| James T. Hudson | ||||
| Star: Antares
Date & Time:Saturday, June 20, 1998 Seeing: 8 <1-10 Seeing Scale (10 best)> Location of site: USA Site classification: Suburban Sky darkness: <Limiting magnitude> Telescope: 4" Vixen Achromatic Refractor Magnification: 307x |
Seeing was good and transparency was fair (6). Antares was a
very bright yellow and its companion looked blue green by comparison.
The companion was outside the first diffraction ring but was involved in
the remaining rings and glare given off by the primary. Usually looking
somewhat fuzzy, the companion would sharpen to an airy disk at moments
of steady seeing and then both stars showed sharp disks. Very pretty pair.
Colors: Yellow/Green |
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| Luis Argüelles | ||||
| Star:
Antares
Date & Time: 7 July 1999 : 21.10 UT Seeing: 8.5 <1-10 Seeing Scale (10 best)> Location of site: Noja, Spain Site classification: Sburban Sky darkness: 3 <Limiting magnitude> Telescope: 4" Vixen Achromatic Refractor Magnification: 263x (Eudiascopic 3.8mm) Star: Antares Date and Time: 19, July, 2000. 21:38 UT Seeing: 7.5 <1-10 Seeing Scale (10 best)> Sky darkness: 3.5 <Limiting magnitude> Transparency: 4-5 Temperature: 17C, light breeze Location of site: Quintueles, near Gijón, Spain Site classification: Suburban Telescope: Vixen 102M, 4" achromatic refractor Eyepiece(s): Eudiascopic 3.8mm Magnification(s): 263x |
Located only 19 degrees over the horizon, I got the split
observing the secondary almost like an illusion, but definitely present.
I visually estimate a PA of about 270 degrees. Next day, consulting my
books, I confirm this data.
This is one of the most difficult doubles I have ever split. The difference
in magnitude from the components, but specially the low altitud in the
sky from my latitude makes the observation of Antares really a challenge
for any telescope. Good seeing is a must in order to get the split of this
beautiful pair.
Anyway, tigh and difficult to split doubles need always the best focusing
efforts. Long focal relations help a lot in this issue, and fast telescopes
up to f/6 are (with rest of conditions equal) more difficult to use.
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| Pino Bandini | ||||
| Star: Antares
Location of site: Ravenna, Italy Date of observations (UT): 20 June 2000 – 20.56 Site classification: Urban Sky conditions: Seeing: 5 (10 best) Temperature: 24C Limiting visual magnitude: -- Telescope: Celestron C8 Magnification: 125x (eyepiece 16 mm Erfle) + diagonal |
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| Patrick J. Anway | ||||
| Star: Antares
Date & Time: June, 23, 2000 03:00 UT Seeing: 6 <1-10 Seeing Scale (10 best)> Location of Site: Munising Michigan USA Site Classification: Rural Sky darkness: 6.2 <limiting magnitude> Sky condition: No moon; no clouds Temperature: 70*F, 21*C Telescope: Zeiss Telementor 63mm, f/13.3 & Vixen 102/1000 f9.8 refractors on equatorial mount Eyepiece: Vixen 12.5mm, 9mm, 6mm orthoscopics (with OIII filter) Magnification: Zeiss - 67X,93X,140X Vixen - 80X,111X,166X |
I have not been able to split Antares prior to tonight.
However tonight I was able to, using a Lumicon OIII filter (I read this
tip on another egroup) I first tried again in twilight and after, without
the OIII and I was still unable to split it. I then used the OIII on the
Vixen 4" and a 6mm ortho. for 166X and there it was, easily split and constant.
I could still see the first diffraction ring in the darkened primary and
it was just beyond the first ring; just about touching it. I tried a 9mm
ortho for 111X and it was still easy to split. I then tried a 12.5mm ortho
for 80X and it split, but blinked in and out. I thought - this is too easy,
so I got out my 63mm Zeiss. First I tried the 6mm ortho without the OIII
and could not find the secondary in the glare; and I now knew where to
look. I put the OIII in and there it was cleanly split at 140X. I then
tried the 9mm ortho for 93X and I was also able to split it, but once again
it blinked in and out. I am not sure if the color estimates are of any
use, but using the OIII, the primary was deep red and the secondary was
blue.
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| Eddy O'Connor | ||||
| Star: Antares
Date & Time: Sunday July 9th 2000 Seeing: 5 <1-10 Seeing Scale (10 best)> Transparency: 9/10 Temperature: 14 C Location of Site: Terara, New South Wales, Australia, Long.150.38 degrees; South 34.52. Site Classification: Suburban Sky darkness: -- <Limiting magnitude> Instrument: 16" F5 Dobsonian Magnification: 114x. Eyepieces: 30mm K, 18mm Celestron Ultima, 10mm Plossel. |
15 minutes after civil twilight, four stars visible: Alpha
Centauri, Canopus, Arcturus and finally Antares, at altitude 39.20 degrees.
