA 241d 1' 

 

 
Craig M. Carver
Star: Sigma Orionis 
Date & Time:  11/27/98  0100 LT 
Seeing:  5 <1-10 Seeing Scale (10 best)> 
Location of site:  Randalman, NC  (Lat 36.07, Long 79.79, Elev. 500 ft) 
Site classification: Rural 
Sky darkness:  5.1-5.3  <Limiting magnitude> 
Telescope: 6" Maksutov 
Magnification: 95x, 190x 		 A very nice foursome of varying shades of blue.  One of my favorites.  The primary is white, but the B and C stars, the next brightest pair are blue, the mag 7.5 
B star being specially blue.  B and D are almost at the same angle. 

 
Penny Fisher
Star: Sigma Orionis
Date & Time:  12/11/98 
Seeing:  6 <1-10 Seeing Scale (10 best)> 
Location of site:  Englishtown NJ, 40.25  N  74.333 W 
Site classification: Suburban 
Sky darkness:  4  <Limiting magnitude> 
Telescope: 8 inch Dob 
Magnification: 47x 
 
 
Star: Sigma Orionis
Date & Time:  12/25/99, 19:45 EST 
Seeing:  6 <1-10 Seeing Scale (10 best)> 
Location of site:  Englishtown NJ, 40.25  N  74.333 W 
Site classification: Suburban 
Sky darkness:  4  <Limiting magnitude> 
Telescope: 8 inch Dob 
Magnification: 96x		 Was able to find this multiple quite easily, and split easily at least four components.  The two brighter ones were a medium blue. The two other components (possibly C and D) were both a deeper blue, bordering on a blue violet or reddish blue coloration.  This was a very pretty system! 
 
 
 
 
 
 
 
 

Easily found this multiple again near Zeti Ori. 

This system was striking in that all components are a hue of blue or blue-white. I also noticed some lavendar coloration in the dimmer secondary stars.   I wonder if all Orion's doubles have some sort of blueish coloration, and if this is because much of the constellation is comprised of young, and hot stars?? As I ruminate on this, I make my sights to the next Orion double... 
 

 

 
Chuck Layton
Star: Sigma Orionis 
Date of Observation:  Jan. 11, 1999 
Time of Observation:  0445 UT 
Seeing (1 - 10, 10 best):  5 
Site classification: Suburban 
Limiting Mag. (naked eye):  4.8 
Instrument Used: 20cm f/6 Eq. Newtonian 
Magnifications Used: 122X 		 Observed Colorations of Components:  A and D are white while B and C are blueish white. 
Other comments:  Very interesting and pleasing arrangement with 4 contrasting magnitudes. 

 
Paolo Morini
Star: Sigma Orionis 
Date & Time: 25/01/1999, 22:30 UTC 
Seeing:  7 <1-10 Seeing Scale (10 best)> 
Location of site: At my home in Ravenna – Italy. 
Site classification: Urban 
Sky darkness: 3.5-4  <Limiting magnitude> (haze and 1st quarter moon) 
Telescope: TeleVue Pronto 70mm f480mm 
Magnification: 77x-146x (TV 20 and 10.5 eyepiece with Barlow lens and star diagonal) 
 
 
Star: Sigma Orionis 
Date & Time: 25/01/1999 
Seeing:  5 <1-10 Seeing Scale (10 best)> 
Location of site: At my home in Ravenna – Italy. 
Site classification: Urban 
Sky darkness: 5  <Limiting magnitude> (haze and 1st quarter moon) 
Telescope: Takahashi FS102 
Magnification: 164x (Takahashi LE 5)		 Observed the component of mag 4-7.5-6.5, but the component of mag 10 was not visible. Near was Struve 761 but I have to return later as it seems a triple rather than a double system. No coloration observed. 
 
 
 
 
 
 
 
 

Seen all the four components. 
 

