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PostPosted: Mon Mar 25, 2019 3:00 pm 
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Location: Portslade, Sussex Lat 50deg 51min Long 0deg 13mins West
Or A Venus-In-Daylight marathon.
Monday 25/3/19, 0822 to 1355 UT: the sky was mostly clear with occasional bits of small cumuli. Later it was warm and sunny, with a cool breeze, although I was sheltered from this. I used a Olivon T50 spotter (12-30x50 on a tripod), at 12x magnification. At this magnification the planet looked like a bright star. The Sun was hidden by the yew tree for safety sake, and I spent much of the time carefully repositioning the tripod + scope to hide the Sun, until at the end I was squashed against the tree trunk and viewing along the brickwork edge of the house. By then the planet Venus was very pale and was finally lost when within the fov of the pylon cables on Southwick Hill. The first observation was at 0820 UT, and thereafter Venus was located every 10 or 15 minutes until the last view at 1355+. In between, I sat in the garden chair, browsed through an astronomy book or two and drank cups of tea! Duration = 5hrs 35mins. Regards maf (Obs. #568).


Last edited by mike a feist on Mon May 06, 2019 2:05 pm, edited 1 time in total.

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PostPosted: Tue Mar 26, 2019 7:28 am 
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Location: Galloway, SW Scotland
Venus and tea, perfect!

You must have to be careful not to lose track of where it is in the glare of lunchtime daylight!


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PostPosted: Tue Mar 26, 2019 10:17 am 
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Location: Portslade, Sussex Lat 50deg 51min Long 0deg 13mins West
There are a few knacks in following Venus in daylight and quite often I have had to move the tripod and then failed to relocate the planet. Firstly I use a low magnification with with a large fov and tripod mounted on a lightweight camera tripod. Currently the planet is quite low down which does make it easier as one is not trying to find it in a huge sky. Once found, within say ten minutes or so, the planet will move from one side of the fov to the other. Before culmination/ meridian transit it will be moving somewhat diagonally upwards across the fov. When due south it moves horizontally and afterwards moves somewhat diagonally downwards. So if you do not leave it too long between views, panning a little in the right soon nails the planet. Moving the tripod itself because the Sun is creeping across the sky and one needs to be in its shadow for safety, is the main cause of losing the planet especially is you do not do it often and if one has to change the surface on which it is standing. A little bit at a time is best. It one needs to make a big move, for example, from back to front garden, or from indoors to the garden, small bits of passing cloud or contrails can be very useful guides, or if the planet is low down, distant horizon pointers such as pylons etc are useful. Small bits of cloud or aeroplane + contrail are extremely useful to get the scope into good focus, on the odd occasion I have tried, desperately and despairingly, for sometime to locate the planet in a blue sky to finally realize that the instrument was not in good focus. Scanning a huge chunk of an empty blue sky for the planet, there is also the problem of getting ones eyes focused to infinity, passing planes or distant birds help here. Finally, the clearer and bluer the sky the better although once one has the planet focused in view, often one can still see it through the cloud. Watching small clouds pass across and by the planet always give me the impression that Venus rushing through the cloud, and not the cloud that is passing by.
Finally, some might say why not use a GOTO scope or at least use an Equatorial mount which would make it much easier. My answer would be "what is the fun in that?". Regards maf
PS. just tidied up some bloopers! maf


Last edited by mike a feist on Sun May 05, 2019 6:54 am, edited 2 times in total.

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PostPosted: Tue Mar 26, 2019 7:05 pm 
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Location: Galloway, SW Scotland
Thanks, Mike, I must give it a go sometime, tracking with my minimum magnification of 18x in my 4" refractor and increasing the magnification every now and again for a closer look. I must say, I love the variation in observing planets in different light levels, the way that different light levels accentuate different aspects of a particular planet. For example, I enjoy Jupiter immensely in the darkness of night, but around dusk I find the planet's curvature is more apparent.

Best wishes,

Nigel


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PostPosted: Tue Mar 26, 2019 7:55 pm 
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Location: Portslade, Sussex Lat 50deg 51min Long 0deg 13mins West
Following Jupiter into twilight and then daylight is not as so easy, although I was rather surprised just how the Galilean moons could still be seen in a small scope when the sky was not properly dark. The surface brightness of Jupiter is much less than Venus and the Jovian disk soon pales out to match the brightening sky and is easily lost from view. Daytime views of Venus when near to a very thin crescent or decrescent Moon can be striking and initially I was surprised to find that Venus is much easier to locate than the pale sliver of the Moon. Regards maf.


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PostPosted: Sun May 05, 2019 7:53 am 
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Location: Portslade, Sussex Lat 50deg 51min Long 0deg 13mins West
Venus in Daylight: Saturday, 4/5/19, 1120-1340 BST. The sky was very clear and blue with large and small white cumuli passing quicky in the cold north wind. The clear blue sky suggested that it would be s good time to find Venus again and to follow it from the garden. I used the Olivon T50 again at 12x on a light-weight tripod, the 45deg eyepiece being ideal as we shall see later. The first task was to find out just how far Venus was from the Sun and their different altitudes.