Antares elongated but not split with 30mm eyepiece. Complete split at X114 with 18mm.With 10mm eyepiece image was too distorted. I was surprised at the easy split. The colours were interesting on the clear glass mirror: Deep yellow and light yellow, with boiling image on primary but sharp image on companion. I immediately dragged out the 8" and just managed a split at X144, but both stars distorted and colour hard to estimate. Later, as dark approached the secondary disappeared on the 8" but remained on the 16". I still managed to spot the secondary even with 2/3 of the 16" mirror covered. Ambience: Viewing stars in daylight brings its own pleasures. No lights
to worry about, or hidden objects underfoot or dew soaking the shoes. The
Moon, just past first quarter, made a great optical alignment tool. The
mighty Ptolemaeus was just receiving its dawn light and this amazingly
striking crater appeared mottled and dome-shaped in the early sunshine.
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| Tim Leese | ||||
| Star:
Antares
Date & Time: 11-July-2000( 20:30-21:30 UT ) Seeing: not measured Location of site: Cheshire. UK 53° 15' N –2º 33' W Site classification: Suburban Sky darkness: Dusk Telescope: 80mmD F/5 refractor Magnification: X160 (5mm Vixen Lanthanum + X2 Barlow)
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Antares looks to be about 10-15deg above the horizon at
this time of year in these parts and from where I am it can be observed
for a short period from early dusk to twilight.
In the past I have observed Antares with binocs as it only appears out of the tree/bush line for a very short time. This year however, as an experiment, I used my 80mmD F/5 refractor with my 5mm Vixen Lanthanum eyepiece and a X2 Barlow to give X160 magnification. To start with all I could see was a bubbling, scintillating red/orange star as expected but on closer inspection I could see a definite green colouration start to appear on the preceding edge of the star. Then, I realised that a very thin bank of cloud had passed over the view which seemed to filter out the brightness of the main star. The view changed and I observed, what I could describe as a horizontal snowman but with a greenish coloured head on a red/orange body!! Moving the star out of the field of view and letting it drift back into view again I could see the green component pop into view just before the main red/orange star. This was a very difficult exercise but I managed to repeat this a few times observing a very slight hint of black between the two components for what must have been microseconds each time. Unfortunately the thin cloud cover moved and the view reverted back to one scintillating star. Could I ask any members of the group, who have split Antares into
its colour contrasting components if my observation is a valid one? Or
were my eyes deceiving me!! ( Wishfull observing, perhaps!!)
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| Richard Harshaw | ||||
| Star: Antares
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): July 22, 2000; 0230 hours Site classification: suburban Sky conditions: seeing-- 8 out of 10 transparency-- 8 out of 10 limiting visual magnitude-- 4.5 mag Telescope: Celestron C-8 Magnification: 280x |
Magnitudes: 1.2, 5.4
Sep/PA's: 3" (decreasing) @ 275 (decreasing) Year of measurement: 1978 Distance (light years): 600 Luminosity (in suns): 9,800 Eyepiece and magnification: 280x. Colors noted: rO! and B. Split at dusk with a diffraction mask. Mask was rotated so companion popped out between two spokes of diffraction. Normally, it would sit on the second diffraction ring of the primary. Antares ("rival of Mars") has a diameter of 6.5 AU and the mass of 15 Suns. Antares is so large that if it was placed where the sun is, Mars would orbit halfway between the core and surface! It has an oval shape (deduced by lunar occultations, with a diameter of 0.041"), and is shrouded in a diffuse nebula (made of solid particles, not gas) some 5 light years in diameter. It is also an infra-red source. The "tiny" companion is 50 times as luminous as the Sun! It was first glimpsed in 1819 by Burg during a lunar occultation as it reappeared five seconds before Antares. It is, for some reason, under-luminous for its spectral type. Its spectral lines suggest very rapid rotation with a turbulent cloud surrounding it. It lies about 500 AU (6 times Pluto's orbit) from Antares. The orbital period, therefore, is something like 853 years, and viewed nearly edge on. Closest approach should occur in 2115 AD, when even the Hubble Space Telescope would have difficulty resolving them. Speaking of occultations, Antares is normally occulted in "seasons", often being eclipsed many months in a row. (Between 1967 and 1972, it was occulted on 64 consecutive months!) According to Baize (1978), the orbit takes 878 years. Antares is the brightest member of the Scorpio-Centaurus Association. This large group of early type stars is some 90 degrees in diameter, and includes most of the brighter stars of Scorpius, Lupus, Crux, and Centaurus. All the members of this group are moving toward the southwest to a focal point in Columba. Some 100 stars are known to be members, including Beta Cru, Sigma Sco, Epsilon Cen, Alpha Lup, Delta Sco, and the shell star 48 Lib. The Association appears to be about 20 million years old. In mythology, the scorpion's sting killed the giant hunter, Orion. To keep these mortal enemies apart forever, the gods placed them on opposite sides of the sky. First measure: 3.7" @ 276 (Dembowski, 1864). |
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| Penny Fisher | ||||
| Star:
Antares
Date & Time: July 23rd 2000 1:00 UT Seeing: 7 <1-10 Seeing Scale (10 best)> Transparency: -- Location of site: Englishtown NJ, 40.25 N 74.333 W Site classification: Suburban Sky darkness: 4.5 <Limiting magnitude> Telescope: 12.5" Discovery Dobsonian Magnification: 227x
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We were trying to split Antares (without a mask) and suddenly
Eddie yelled out "there it is, it's there!" But he declared it was blue.