 

 
Dave Mitsky
Star: Sigma Orionis 
Date & Time: 1/27/99 07:08 UT 
Seeing: 6 <1-10 Seeing Scale (10 best)>
Transparency: ~ 6 
Location of site: ASH Naylor Observatory (http://www.msd.org/obs.htm) 
near Lewisberry, PA 
Site classification: Rural 
Sky darkness: < 5.0 <Limiting magnitude> moonlight 
Telescope: 17" f/15 classical Cassegrain 
Magnification: 118x, 202x, 259x 		 Orion was well on its way to setting when I observed the great quintuple star system Sigma Orionis, which is located to the south of Zeta and close to the famous Horsehead Nebula (B33).  Only 4 of the stars (magnitudes 4, 6.5, 7.5, and 10) can be seen optically no matter what aperture is used since the fifth component is spectroscopic. There is variation in color from white to blue-white to an indeterminate shade. 
 

 
Orlon Petterson, Marilyn Head, Giles Reid and David Downing
Star: Sigma Orionis 
Date & Time: 13/02/99, 10:00UT to 14:00 UT 
Seeing: 7-8 got better as night progressed 
Location:  Staveley, ~80km SW of Christchurch, New Zealand. 
Instrument: 102mm f/9.8 refractor 
Sky darkness: 6 - 6.5  <Limiting magnitude> Again didn't actually make a definitive measure but the sky was dark and the transparency really good. 
Magnification: 50x 		 This multiple system I was able to identify 3 of the 4 stars at 50x, at higher magnification I was unable to locate the 4th star.  At 10 mag the conditions may not have allowed it to be seen. 
 

 
Ilario Melandri
Star: Sigma Orionis 
Date & Time: 6/Dec/1999 – 19.16 UTC  
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: 5.5  <Limiting magnitude>
Temperature: -0.5C 
Telescope: 150 mm f/15 achromatic refractor 
Magnification: 140 x (eyepiece Plossl Clavé 16 mm)

 

 
Tomás Vazquez
Star: Sigma Orionis 
Date & Time:  December, 15, 1999 23:29:42,  23:29:58..UT 
Seeing:  4 <1-10 Seeing Scale (10 best)> 
Location of site: 37 24 N. 5 58 W. Sevilla, Spain 
Site classification: Urban 
Sky darkness: 3  <Limiting magnitude> 
Telescope: Celestron C8” D:203mm. f/6,3 
Magnification: CCD Camera 

 		 Observing Method: CCD ST-4 Camera 
Integration time: 5 seconds 
Software used (reading/treatment): Lucas 1.1 / Laia 3.1g 
Image Position: North up, East left 

In the image we can observe the main component, a blue giant, shining at magnitude 2.1-2.3 and the secondary, (also a blue star) of 6.3 magnitude located north from the main component. 

These stars are located 820 light years from us. Thir spectral class are O9-B0 and it’s an Algol type variable. 
 

 
Randall Heckman
Star: Sigma Orionis 
Date & Time: 12/30/99 at 3:30 UT 
Seeing: 6 
Location of Site: Heckman Observatory 
40 37' 10" N and 99 03' 50" W 
Site Classification:  Rural 
Sky Darkness (Limiting Magnitude): 4 
Telescope:  8" Orion Dob 
Magnification: 120x 		 Separation (Clear or Toughing): Clear 
Magnitude Comment: The mag 10.3 component seems to be exceptionally dim. 
Color Comment: Colorless 
General Comment: Nice quadruple 
 
 
 
 

 

 
Richard Harshaw
Star: Sigma Orionis [48 Ori; STF 762; Bur 1032; ADS 4241] 
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): 0410 on 12/31/99 
Site classification: suburban 
Sky conditions: 
seeing-- 8 out of 10 
transparency-- 8 out of 10 
limiting visual magnitude-- 5 
Temperature: 39 F 
Telescope: Celestron C-8 
Eyepiece: Micro-Guide (160x) with 2.48x Barlow (397x total) 		 I made five sets of measurements with the Micro-Guide illuminated reticule eyepiece and got an averages of 13.8" at PA 84 and 11.8" at PA 237. (If you want the measurements themselves, reply to this posting.) The 7.5 mag star was rather difficult to measure. 

