Why does the aurora season ‘end’ on Senja island in the summer?
Many people think that’s because the northern lights simply stops. In total actuality it never does…
Senja Island – Where our resort is located
Senja island is located roughly 250km North of the Arctic Circle at 69 degrees of latitude North. It is home to some of the most spectacular northern lights on the planet, because it lies right in the middle of the auroral oval. This donut-shaped ring around the poles of the Earth, where the aurora is created. The 2018-2019 aurora season was no exception to the rule. Even if we are in a period of ‘low auroral activity’ because of our place in the solar activity cycle, we have had absolutely tremendous aurorae this season.
All good things come to an end though. Why do we have to cut short such a wonderful season around April 15th? – That’s a question that you might have had after browsing our website and here’s the answer.
Believe it or not the following picture was taken on April 10th2019 at 1:00 am local time. The moon is setting over the mountains, but you might wonder why the sky is so bright in the middle of the night.
It all has to do with our location in the world. Think about it, we’re quite close to the North pole. During summer the Earth’s geographic North pole always tilts towards the Sun, to offer 24/7 day light! Being within the Arctic Circle (67 degrees North) means that in the summer, we get at least one night during which the Sun doesn’t set at all. Now being two degrees North of it, Senja gets one and a half months with the Sun always up day and night (roughly from late May till the beginning of July). Well why doesn’t the Aurora Borealis Observatory close for only this period then, you might wonder?
Credits: (https://www.timeanddate.com/sun/norway/silsand )
This simple diagram shows the distribution of night, twilight and day light throughout the year for our location.
‘You need to keep in mind that the aurora can only be seen during complete night time, astronomical and nautical twilight. It simply cannot be seen during day time and civil twilight because the sky is too bright.’
Night time offers complete darkness so it is of course the preferred condition to observe the aurora. During astronomical twilight you get a thin light on the horizon with a smooth orange gradient. Most of the night sky remains very dark with a lot of stars, and the milky way still visible. Thus allowing a very good view on the northern lights, should they appear. At nautical twilight the Sun is still below the horizon but starts getting higher and giving off more light. The brightest stars are still visible and you get a brighter twilight sky with beautiful colors.
The aurora can still be viewed if it’s strong but it becomes washed out by the brightness of the surrounding sky. When the sun gets even closer up to the horizon the sky becomes too bright. You can then kiss the aurora goodbye, even if it’s up there in the sky! When the sun is up, just forget it and enjoy other activities!
Why we close during summer
The chart above shows we lose complete night time around March 26thalready. We still have a solid 6 to 8 hours of twilight enabling you to still see the aurora, in the beautiful colors of deep twilight. Around April 14thwe lose astronomical twilight completely, leaving us only 2-3 hours of semi-darkness each night. Keeping our resort open after that date, would not be worth it for our customers. All they would see is a washed out aurora, and the time window is getting dangerously tighter by the day! We have to wait until mid-August to get the same conditions again, explaining why we re-open then.
First aurora of the 2018-2019 season on August 28th2018 in the bright twilight
In short the aurora is a phenomenon that happens year round but the late spring and summer bright nights prevent us from gazing at it. Knowing that there is aurora in the sky and not being able to see it might seem frustrating but we already get so many aurora sightings during the regular season. Besides we are vey happy to see the Sun after some months plunged into darkness. It helps us get ready for the next season starting already at the end of August 2019, and it promises to be a good one!