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PostPosted: Thu Oct 12, 2017 9:32 am 
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Location: Portslade, Sussex Lat 50deg 51min Long 0deg 13mins West
11th & 12th October 2017: 2310-2330 BST & 0255-0305 BST: Used 10x50 mono and 22x60 spotter. Conditions were very good, the evening rain-clouds having surprisingly cleared, with Last-Quarter Moon not rising till the end of the first session. The Moon was high in the East for the second session, but Aries was very high in the south, and the Moon did not interfere even then. The position was taken from a chart in an astronomy magazine, checked against "Heavens Above" and plotted on Map 79 of Uranometria. I worked up from Hamal (alpha Arietis), to a squashed-inverted- mini-plough" asterism which included stars 11, 14, 16, 20 and 21 Arietis. The last two acted as "pointers" down to a row of 6th & 7th magnitude stars. Asteroid [7] IRIS was between the lowest star and a triangle of fainter stars above. regards maf


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PostPosted: Fri Oct 13, 2017 1:13 pm 
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Location: Portslade, Sussex Lat 50deg 51min Long 0deg 13mins West
12th-13th October 2017:
2030-2110 BST. Despite light pollution and low altitude of target, it was possible to use the 22x60 spotter at the back-door to locate Hamal and most of the field stars and then asteroid (7) IRIS. Some movement was noticeable since last time. The asteroid could also be seen in 10x50 monocular when rested on the door-frame.
0035-0050 BST: Awoke to find the sky transparency was very good, but with swathes of foggy-cloud sweeping the sky from time to time. To the back-garden with 22x60 and was immediately able to locate Iris and its environs, and additional very faint field stars were visible, including an arrow-shaped or tiny waterjar-shaped asterism towards which the asteroid was moving. At 0045 BST the bright arc of the rising Moon could be seen between the bushes, then part of the Moon itself and by 0050 the foggy-cloud had completely covered the sky, and so I went in. It cleared once again later, so I popped out at 0125 BST with the 10x50 monocular in hand for a final look...then I went back to bed! regards maf
13th October 2017: 2121-2130 BST: Clouds began to clear. Used the 22x60 (as before) to locate (7) Iris, with little difficulty. Obvious movement from last sighting. Followed until 2130 BST but then fast-moving foggy-cloud rushed across the sky. This cleared again eventually but left a stubborn piece of higher, slower cloud just in the wrong place. By 2200 BST, this had moved off and so replacing the 22x60 with the Endurance 12-36x50, I took for a final look, and then went to bed. regards maf


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PostPosted: Sun Oct 15, 2017 9:30 am 
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Location: Portslade, Sussex Lat 50deg 51min Long 0deg 13mins West
15th October 2017: 0125-0142 BST: Awoke to find that the evening fog had dispersed and transparency was good. Aries was high in tHe south. Asteroid (7) Iris was easily found in 22x60, just below the lowest faint star of the "arrowhead or very small waterjar" asterism. 0445-0600 BST: Crescent Moon with Earthshine and near to Regulus, was in the east, so went outside again, this time withe Endurance 12-36x50 spotting scope on a light-weight tripod. With Aries now in the west, locating Iris required that I venture with the scope onto the small lawn, which was very wet. From there I could observe the asteroid over the roof of my house, which I did. It was also visible from the west-facing front-room window, without having to stand in the wet grass, so continued from there until 0600 BST. Iris was gradually creeping away from the lowest star of the tiny asterism. (This asterism is shown on Map 38 of the Interstellarum Deep Sky Atlas, about half-a-degree below the star labelled Sigma 240. It is also shown in Uranometria, with the stars being shown at about 9th or 9.5 magnitude.)

15th October 2017: 2110-2125 BT: Unusually warm, but with very poor transparency low down. I could jusy about make out Hamal with the unaided eye. Using 12-36x50 Endurance spotting scope from the backdoor enabled a view of the brightest field stars but not the "micro-waterjar", but Iris was clearly located now heading towards a little elongated asterism of a few stars. These stars are somewhat brighter than the previously mentioned asterism.
regards maf.

16th October 2017:0502 + 0520 BST: Large gaps in messy clouds, with only two possible views of Iris, using Endurance again from the lawn, and seen above the house roof, and also saw the "new" asterism. regards maf


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PostPosted: Tue Oct 17, 2017 10:40 am 
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Location: Portslade, Sussex Lat 50deg 51min Long 0deg 13mins West
16th October 2017: 2120 - 2125 BST: Fast-moving and messy clouds with large, clear gaps. Used 12-36x50 Endurance spotting scope to make a detailed sketch of asteroid Iris and the field stars (comprising the "minuscule Aries" asterism.)