I noted colors of bluish-White, bluish-White, and deep Blue. This is a wonderful field and very rich! 

The A star is a close binary (0.25") with a 170 year period (Heintz, 1974) and 35 solar masses (the most massive of visual binaries). The distance between A and B is at least 20,000 AU (1/3 light year). 

The C star is rich in helium. 
The whole group is part of the Ori OB1 Association. 
Hipparchos/Tycho data show different distances for these stars; they may be an optical systsem. 

Measurements from 1960: 
3.8m (O9V) primary 
6.0m companion, 13" at PA 84 
7.5m companion, 11" at PA 236 
 

 
Luis Argüelles
Star: Sigma Orionis 
Date & Time:  January, 1, 2000 18:50 UT 
Seeing:  7 <1-10 Seeing Scale (10 best)> 
Location of site: La Olla, Gijón, Spain 
Site classification: Suburban 
Sky darkness: 4-4.5  <Limiting magnitude> 
Temperature: ~ 4C 
Telescope: Televue Ranger 70mm, f/6.8 mounted over a Manfrotto video tripod 
Magnification: 24x, 48x 

 		 In order to locate this star, first I observe M42, then I go up North until reaching NGC 1981. Now it's only a question of going towards Zeta Orionis (Alnitak) finding Sigma soon in the way. 

With this aperture and from this location, components A,B and D are easy at 48x and are almost aligned. I'm not able to observe component C at Mv=10 with this aperture/location combination. 

If SAO 132412 and Struve 761 form respectively the tip and base of "The big Orion's arrow", Sigma is shaped by the "horizontal" points into the arrow. The sketch represents the field of view at about 60x. 
[see also my log of Struve 761] 
 

 

 
Bill Becker
Star: Sigma Orionis 
Location of site: Casper, Wyoming Elev. 5200' 
Date of observations: 01-03-2000 10:20pm Mst 
Site classification: Suburban 
Sky conditions: 
Seeing:6 
Transp.:5 
Telescope: Quantum 4 Maksutov 
Magnification: 85x 
 

Star: Sigma Orionis 
Location of site: Casper, Wyoming Elev. 5200' 
Date of observations: Jan. 24, 2000 4:05 UT 
Site classification: Suburban 
Sky conditions: 
Seeing:4 
Sky Darkness: 4.5 
Telescope: Vixen 102 FL 
Magnification: 102x 
 

 Sigma Orionis is one of my favorites. Primary appeared blue-white, B & 
C were both noted as deep blue. 
 
 
 
 
 
 
 
 
 
 

I was able to see 4 stars tonight, as I had longer moments of steady seeing. I used 9mm Pentax & 2x Barlow for 204x. The primary appeared white, with the 2 brighter companions blue, no color in the 10th mag one. 
 
 
 

 

 
Rik Hill
Star: Sigma Orionis 
Date & Time: UT, 2000-01-05~0700 
Seeing:   <1-10 Seeing Scale (10 best)> 
Location of Site: Location: Jim Loudon Observatory 
   Longitude:110.77554 deg. W  or  110 deg. 46' 31.9" 
   Latitude:  32.18006 deg. N  or  32 deg. 10' 48.2" 
   Height above sealevel: 2875 ft. 
   see: http://www.lpl.arizona.edu/~rhill/jlobs.html 
Site Classification: Suburban/Rural 
Sky darkness: 5.5-6  <Limiting magnitude> 
Telescope: C11, C5 
Magnification: 152x, 181x 
 

 

 Separation (Clear or Toughing): very clear in C11 
Magnitude Comment: All four components to this visual system easily seen in C11 but only three in C5. Good diffraction pattern around bright stars in C5 but seeing smeared this out in C11. 

