About a month ago we had another large solar storm that set of a memorable auroral display. I wrote up a report for the BAA and I reproduce it here: -
"I was initially unaware that an aurora was in progress on the evening of the 19th January. At about 21:15 UT I looked outside to see if it was clear, as I often do, in case I can start doing some observing. There was some light fragmented cloud about and stars could be seen through the gaps. What caught my attention almost immediately was that part of the cloud formation looking straight above my head looked like it was being lit by some sort of search light hidden amongst the clouds. It was very odd because I couldn’t see what the source of the light was and I began to wonder if it was some sort of laser beam or perhaps the forward landing lights of an aircraft or even the fuel dump of some rocket. It couldn’t have been the moon as its phase at this time was only one day past new and it had already set. I called to my wife as I thought it so unusual. The light was white in colour and as we watched it faded but then grew bright again slightly further south. I was perplexed, as I couldn’t understand it and I must admit that it gave me goosebumps.
When I went inside I had my answer because I heard my phone emitting a buzzing noise when it does when it receives an aurora alert. The Aurora Watch magnetometer at Sumburgh Head had just recorded an exceptionally large value of 1128.3 nT (compare this with the value of 950 nT that we had for the big storm on the 10th/11th May 2024). The significant alerts had started at 19:00 UT with a value of 347 nT and then 882.0 nT at 20:00. I grabbed my camera (a Sony RX100) and tripod and began taking pictures at 21:26 UT. What was clear was that the aurora was easily visible to the naked eye in the north. It was a bit like the coming of dawn in intensity (see the image below taken at 21:26 UT – this was 10 secs at ISO 1600, f/1.8 – and it is obvious that this image is over exposed).
Note that neighbours house was confusingly lit up by their multicoloured lights in this image and this had nothing to do with the aurora!
At this time the aurora took the form of a homogeneous arc with a strong pink/red arc lying above a green one. At the top of the image taken at 21:26 is the star zeta Ursa Minoris and this was about 42 degrees above the horizon in altitude and in the red arc. I am sure that the arc stretched well above this. The boundary between the red arc and the green glow beneath was at an altitude of about 27 degrees. 4 minutes later at 21:30 the red arc developed some rays (see the picture taken below – 4s exposure, other settings the same). This view is looking NNE.
Looking in a more easterly direction at 21:32 UT (see the photo below – still ISO1600, f/1.8, 4s) I spotted another of the green patches of light developing near the horizon and away from the main auroral arc.
These green patches came and went in the south from 21:38 UT to 22:00 UT. The patchy cloud had thickened somewhat in this direction. At about 22:09 my attention was caught by a large bright red area of sky that was developing in the NE (see the image below taken at 22:12 UT – ISO1600, f1.8, 3.2s).
The shape of the Big Dipper can be seen clearly to the left of this image. The very top of the picture is at an altitude of 67 degrees. The red light doesn’t seem to extend beyond an azimuth of 98 degrees. Following this more rays began to appear in the red arc (see the images below at 22:14 and 22:16 UT, respectively – same settings as before).
A large red patch began to develop at 22:17 UT looking slightly north of due west (see image below, same settings as before).
The shape of the constellation of Aries is to the left of it. This shows that the auroral arc stretched from due west to due east and probably up to an altitude of 70 degrees at least.
From about 22:30 UT the aurora began to dissipate, however it did continue to be visible. The magnetometer at Sumburgh Head was 550.2 nT at 23:00 UT and 548.8 nT at midnight. Although I stopped taking pictures after 22:20, I popped my head outdoors at 23:26 and 23:55 and it seemed that the aurora was still occurring reasonably strongly behind a much thicker layer of cloud. Judging from the spaceweather the auroral storm continued right through the 20th of January and into the morning of the 21st."
All text and images © Duncan Hale-Sutton 2026









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