Over the past few nights, clear skies have allowed skygazers in some parts of the UK to see the Aurora borealis (or Northern Lights). In particular, northern parts of Scotland have been treated to some stunning displays.
During autumn and spring the chances of seeing this phenomenon is increased due, in part, to the angle of the magnetic poles in conjunction with the magnetic orientation of the solar wind. This results in enhanced geomagnetic activity, leading to increased chance of seeing aurora in the UK compared with winter and summer.
Why now?
There is an additional factor leading to an increase in the chance of seeing the Northern Lights at the moment.
The Sun goes through an 11 year solar cycle, from solar minimum, through solar maximum and back to solar minimum. We are now in the declining phase of the solar cycle following the solar max which occurred in early 2014. During the current phase of the solar cycle coronal holes that begin the cycle in the Sun’s ‘polar’ regions have now migrated towards the Sun’s equator, meaning they are on a similar line of latitude to the Earth (i.e. facing the planet rather than directed north and south out of the solar system). These coronal holes give rise to high speed solar wind streams that buffet the Earth, disturbing its magnetic field.
In other parts of the solar cycle these disturbances are largely as a result of coronal mass ejections, which can give larger magnitude disturbances than these high speed streams.
In late September 2016 a coronal hole led to the Aurora borealis being seen as far south as Lancashire along the northern horizon. This same hole has since rotated 360 degrees around the sun and is now in a similar position but has grown in size. The dark area on the images below show this coronal hole from late September and today (26 October 2016).
Coronal holes (dark regions) as seen on 29 September 2016. Image courtesy of NASA
Larger coronal holes as seen on 26 October 2016. Image courtesy of NASA
The strength of the disturbance directly relates to how far south the aurora is visible (or how far north if you are in the southern hemisphere), and of course you need clear skies to see it.
Assuming clear, dark skies, the aurora should be visible with the naked eye on the northern horizon from much of Scotland and Northern Ireland and possibly into northern England. Parts of Aberdeenshire may have the best chance of viewing the displays this week, with clearer skies than further west. Further south across the UK it may be possible to capture pictures of the aurora while facing the northern horizon with the use of long exposures on cameras.
Keep an eye on our space weather forecasts here and follow us on Twitter @MetOfficeSpace, if there’s a chance of seeing the aurora in the UK we’ll let you know.
The Met Office works closely with the British Geological Survey in Edinburgh to forecast these geomagnetic events and the BGS website provides to the minute information on the current activity levels as well as ‘Tips on viewing the aurora’. The BGS website includes a display of the aurora forecast model which is run by the NOAA Space Weather Prediction Centre, we are working on implementing this model at the Met Office.
Let’s hope for clear skies and plenty of beautiful displays – if you are one of the lucky ones let the scientists know by tweeting about it on Geosocial aurora.
Official blog of the Met Office news team 
Maybe a little pedantic on my part but this is the truth.
The solar cycle is around 22years not 11 as is commonly believed. A cycle or full period returns to the same or similar conditions so as the poles reverse at approximately 11year intervals then the full cycle is double the observed time of sunspot activity. However the numbering is associated with the half cycle.
Also the period of activity is never 11 years. It is less than this if the Sun is winding up, and more than this if the Sun is in declining phase as it is now.
The peak is also always double belled with a weakening between peaks at solar max. Cycle 23 second peak was late 2002, and this cycle second peak was 2014 as you reported. So we see an extended cycle (half cycle of 12 years not 11) indicating solar reduction.
Cycle 24 was low in UV throughout but the total solar irradiance (TSI) was higher than cycle 23.
Currently TSI is falling rapidly and UV levels are reduced. Current indicators suggest this quiescent period will be extended to a 14 or more year interval to the next very weakened period of activity.
We will witness first hand the effects of solar reduction upon circulation patterns and winter pole stability, and the Sun’s effects upon Arctic sea ice levels.
Interesting winter (or series of) coming up perhaps?
Hi Guys, Many thanks for using my Photographs, its such a privilege to be featured by The Met Office. I was wondering if there was any chance you could link to my article about the lights from within this blog post ??
https://www.whitby-photography.com/northern-lights-isle-skye/
I was posted to Kinloss as a Weather Observer in the summer of 1987. I saw my first aurora outside my bed and breakfast place at Hempriggs (a farmhouse close to the beach at Roseisle in Moray) one evening after supper in September of that year and was amazed. I’d always thought they were a static thing, but that was far from true as they seemed to be always in motion. As a Weather observer we had a code from the WMO to use when we observed an aurora (direction, intensity etc) which we religiously used even though after time you get a little blase about seeing one, because they were not uncommon. I imagined that on the shorter summer nights in the north of Scotland they would be less frequent, but not true, one of the best displays I saw was on an August night. Then the WMO in their wisdom decided to change the reporting of aurora, they didn’t in fact change it but just dropped the special group and the requirement to report it entirely. But now a days the Met Office forecasts the weather in space, and social media is alive with images and video of aurora, it encourages people to look into the sky and seek out aurora, which is a very good thing because a good display is something to see and memories of it will stay with you a long time. It’s only a shame that the Met Office weren’t slightly more interested 25 years ago about aurora, but of course we didn’t have the internet then and it was before such things as Facebook, Twitter and Space Weather. How times have changed.
I wish I knew that the aurora can sometimes be seen from northern England when I was a student at Lancaster University between 1977 and 1981 (living in Morecambe close to the sea-front during 1978-79). Probably my best chance ever to have seen it. And I was stuck indoors reading a book.