Color Comment: Primary bl.wht., others grey 
General Comment: This is a favorite of mine, and I guess I'm not alone.   The field is beautiful. I first observed this in 1963 after reading about it in Webb's CELESTIAL OBJECTS FOR COMMON TELESCOPES. Several faint stars were seen between Sigma and the triangle of stars (noted in Webb's) that follow this system. 
 
 
 
 
 

 

 
Richard Bise
Star:Sigma Orionis 
Date & Time: January/7,8/2000 
Seeing: 5 <1-10 Seeing Scale (10 best)> 
Location of site: 20 NW of Tucson Az
32.884N -110.979W
Site classification: Suburban 
Sky darkness: 4  <Limiting magnitude> 
Telescope: 10 inch Meade Dobsonian
Magnification: 49x, 125x (25mm Meade  and 9.7mm Plössls)
 		 The 10.3 Mag companion was not seen. My sense of the colors was too different between 49X and 125X for me to report. I'll have to work on this one! 
 

 
Orlon Petterson
Star: Sigma Orionis 
Date & Time: 12/01/2000, From ~10hr UTC to 11:30
Seeing:  4-7, improved as the evening progressed <1-10 Seeing Scale (10 best)> 
Location of site: Christchurch, New Zealand  
Site classification: Suburban 
Sky darkness:   <Limiting magnitude> 
Telescope: C102HD f/10 refractor  
Magnification: 28x 50x 100x 208x		 3 of 4 stars visible at used magnifications, however there were hints of  the 4th star at the lowest power, next to the glare of the brightest star.  Since I'm not sure where the 4th star is suppose to be it may just have  been the glare giving a false impression. 
 
 
 

 

 
Jordi Viver
Star: Sigma Orionis 
Date & Time: 19/01/2000, 21:45 UT 
Seeing: 6 <1-10 Seeing Scale (10 best)> 
Location of Site: Vic (Spain) 41º55’N, 2º19’E 
Elev. 570m 
Site Classification: Suburban 
Sky darkness: 4.7 <Limiting magnitude> 
Temperature: 1ºC 
Telescope: 200mm self-made Newton, Dobsonian 
Magnification: 48x 
 

Star: Sigma Orionis 
Date & Time: 9/02/2000, 23:45 UT 
Seeing: 8 <1-10 Seeing Scale (10 best)> 
Location of Site: Vic (Spain) 41º55’N, 2º19’E 
Elev. 570m 
Site Classification: Suburban 
Sky darkness: 5.29 <Limiting magnitude> 
Temperature: 0ºC 
Telescope: Celestron C8 
Magnification: 162x, 321x 

 Color comment: The A and B components are white, the C component are yellow. 
Separation: Dificult to separe A and C. 

Catalog data: Guide7.0: A3.80, B6.58, C 6.59 D(A-B) 41.5’’, D(A-C) 12.9’’, D(B-C) 30’’, PA(A-B)62º, PA(A-C)84º, PA(B-C) 232º 
WDS: (1994) A4.0, B6.0, D 0.3’, PA 125º 

General coments: The Moon has 13 days. Sigma Orionis is a nacked eye seen star. 
 
 
 
 
 
 
 

Separation: At 321x I can see four components, is very beautiful. 
 
 
 

 

 
Philippe de Jocas 
Star: Sigma Orionis 
Date & Time: January 22, 1h00-7h300 UT 
Seeing: 3-4 <1-10 Seeing Scale (10 best)>.
Location of site: Ottawa/Hull, Canada
Site classification: Suburban 
Sky darkness: 4.5 <Limiting magnitude>
Temperature: -25C 
Telescope: 6" f5 newtonian
Magnification: 90x, 120x
 		 Sigma Ori and Struve 761 could both be resolved  at 90x, but gained a lot by beeing seen at 120x, Sigma 761  coming across, with the slight mag. difference, as a nice cat's eye.