"Heavens-Above" produced the following: at the time that I began, 1120 BST, Venus would be due south (azimuth 180 deg.) at an altitude of about 44 degrees, and about 10 degrees lower that the Sun and about 27 degrees to the right of it. Usually I would have set up the tripod on the spot which would have the edge of the house on the Meridian but at this time that would have put the scope directing in sunlight, so for safety sake, noticed when a small cloud was south. quicky set up the tripod in the shade of the yew tree with the scope pointing to the small cloud. The scope was then roughly pointing south. As Venus was more or less at 44 degrees altitude, setting the 45 degree eyepiece horizontally, meant that I was almost there...just a small bit of panning etc very soon located Venus as a bright star, no phase being visible at the low magnification.

Once found it was only necessary to check every ten minutes or so, moving the scope slight to the right at first and the as time progresses right and diagonally downwards. Locate Venus at 1125 BST and thereafter at 1130, 1130, 1135, 1150 and 1200 BST. At the last time, Venus was lost in a large and rather dark cumulus cloud and it as also necessary to move the tripod further under the yew, to avoid the Sun.

Fortunately I managed to relocate Venus when it emerged from the cloud, and continued following the planet at 1220, 1230, 1235, 1240, 1245, 1255, 1305, 1310, 1320, 1330, 1335, 1338 and then 1340 BST. By then the deep blue of the sky had deteriorated to blue-white, Venus was just about to disappear behind the house roof and there was even a few spots of rain, so I went in. Between views of the planet during the session, I spent the time reading "Sky & Telescope", drinking cups of tea whilst sitting the the garden chair with my jacket on, as it was pretty chilly. One of the most interesting sights was watching the edges of small clouds passing over the planet with it looking like it was Venus racing through the clouds! (One.#569). Regards maf.


Last edited by mike a feist on Mon May 06, 2019 2:08 pm, edited 1 time in total.

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PostPosted: Mon May 06, 2019 9:59 am 
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Location: Portslade, Sussex Lat 50deg 51min Long 0deg 13mins West
Monday, 6/5/19, 0830-9845 BST: some clear sky but with cloudlet sheets, contrails, holey cloud sheets, and all together a messy sky. Wind direction now westerly. However Venus final found intermittently visible in and out of clouds, with nearly always some cloud in the fov of the T50 Olivon spotter. From the garden with the Sun hidden by the yew tree. (Obs.# 570). Regards maf


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PostPosted: Mon May 06, 2019 8:25 pm 
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Location: Manchester
Mike
I can only sympathise. I experienced frustrating problems myself today trying to observe & image the big bright SUN today. I think two layers of cloud drifting at different rates complicated things! But in the end it may have been well worthwhile possibly finding a surprise feature.
Best wishes from Cliff


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PostPosted: Tue May 07, 2019 6:05 am 
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Location: Portslade, Sussex Lat 50deg 51min Long 0deg 13mins West
Cliff, There is nothing worse that two layers of cloud...unless it is three! As the day progressed the contrails that scratched across the sky spread laterally by the upper winds to cover most of the sky with this manmade cirrus. Was also hoping to pick out the very thin crescent Moon after sunset but clouds put pay to that. Hoped to start is series of observations of Ceres having investigated its current location near Scorpius, but early this morning transparency was terrible.
The weather really never seems "to play ball" with us skywatchers anymore!
Regards maf.


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PostPosted: Tue May 07, 2019 10:12 am 
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You can lament the weather at your own site Mike, but its cloudier and wetter in the North-West. We occupy a shear zone, where the warmer air in the south, meets the colder air in the north, with its consequent stratospheric turbulence.
Added to this is the international air corridor directly overhead, with its vapour trails.

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PostPosted: Tue May 07, 2019 3:16 pm 
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Location: Portslade, Sussex Lat 50deg 51min Long 0deg 13mins West
Brian, Sounds grim! Of course, Gatwick Airport is just up the road from here and some mornings when conditions are just right (or wrong) the blue sky is scratched to pieces by contrails which eventually spread sideways to detriment of the clear sky. I am inclined to believe that the weather (or maybe the climate) really is deteriorating when it comes to skywatching! Regards maf


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PostPosted: Wed May 08, 2019 7:08 am 
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Location: Galloway, SW Scotland
Lots of clear skies here, of late...but....it is SO light! I think our sun sets only twenty minutes later than yours, Mike, but the twilight goes on and on and it never really gets properly dark. That said, I do enjoy it; that midnight glow from the north has a beauty.

I normally declare my season closed by about now until late August, unless there are planets around. I should be so lucky! All so near the horizon, this year. Perhaps I'll have the odd peep at the moon.

So the telescope is now just the playground of spiders. But I enjoy the summer and return enthused at the end of August.

Not that it is summery just now.... :? ...back to winter after a lovely, warm Easter week!


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