A real Challenge for this month. Many thanks to David Arditti and Tim Haymes for the work done on this.
https://britastro.org/node/22532
Let's hope we can see some interesting posts later in the month.
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Observer's Challenge - Occultation of Venus by the Moon, June 19
Mon, 2020-06-08 07:52
#1
Observer's Challenge - Occultation of Venus by the Moon, June 19
This is going to be a tricky one. We’d planned to try and observe the occultations of Venus, but I was undecided what filters to use, and I need to make a longer sun-shield.
James
Apologies that this event is not listed on the BAA Handbook Lunar Occ page, it should have been. A prediction setting that i used was incorrect. (Fixed now!). The omission was only noticed after publication.
I will be using an IR pass filter for imaging. For my mobile goto telescope it should be possible to set up the alignment with stars before sunrise. I might do that and keep the rig running. Early acquisition of Venus would be a bonus.
I've got a Skywatcher 90mm refractor I use for white light observation of the Sun with a Seymour solar filter or a Lacerta Herschel wedge, I do tend to use the Herschel wedge more than the Seymour filter. It's mounted on a EQ5 with a Synscan upgrade so I'll use that to align it with the pole and get it to find Venus without the Sun getting in the way. Clear-ish this morning so I hope the clouds stay away next week.
The position Venus will be in did pose a problem when I did a dry run this morning, the EQ5 upgrade wasn't carried out by me, it was there when I bought the mount. The RA axis has a black plastic block as part of the upgrade which at certain positions hit's another block on the Dec axis. You can guess what happened so I had to do a meridian flip to avoid the blocks, I think further preparation is required.
I will try and attempt this, weather permitting of course. Will experiment on the moon beforehand to see how well it comes out with different filters.
Excellent idea Peter, I hope you share the results of your filter experiments with us as I'm interested to know what different types of filter make during daylight too.
Yes of course I will. I have used Ha filters on the moon in daylight, but as David Arditti suggests a red filter might also be an option. If I get organised I will try different flters on both the moon and venus separately before they get to conjunction, and then capture the conjunction with whatever seems to work best.
I did some test imaging this morning of both the moon and venus. Both red and Ha filters worked fine, although I felt that the Ha was more successful - don't ask me why! The key thing is that the moon requires one tenth of the shutter speed of that venus needs. So the choice is an over-exposed venus or very faint moon. In my case the moon was best at around 0.3s with the Ha filter, and Venus at 0.03s. I'm tempted to try with both exposures on Friday, and then combine the images.
Saw it visually in the 9x50 finder. Absolutely fantastic, crystal clear blue skies. A very large, very thin, very faint ghostly crescent moon with a tiny but very bright 'c' of a crescent Venus next to it. I watched the crescent of Venus get smaller and smaller until it pinged out of existence behind the moon. Despite 40 years of observing, sights like this never fail to grab me.
Andrew
Clouded out for re-appearance. Meant to say despite 50 years of observing....think that was a Freudian slip to disguise my age :-)
Andrew
Very lucky. Clouded out for me and rained out...
Excellent Andrew. Well done!
Alas nothing but heavy cloud here.
Gary
Nice picture, alas rain here in South Wales
Yes, an amazing picture, and lucky, as it was wall to wall heavy cloud in the part of Spain where I am.
What a great picture, Peter.
I watched the Venus Moon Occultation this morning from sunny Spain.
See my images here
https://britastro.org/node/22733
https://britastro.org/node/22732
https://britastro.org/node/22731
Venus was brighter than I had expected and is a little over exposed. I couldn't make the exposures any shorter as the camera was already on its shortest setting.
Well done to everyone who captured the event!
Raining here unfortunately.
Michael.
What wonderful images of the event - thanks for sharing.
BAA member John Sussenbach in the Netherlands had good conditions, and produced this lovely video. From my location it was too cloudy.
https://youtu.be/8SS-yjY5Wak