17th October 2017: 0230-0240 BST: Sky perfectly clear. Used Endurance again from the lawn with Aries over the rooftop. This scope's zoom eyepiece is labeled 12x, 18x, 24x, 30x and 36x.
Iris and Hamal (alpha Arietis) now fit the fov when set to up to 24x.

18th October 2017: 2125-2130 BST: Sky clear above but very poor transparency below and could only just see Hamal with the unaided eye. Quickly took the 22x60 scope outside, located Hamal, then the brightest of the field stars and Iris, but within five minutes all was lost to cloud. regards maf.


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PostPosted: Wed Oct 25, 2017 3:30 pm 
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Location: Portslade, Sussex Lat 50deg 51min Long 0deg 13mins West
20th October 2017: 01338-o147 BST: Awoke to find that the rain clouds had parted, leaving a number of huge gaps. Quickly took out the 22x60 scope and found Iris. which was now beyond the mini-aries asterism. Within a few minutes the sky clouded over again and I went back to bed.
21st October 2017: 0602 BST: Aries low in the west and very soon in cloud. Used 22x60 from inside the house. A poor observation.
25th October 2017: 0500-0520 + 0530. An unexpected temporary gap in the clouds. Used Acuter DS65 with 32mm eyepiece giving 12x magnification. Hamal (alpha) and Sheratan (beta) do not quite fit this fov. Initially viewed from the back lawn and later from the front-room window. Iris had now shifted considerably, due to the "missing observations"'caused by the bad weather, to between Kappa and eta Arietis, and it also made a nice, flat isosceles triangle with Hamal and kappa. By dawn the clouds had covered the sky again.
25th October 2017: 1900-1915 BST: from bedroom window using Acutr DS65 with 32mm ep = 12x magnification.Ligt pollution bad and Crescent Moon low in the SW. Hamal, kappa etc located and then Iris. Noticeable movement since previous observation. Very soon was clouded out! regards maf


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PostPosted: Fri Oct 27, 2017 7:01 am 
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Location: Portslade, Sussex Lat 50deg 51min Long 0deg 13mins West
26th October 2017: 1940-1950 + 2010 BST: Intermittent cloud and light pollution from windows. However located Hamal, kappa and Iris from the back garden, using Acuter DS65, [first with 32mm ep (12x) and then using 25mm (15x)] . The two stars and the asteroid now forming an even flatter isosceles triangle.
27th October 2017: 0530-0610 BST. From the garden and then from the from windows. Very variable cloud but excellent transparency in the very large gaps. Iris still not quite in line with alpha and kappa but Eta, Iris and a 7.5 magnitude unlabeled star, in a straight line, with the asteroid in the centre.The area around the asteroid is currently bereft of any stars nearby as
Uranometria and Interstellarum shows. This was the best sighting of the asteroid for some time. regards maf


Last edited by mike a feist on Sat Oct 28, 2017 3:41 am, edited 1 time in total.

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PostPosted: Fri Oct 27, 2017 1:08 pm 
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Location: Lancashire
More nice observations Mike. Alas, trees prevented me from replicating your asteroid observations. But Orion, high in the south, looked bright in the clear predawn sky, using the 7X50 Chinon's and the 16X50 Swift Technar's through a side window.The Orion nebula was especially conspicuous. :D

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PostPosted: Fri Oct 27, 2017 9:40 pm 
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Location: New Farnley, Leeds lat 53.8N long 1.6W
Hello Mike, spotted Iris in 15x63 binoculars tonight, 2017 Oct 27, 21.30 UT. Very easy target about a degree and a half south of orange Hamal. I make it mag 7.0 or possibly a touch brighter. Regards Bob


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PostPosted: Sat Oct 28, 2017 9:14 am 
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Location: Portslade, Sussex Lat 50deg 51min Long 0deg 13mins West
27th October 2017: 1920-1950 + 2120 BST: Clear sky. Used Acuter 65 (15x) to see Iris again, continuing it journey through Aries.
28th October 2017: 0355-0450 + 0500 BST: Extremely clear sky, very damp & cool. Acuter DS65 finally "steamed up" and so then used Endurance 50mm (12x) from indoors, resting it against the window. Iris now heading towards an "L-shaped" asterism of 8.5 - 9.5 magnitude stars.
28th October 20017: 2100-2112 BST. Very "mucky" sky but surprisingly intermittent views of the various stars of Aries , plus Iris, were visible in the Acuter DS65 (15X). Hamal, kappa and the asteroid seemed more or less in-line with the distance from Hamal to kappa was much shorter than kappa to Iris. regards maf


Last edited by mike a feist on Sun Oct 29, 2017 7:53 am, edited 2 times in total.

