Observations of ABELL 12
These are the observations available for ABELL 12. If you have any of your own that you'd like to submit we'd love to put them on the website.
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Observations from Orion… at last
Last night I had my planetary head on mainly because Mike Wood had shown me his stacked video image of Abell 12 which was rather impressive and evidentially had impressed Owen Brazell too! After Mike showed me his image I went through my files expecting to find a drawing from some time or other but nothing!
I need to put that right so I went straight after Mu Orionis as I knew that Abell 12 lurked in the glare of this magnitude 4.1 star. I had the exposure of my Watec video camera turned down to 5 seconds and bang the ghostly round orb of Abell 12 aka PK 198-6.1 was obvious and striking next to the dazzling star with its large diffraction spikes.
An inverted sketch of Abell 12 by Dale Holt from his Chippingdale observatory in Hertfordshire. So to were Mu orionis Ab & Ba as this star is a 4 star multiple. I'm not sure if I could see the fourth member Bb as I had no idea where to look and as the faintest member it was most susceptible to Mu A's glare. Anyhow if I kept exposure relatively short then the other two were framed nicely between Mu A and Abell 12 adding to the spectacle considerably in my humble opinion.
Lengthening the exposure right up to 20 sec did nothing to enhance the detail seen in Abell 12 but it simply lost the multiple members in the glare and bloat of the primary. No central star was seen, mottling across the whole of the round and sharp edged planetary remained unaltered. The attraction of this PN is its ethereal appearance and contrast with its bright neighbour. A delight no less.
Next I went onto nearby Abell 14 another planetary with the PK designation of PK 197-3.1 This was to be a failure! This isn't the first time that I have tried and failed on this PN. It is very small 40"x27" and faint at magnitude 14. Tonight I had the location absolutely spot on but my camera could not pull it out even with a 25 sec exposure. It is obviously strong in the blue spectrum emission where my camera is less sensitive.
I dug out an old visual Lumicon 1.25 UHC filter and screwed this to the camera nose piece. I had to refocus and then I tuned the exposure up to 15sec then 20 sec with my fingers literally crossed but I could see not hide nor hair of this nebula! FAIL big style!
I then thought well I will leave the filter on and try the old favourite, NGC 2022, another planetary nebula in Orion and one I have been observing both visually and with video for 20 years or more. When the scope drive stopped NGC 2022 was bang in the centre of the field and strikingly obvious at 5 sec exposure. At 20 seconds it was incredibly detailed.
A inverted sketch of NGC 2022 by Dale Holt from his Chippingdale observatory in Hertfordshire. I dug out my file and looked at 3 previous sketches, better view tonight for sure 😀 I agonised over the sketch trying to show all the detail available. My new digital monitor is such that I can use a magnifying glass to study small objects and see yet more detail! I love it 😁
So that was 2hrs gone and time to get indoors and ready for bed, not that I slept! No,no way too excited.
Dale Holt - (11 February 2021).