 
John M. Ryan
Star: Sigma Orionis 
Date of Observation: 23/1/00 at 10:40UT  
Location of Observation: Ciudad Rodrigo, Salamanca, Spain 
40º 36' N, 6º 32'W, Elev. 800 Meters 
Seeing: 4 (1 - 10, 10 best)  
Site classification: Urban
Limiting Mag. (naked eye): 3-4 with almost full moon 
Instrument: TeleVue 101 Apo refractor  
Magnification: 60x, 180x 		 Separation (Clear or Touching): Clear 
Magnitude Comment: Magnitues seem to be in agreement with listed values. 
Color Comment: The outside two were pale blue with the center one somewhat yellowish. 

General Comment. At 180X I had this multiple spit into three stars oriented in a NNE direction with the dimmer component in the center. From the data there is a fourth much dimmer component that I could not see. To the west in the same field of view there was a pretty close double that made the total group very interesting. Will have to return to this area. 

 
Jim Brownfield
Star: Sigma Orionis 
Date & Time: 26/01/2000, 6:30 p.m.- 11:30 p.m. EST 
Seeing: 3 – 5 (improving) <1-10 Seeing Scale (10 best)>.
Location of site: Huntsburg, Ohio, USA
Site classification: Suburban 
Sky darkness: 6 mag., could see ST 855, going to 5th mag. star Rho  <Limiting magnitude>
Other observing conditions:  83% humidity, 16 degrees F. with 12" snow on ground going to 84% humidity, 4 degrees F.
Telescope: 13.1"/F4.5 Dobsonian, with 5" aperture mask for the brighter pairs
Magnification: 47x

Star: Sigma Orionis   
Date & Time: 1/29/00, 3:30 UT - 10:00 UT 
Seeing: ) 3 improving to 4 <1-10 Seeing Scale (10 best)>.
Location of site: Huntsburg, Ohio, USA
Site classification: Suburban 
Sky darkness: 4.5 (limiting magnitude)
Other observing conditions: 14 degrees F dropping to 6 degrees F, 92% humidity
Telescope: Meade 80mm/ f11
Magnification: 28x

 split all at 47x, noticed ST 761 split in same low power field 
 
 
 
 
 
 
 
 
 
 
 
 

at 28x could make out 3 stars, went up to 187x but failed to find 10.3 mag star, which I feel was underneath the first diffraction ring of the primary 
 

 
Daniel Rodríguez
Star:Sigma Orionis  
Date & Time: 1/30/2000, 22:00 (UT)  
Seeing: 5 <1-10 Seeing Scale (10 best)> 
Location of site: Jerez de la Frontera, SPAIN, elev. 24 m 
Site classification: Urban 
Sky darkness: 4  <Limiting magnitude> 
Temperature: 9C 
Telescope: Celestron G8 (8” SCT f/10)
Magnification: 81x, 119x (Celestron SMA 25 mm, Plössl 17mm)
 
 		 A beautiful system split without problems at 81x, but best seen at 119x. The fourth component is visible with my G8 even from a very light polluted site. The wide range of magnitudes displayed by this multiple star system makes a very pleasant view. On the image, Sigma Orionis is located at right. 

 
Jay Zimmerman
Star: Sigma Orionis 
Date & Time: 02/08/2000, 0420 UT 
Seeing: 8 <1-10 Seeing Scale (10 best)> 
Location of Site:  Carbondale, IL, USA 
Site Classification: Suburban/near rural 
Temperature: 30°F (-1.11°C) 
Sky darkness: 5.3  <Limiting magnitude> 
Telescope: 97mm, f7 apo 
Magnification:  26.7x, 80x 

 

 Clean split of AB, D, and E at 26.7x. C needed 80x, probably due to low magnitude. AV not needed for C, which says a great deal about the high quality of the sky conditions.  Colors: AB and D = yellowish white; E = bluish white; C not determined.  This is a great 
system - beats the Trapezium, in my opinion (except when E is visible). 
 

