One of the most frequent questions we receive on Facebook is: is this a photo of the aurora? So in this blog post, we’re going to list a few questions that you should ask yourself to help determine if you’ve snapped a photo of the aurora.
Although not perfect, our alert levels should give you some indication of whether or not you’ve likely seen an aurora. Living on the south coast of England and AuroraWatch UK says “No significant activity”? Unfortunately, that’s probably not going to be an aurora you’ve photographed.
| Colour | Description | Meaning |
|---|---|---|
| Green | No significant activity | Aurora is unlikey to be seen from anywhere in the UK. |
| Yellow | Minor geomagnetic activity | Aurora is unlikely to be visible from the UK except perhaps the north of Scotland. |
| Amber | Amber alert: possible aurora | Aurora is likely to be visible from Scotland, northern England and Northern Ireland. Possibly visible from elsewhere in the UK. |
| Red | Red alert: aurora likely | It is likely that aurora will be visible from everywhere in the UK. |
An aurora simply isn’t bright enough to be seen during the day and it is also quite unlikely that an aurora will be visible, at least from the UK, during the hours around dawn and dusk. In fact, the most common time for seeing the aurora, especially from the UK, is during the hours of 9pm-12pm (though you may still see an aurora in the early hours of the morning). Of course, this also depends on the time of year as the long summer evenings may be too bright to see an aurora even at 9pm.
Stunning streaks of light, known as nacreous clouds, are not aurora but can be seen in the polar regions during winter. Perlamutra mākoņi, CC BY-SA
As you can see below, an aurora is generally not visible through cloud cover. So if it’s very cloudy, foggy or misty, you’ll probably not be able to see an aurora. Our simple check for this is: can you see the stars? If so, you’re seeing the night sky and clouds are not obstructing your view. If you can’t, then those pesky clouds are getting in the way and you won’t be seeing an aurora.
If you’re lucky, you may see an aurora through broken cloud but not through blanket cloud cover. Copyright David Baird and licensed for reuse under this Creative Commons Licence.
Especially when it’s cloudy, light pollution from the ground can look a lot like an aurora. Light from astroturf pitches and street lamps often reflects off the ground and up into the sky. This can make the clouds appear to glow, often in some form of green, red or orange light – much like an aurora.
#NorthernLights Over Southampton? @aurorawatchuk pic.twitter.com/7vUeT5d5W1
— Karl Corcoran (@karl_corcoran) March 8, 2016
A photograph of light pollution that looks an awful lot like an aurora. Posted on Twitter. Used with permission.
An example of light pollution (from a Hockey astroturf pitch) looking like an aurora. Credit: N. Case
Clouds move in a fairly predictable way: in whatever direction the wind is blowing. An aurora, however, can be quite dynamic. If you’re lucky enough to be underneath an aurora it can appear to shift and race across the sky. From the UK, though, we’ll generally see an aurora as a glow on the horizon. It’s likely to appear quite stable, perhaps as an arc, though its brightness might change a little over time. Quick random flashes are unlikely and suggest light pollution (e.g. cars).
The most common auroral colours are green and red/purple. The green will probably be the brightest part of the aurora, closest to the horizon, with the wide red/purple band above this. Other colours, such as pinks or blues, are possible but are rarer. Orange and yellow are not colours associated with an aurora and are most likely light pollution from streetlamps. Note that by eye, an aurora may appear more white/grey but will show up as other colours on your camera – this is due to the lack of sensitivity in the human eye and the exposure time of the camera.
An example auroral arc structure, visible from Bangor, County Down. Green light appears closest to the horizon with purple above it. Copyright Rossographer and licensed for reuse under this Creative Commons Licence.
The aurora form in an oval around the earth’s magnetic poles (aurora borealis in the north; aurora australis in the south). From the UK, an aurora will only be visible to the north. If you saw the glow in any other direction then it definitely was not the aurora.
Hopefully these few simple questions will help you identify if you were lucky enough to get a photo of the aurora. However, we know it can sometimes be tricky even with these in mind, so always feel free to post your images on our Facebook page. We have many highly experienced aurora enthusiasts who visit our Facebook page and they, along with the AuroraWatch UK team, are always happy to take a look at your pictures! We also have a Flickr pool of verified photos of the aurora taken from the UK, this can be a useful place to check your images against.
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