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PostPosted: Sat Oct 28, 2017 9:29 am 
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Location: Lancashire
Regarding dew on your spotter Mike, have you considered making a dew shield of some sort? I have an ACUTER 80mm spotter, for which I made a retractable dew shield from a stainless steel coffee tin. I simply sawed off the base so that I was left with a tube. I lined the tube with black felt.

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PostPosted: Sun Oct 29, 2017 7:29 am 
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Location: Portslade, Sussex Lat 50deg 51min Long 0deg 13mins West
Hello Brian: The dewing problem was excerbated by bringing the scope indoors to continue to view from the front-room window once Aries was disappearing from behind the roof as seen from the garden. regards maf


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PostPosted: Sun Oct 29, 2017 10:28 pm 
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Location: New Farnley, Leeds lat 53.8N long 1.6W
Picked up Iris again tonight at 21.30 UT in the 15x63 binoculars. Motion is obvious in the 48 hours since I last looked. I'll put a couple of drawings of the star field on the gallery. Kind thoughts Bob


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PostPosted: Mon Oct 30, 2017 2:16 pm 
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Location: Portslade, Sussex Lat 50deg 51min Long 0deg 13mins West
29th OOctober 2017; [1816-1845] + [ 1915-1920] + [2105-2110] GMT: Used Acuter DS65 (c/w 20mm ep = 19x magnification). Sky was very clear but with bits of cloud bubbling up here and there. Initially Gibbous Moon (with terminator just reaching the Jura Mtns) caused some light pollution. Iris was approaching the "L-shaped" faint asterism but only the brightest stars seen due to low altitute and moonlight.
30th October 2017: [0040-0047] + [0445-0450] + [0500-0530] GMT. Extremely clear sky and Moon had set. Cool but no wind. Used initially Acuter DS65 (19x) from the back garden. All the faint "L-shaped" asterism stars visible. I checked the identification and magnitudes of these on the BBA Computer Section Asteriod Chart page. (I will list these at the end.) Later I used the Acuter 65 (19x) from the downstairs window until it disappeared behind a tree and then used the Endurance 50mm spotter (12x) rested against the upper window until dawning light. Iris is at opposition today!!
The stars of the asterism are listed as:-
T 1213 1484 1 @ 8.97
T 1213 913 1 @ 9.16
T 1213 1307 1 @ 9.75
T 1213 368 1 @ 9.81
T 1213 947 1 @ 8.3
H 9618 @9.21
Iris is given as 6.9 magnitude.
regards maf


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PostPosted: Mon Oct 30, 2017 3:53 pm 
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Iris should be visible to good unaided eyes from a very dark site.

I wonder if I could have seen it when younger from La Palma at nearly 8,000ft.
I certainly was able to see mag 6.8 stars at about 30 degree elevation from La Palma in my late 40s. I was told it wasn't a particularly good night as there was Saharan dust in the air.

Regards,
David


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PostPosted: Tue Oct 31, 2017 6:44 am 
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Location: Portslade, Sussex Lat 50deg 51min Long 0deg 13mins West
30th October 2017: 1840-1915 GMT + 2120 GMT; Brilliant Gibbous Moon rather interfered, but Iris was seen and the two nearby stars (at given magnitudes 9.1 6 and 8.97). Increasing the magnification from 19x (20mm ep) to 24x (15mm ep) on the Acuter was of little help. At 2120 GMT, once the Moon had disappeared behind the house, the field stars were somewhat easier to see.
31st October 2017: 2236-2243 GMT: Early in the evening the sky was impossible for observation, showing only a very murky Moon, but before bed it was improved enough to allow me to just locate Hamal, Sheratan, kappa and Iris in the Acuter (x19).
1st November 2017: 0320-0325 GMT: Lots of clouds and lots of gaps. Viewed from the front-room window with Acuter (x19) Transparency was much improved. The field stars of Hamal (alpha), kappa, star T1213 1621 1 (magnitude given as 7.21),a H9307 (magnitude 5.89), and Sheratan (beta), make a slightly flattened "W". An extended lne from Sheratan (beta) to star H9307 pointed to Iris. Iris was now under the "L-shaped" asterism.


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