 

 
Eddy O'Connor
Star: Sigma Orionis 
Date & Time: Feb. 17 2000, 9 p.m. local, 8 hrs GMT 
Seeing: + 
Location of Site:  South Coast New South Wales(E150.37;S34.52), Australia 
Site Classification: Suburban near water. 
Temperature: 18 C 
Sky darkness: 4.5(2 days to Full Moon)  <Limiting magnitude> 
Telescope: 25X100mm Binoculars and 16" Dobsonian, 
unaluminised and not fully figured and- what the heck- poorly collimated at this stage! 
Magnification:  25x, 60x (telescope) 		 Seven stars easily seen in Binocs, six in telescope. Sigma ice-blue in colour, companion colourless; Wide double East in Field had a noticeable pink secondary. Western double at some distance easily split in binocs but not in 16". Moon washed colour estimates out and ageing eyes tend to see green tints in most blue/white stars. 

Ambience: Tawny owls about, mosquitoes held at bay with RID cream and cat comes over to investigate but makes little comment. Moon looks  great in plain glass. 

 

 
Mark Brickley
Star: Sigma Orionis 
Date & Time: 18th february 2000 19:00-19:25 UT 
Seeing: 6 but with intermitttent cloud <1-10 Seeing Scale (10 best)> 
Location of site: Somerset, Uk 
Site classification: Suburban with significant local light pollution and with almost full moon
Sky darkness: 3 <Limiting magnitude> 
Telescope: Televue TV85  
Magnification: 47x, 90x (13mm Nagler and 7mm Nagler)		 Resolved the primary and the two brighter components, barely at 47* and  clearly at 90* but could not detect the fainter fourth component. This accords well with a previous couple of observations I had made of this star using the same equipment a couple of weeks previous while warming up to the 33 double project. 
 
 

 

 
Tim Leese
Star: Sigma Orionis 
Date & Time: 19-Feb-2000, 1900-2330 UT.
Seeing: 5/6  <1-10 Seeing Scale (10 best)> 
Location of site: Cheshire. UK
Site classification: Suburban 
Sky darkness: 3 <Limiting magnitude> 
Conditions: High haze, very cold and frosty, sky clearing later but full moon. 
Telescope: 200mm f/6  Newtonian scope  mounted over a Vixen GP mount (manual slow motion).
Magnification: x48, x240		 Split into 4 stars at x48.  Attempt drawing view  at  x240 
 
 
 
 

 

 
Bill Reinehr
Star: Sigma Orionis 
Date & Time: February 27, 2000, 03:30  UTC
Seeing: 7  (fairly still) <1-10 Seeing Scale (10 best)>
Location of site: Pflugerville, Texas, USA  (30 degrees N.)
Site classification: Suburban 
Sky darkness: 4.1 <Limiting magnitude> 
Temperature: 53F. 
Telescope: Vixen 80mm Fluorite, f/8  on Custom D altaz mount 
Magnification: 29x, 91x, 183x
 		 No luck on the Mag 10 component at any magnification. Struve 761 easily seen in the same FOV. 
 
 
 

 

 
John Clemmer
Star: Sigma Orionis 
Date & Time: March 6/2000 1930 EST  
Seeing: 7, quite steady <1-10 Seeing Scale (10 best)>
Location of site: Priceville, Ontario, Canada
W80 41'41"  N44 10' 40"
Site classification: Rural 
Sky darkness: 6+/10ths 5th mag. if I'm lucky tonight <Limiting magnitude>
Telescope: Televue Pronto
Magnification: 12x 
 		 40mm 12x

 
G.E.O.D.A Group
Star: Sigma Orionis 
Date & Time: 10-III-2000, 19:00-21:00 UT
Seeing: 7.5 <1-10 Seeing Scale (10 best)> 
Location of Site: Manises, Valencia, Spain. GPS coordinates: 39º 29' 36" N, 00º 27' 56" W.
Site Classification: Urban-Suburban
Sky darkness: 3 <Limiting magnitude> 
Telescope: Meade 10" LX-200 SCT
Magnification: 200x		 Published measures are the mean of two observations made from two different observers.

d = 15.3-15.3-49.3; PA = 86-242-64