Three CMEs hefted streams of protons and electrons from the Sun on the 18th, 19th and 21st of June to reach Earth on the night of 22/23rd June as a severe (G4 class) geomagnetic storm. Two of the 3 arose from AR 2371 which was Earth facing.
The short Summer nights aren’t ideal for aurora imaging but I was keen to give it a go – the Irish weather has been particularly miserable recently – hence the lack of me imaging AR 2371.
I set off at 0030 hrs BST with my phone apps telling me that the Kp = 8 (good) but that the IMF Bz was Northerly (Bad). The magnetometer at University of Lancaster was giving strong readings (good) but there was a moderate amount of cloud about (bad).
I went to my favourite local spot which is just a few minutes drive away – it looks North over Lough Foyle towards Donegal.
I set up and waited; at about 0100 hrs BST, I noticed some pale grey rays of light over my head and started imaging then switched to the Northerly horizon. As usual, I could only see pale gray rays visually – it took the long exposures to reveal colour.
It was difficult to expose the horizon shots properly due to the Sun’s afterglow. The display only lasted about 15 minutes – apparently the Bz flipped from North to South at 0100 hrs allowing the stream of plasma from the CMEs to enter the atmosphere for just that time.
The red/purple features are singly ionised oxygen, the green is doubly ionised oxygen.
Canon 5D mark 2 with Canon 24mm f1.4 lens.
Images taken with 1 – 2 second exposures at ISO 1600 between f1.4 and f2.5.
I just spent this afternoon playing about with settings rather than rushing to catch images but did get these two. There was a lot of atmospheric turbulence so anything zoomed in was like boiling water.
Small hedgerow prom in Ha and Full Disc 6 panel mosaic in white light.
Equinox 120ED refractor
Baader Herschel wedge
Baader UV/IR cut filter
Skyris 274m CCD camera with TeleVue 2.5x PowerMate
Ioptron ZEQ25GT mount
Taken just outside my front garden looking over a very light-polluted road. I used a 24mm lens with circular polariser, but realistically I think a 50mm f1.4 would have focused in more on the clouds themselves rather than the “street scene”. Alternatively, I could use my 60Da (cropped sensor) which has a light pollution suppression filter fitted.
Canon 5D mark 2 at ISO 800, 2 sec exposure.
24mmf1.4L lens at f3.5.
Circular polarising filter.
First light for my new scope, an Equinox 120ED, which will replace the trusty Celestron 102A for WL solar and lunar work.
I have fitted the Equinox with a MoonLite focuser which is silky smooth and much more pleasurable to use than the “agricultural” focuser on the C102A.
I read that the long light path through the Baader Herschel wedge didn’t work well with the Equinox so
I removed the click-lock holder and attached the two filters inside the wedge to a Baader T2 to C adapter. This has a built-in screw fitting for a 1.25 inch filter so I put my UV/IR cut filter in that.
Cloudy day and no major sunspots but was delighted to get focus with about an inch of drawtube showing on the focuser. Thought I would leave Barlows and mosaics for another day.
I’m not sure if the Equinox will work well for CaK – I know I will have to stop it down to about 9cm to get it to work at f10 (120/900mm scope). I have a B1200 wedge which the manufacturer only certifies to 100mm aperture- yet another reason to stop it down. Even then, there might be a lot of spherical aberration but I will try it out and see. I wont dispose of the Celestron just yet!
A single 1000 frame sub, stacked in AS2 and just a little wavelets in RS6
The visible sunspot is AR 2356
C – bipolar group, one spot with penumbra
a – asymmetric penumbra -2.5 degree or less in N-S diameter
o – very few or none tiny spots between leader or follower.
The follower here appears just as a pore
Equinox 900/120mm ED refractor with MoonLite focuser
Modified Baader Herschel wedge (Photographic with Solar Continuum filter)
Baader IR/UV cut filter
Skyris 274m CCD camera
Ioptron ZEQ25GT mount