Observing session on Friday 3 June 2016

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Conn Buckley
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Joined: Tue Aug 07, 2007 11:28 am
Location: Crecora, Co. Limerick

Observing session on Friday 3 June 2016

Post by Conn Buckley » Wed Jun 08, 2016 9:27 pm

Just to say thanks to Gordon and Dave for organising last Friday night's session at Colm's (?) place near Lough Gur and indeed bringing along their own scopes. I did not really expect to see too much given the time of year but a couple of bright ISS crossings and one predicted Iridium flare (thanks to Heavens Above site info) kept things going until it got darker. Indeed an unexpected second Iridium flare close to the declining path of the ISS on it's second crossing was a bit of a surprise wow moment.

I have not seen Mars 'live' for some time and was quite surprised that you could see any detail given it's low altitude.

After that it was a treat to see M13 and M10 (I think) through Dave's 20 " scope. The highlight though had to be something that I had never heard of , let alone seen, i.e. The Blinking Planetary Nebula. I believe its catalogue number is NGC6826. I cannot establish if it is in Lyra , Cygnus or some other constellation in that region.

The version of Starry Night Pro that I have gives the following description for NGC 6826: Many planetary nebulas produce a blinking phenomenon. The brightness of the 10th magnitude central star can overwhelm the eye and cause the surrounding nebula to disappear. When you glance away and observe the nebula with peripheral vision only, it reappears, causing the blinking effect. A larger scope (how large I wonder?) reveals the bluish-green colour of the Blinking Planetary's elongated disc. Photos reveal striking 'fliers' on both sides of the nebula.
I definitely observed the blinking effect and to my eye, through the 20", it was a bluish colour.

What other Planetary Nebulas give this effect and has anybody in the club tried to image NGC 6826 ? Perhaps the scope size required is a limiting factor?
I had to leave about 2 a.m. Did you stay much longer?

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Dave Lillis
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Joined: Sun Aug 05, 2007 10:02 am
Location: Limerick city

Re: Observing session on Friday 3 June 2016

Post by Dave Lillis » Sat Jul 02, 2016 1:01 am

Hi Conn,
We stayed until sunrise, was it 3.30-4 ?
I haven't noticed this blinking effect as strongly in other planetary nebulae.

I couldn't help notice how much better the planets got as the night went on, as the mirror cooled, I'm going to get some fans together to cool it down quicker.

Again, many thanks to Colm for letting us use his site.
Dave L. on facebook, See my images in flickr
Carrying around my 20" obsession is going to kill me, but what a way to go. :)

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