I looked in the eyepiece. (Our scope was
near perfectly collimated by the way). On the telescopic western diffraction spike I was able to view a tiny, ashy-blue dot which wavered in and out of view. I was suprised that it was just lying on the diffraction spike as though cradled by it. Conditons did not allow us to double out our highest mag eyepiece, and as usual Antares was starting to waver in the turbulent summer air. Because the secondary did not jump right out at me, I am not sure if it was an optical illusion or not; and it was the same ashy blue-gray as the diffraction spike, not a deep or royal blue. If anyone can confer with if my observation is valid, please let me know.
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| Edward Otte | ||||
| Star:
Antares
Date & Time: July 23rd 2000 1:00 UT Seeing: 7 <1-10 Seeing Scale (10 best)> Location of site: Englishtown, NJ Site classification: Suburban Sky darkness: 4.5 <limiting magnitude> Telescope: Discovery 12.5 inch Dobsonian Magnification: 227x |
All I can say about it was I saw it. All I could tell
about it was a grayish presences.
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| William L. Schart | ||||
| Star: Antares
Date & Time: July, 2000 Seeing: 5 <1-10 Seeing Scale (10 best)> Location of site: Killeen, TX (Lat 31 N, Elev 600 ft) Site classification: Suburban Sky darkness: 1 <Limiting magnitude> Telescope: Orion 6" Dob. Magnification: 120x |
After numerous attempts, finally succeeded in splitting
this. I used my Hartman mask to eliminate the difraction spikes from the
spider, as apparently one of these was laying at almost the PA of the secondary.
The seeing was not very good after another 100+ day, but the secondary
was popping in and out while Antares itself put on a light show of almost
every color imaginable.
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| John M. Ryan | ||||
| Star:
Antares
Date of Observation: 3/08/00 21UT Location of Observation: Barraras, Salamanca, Spain 40º N, 6º W, Elev. 800 Meters. Seeing: 6 to 7 (1 - 10, 10 best) Transparency: 8 Limiting Mag. (naked eye): 4.5 Site classification: Rural Instrument: Televue 101 Apo Refractor Magnification: 180X (3mm Radian) |
Separation (Clear or Touching):Clear
Magnitude Comment: Large difference in Mag according to the data Color Comment: Light orange yellow and blue without filter. Deep orange red and blue green (turquoise) with OIII filter. General Comment: First tried splitting Antares without the OIII filter and could not see the comes. Installed Lumicon OIII filter and the secondary became very obvious. The color of Antares changed from a light yellow orange to a deep orange red and the secondary was a blue green (turquoise). The filter also gave a size relationship. Antares was large with the small secondary sitting along side like a plum along side a large apple or orange. The colors were startling with the filter. I then tried again without the filter and I would notice a hint of blue that would pop out of the light yellowish orange primaray when the seeing would settle down for an instant. I don't remember who suggested the OIII filter but it is a winner in these situations with doubles that have a great difference in Magnitudes and very close components. The biggest surprise was the intense color change. Going back and checking the 22 messages it looks like I have to thank PJ Anway for the OIII filter tip. |
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| Rafaello Braga | ||||
| Star: Antares
Date & Time: 19, August, 2000, 19.36 UT Seeing: 8 Pickering (12 best) Location of Site: Corsico, Italy Site Classification: suburban Sky darkness: not recorded Telescope: Vixen 4" refractor Magnification: 100x, 143x, 200x |
At 100x (SMA 10 eyep) and without any filter the comes
was invisible. At 143x (Vixen OR 7) I cleanly split the double (I wonder
how 43x can make a so big difference), the colors of the components being
obvious (orange and pale blue). With an 80A (pale blue) filter Antares
was quite easy, in fact very easy ! I was really astonished of this considering
the low altitude of Antares on my local horizon, the presence of extra
chromatism due to the atmosphere and the difference in brightness of the
two stars. I believe that the scope also played and important role in obtaining
this result. At 200x (Unitron OR 5 mm) the double remained easy but more
disturbed by turbulence. At this power plus a W11 (yellow-green) filter
(which is useful to suppress chromatism, even the atmospheric one) the
pair was very well splitted (with almost no black space between the components
due to the glare from the primary) but colors were not evident.
The OIII nebular filter gave an image too dim and with it the comes was no longer visible. Before to leave the scope to the mosquitos I gave a quick look at the
double-double in Lyra. It was my first observation of this quadruple star
through the Vixen refractor. Seeing was at his best (12 on Pick scale,
that is image absolutely steady). Well, I realized once more that a good
refractor - even with the limits imposed by a small diameter - is the very
best double star scope.
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