Lapland Arctic Adventure Overnight Trip, December 09/10 2006
Last update December 11th 2006 @ 13:15
Introduction
Omega Holidays operate a number of speciality trips out of the UK with an astronomical theme. Examples
include flights to see total eclipses of the Sun (http://www.digitalsky.org.uk/solar/tse-20060329/tse.html)
and flights to see the aurora. One trip takes passengers to Finnish Lapland in search
of the Aurora Borealis or Northern Lights.
The overnight stay in Kuussamo (66N, 29E) on December 09/10 2006 was unfortunately hindered
by thick cloud and rain which meant that the Northern Lights were hidden from view. However, Omega's
Peter Truman promised the Arctic adventurers that he would have a word with the pilot of the
return flight home and ask whether a report could be made if lights were visible.
Obviously this 'extra' is at the discretion of the flight deck but on this occasion
we were extremely fortunate to have an extremely helpful captain.
With the cabin lights dimmed and with the kind assistance of the passengers, a lot of people got their
first view of the Northern Lights from the right side of the aircraft. Paul Money and myself (Pete Lawrence),
the two tour astronomers gave up their front row seats so that additional passengers could get to see
one of natures most beautiful displays. Although time was limited (the cabin crew kindly
held back on their normal duties to give us time and space to do ours) both Paul and I did manage to
stick our cameras against the aircraft windows and take a few shots of the aurora. As promised to the
passengers, these photos are presented here. Please feel free to download them for
non-commercial use if you wish.
Photographing The Aurora from a Plane
it's probably fair to say that photographing the aurora through a plane window is
a tough challenge. To capture the glow of the Northern Lights, the camera has to be
set to a reasonably high sensitivity and the exposures fairly long. On this occasion
the cameras were set to ISO1600 at full aperture with exposure times ranging from 4s
to 30s.
A plane is not a stable photographic platform. Turbulence or minor course changes
can play havoc with a 30s exposure. Also, holding a camera against a plane window without
tripod support isn't easy and minor shakes and movements are all too easy to introduce. However,
bearing this in mind, results can be had. The images presented below are shown as is (warts and all) and while
none of them can approach what can be achieved from the ground, they do act as a general
reminder of the aurora that was seen from the plane on the night of 10th December. Please note that the photos on this page may change over time
as I find time to process them and remove some of the unwanted artifacts.
The first shot taken is shown below...
Both Paul and myself had spotted the auroral arc as we climbed out of the cloud layer as a bright arc along the
horizon. There are a number of ways to determine that this is the aurora and not just a haze layer. For example
a sharp lower edge to the arc, small undulations along the lower edge and, a good giveaway, stars beneath the arc.
The above photograph was the final confirmation as the striking green colour (caused
by excited oxygen) could only come from the Northern Lights.
The bright wiggly lines on the image are stars, the wiggles being caused
by plane turbulence causing the camera's position to shift slightly during the 8s exposure.
A shorter exposure helps to keep the wiggles down but the result is fainter. In the 4s image shown
above, the result has been enhanced using a graphics application. This increases the intensity of
the image but also brings out more of the noise that was hidden in the picture (hence the grainy
appearance of the region just above the auroral arc). Note the non-uniform brightness of the
arc. Some patches of it were starting to show marked increases in brightness, even over a very short
period of time.
Moments later, things really started to kick off. An active aurora can change
dramatically over the space of several minutes. Here we can see a faint lower band,
visible at the bottom on the right hand side of the picture, and a complex curtain
structure towards the left. Another bright ray can be seen towards the extreme
left of the image. The 'seagulls' in the sky are, once again, stars caused by
camera movement during the 10s exposure. Visually, the display had a definite
green hue to it but it takes the longer exposure capabilities of the camera to really
bring out the colour as shown here. The orange 'fire' below the aurora are town lights.
Here is the bright ray forming. Rather a lot of turbulence on this particular shot but
the structure of the aurora is very evident. This was a 10s exposure.
Shortening the exposure time back to 4s allows the structure to be picked out better (there's less
time for the plane to wobble the shots) but at the expense of increased image noise. Whoever
said that astrophotography was easy?!
If your mind's eye picture of the aurora is of a light structure fixed in the sky - it's wrong! This
sequence shows small but obvious structural changes in the aurora. The time span for
this sequence of four shots is just 30s - i.e. the sequence shows how the aurora has changed
in just 30 short seconds!
Cabin Light On!
With the cabin lights back on, the bright glare meant that our view of the Aurora Borealis
was over. However, you can't beat an astrophotographer that easily! Using a rather makeshift
light shield from the pull down blind, an in-flight safety leaflet and two sick bags(!), it was
just possible for camera to record the green auroral arc. The photograph below shows that
the arc is plainly visible surrounded by internal window reflections caused by stray light
getting in through the makeshift light shield.
A lot of photographs were taken using this technique and it may be possible to animate some
of them together to make a short 'movie' which shows the dynamic motion of the aurora. I'll
add the movie to this page if it works out.
Despite the fact that the fully illuminated cabin shots suffer from extreme internal reflections,
it is possible to reduce the impact of these unwanted effects using advanced astronomical
image processing techniques. The image below is a first stage attempt to do this...
Is that it?
To see the aurora properly you need to be dark adapted. This typically takes around half an hour
to achieve. Once your eyes have become accustomed to the dark it's amazing how much
additional detail can be seen. It's also much easier to really 'see' the aurora
when standing on the ground and looking up at it. This being the case, as Lapland
on the 9/10 December showed, the problem with ground based observation is simply
the fact that you are at the mercy of the weather!
More Information
Paul Money's website can be found here www.astrospace.co.uk. Here you
can find additional auroral photos and details of Omega's popular Northern Light Flights. These comprise
a pre-flight presentation and a 3 hour flight north in search of the Northern Lights. It's the only
way to beat the clouds and guarantee a clear sky. Auroral visibility is, of course, at the
discretion of Mother Nature! Pau'ls site is the place to go to get his NightScenes book which will
alert you to lots of astronomical events that be happening over 2007, many of which can
be seen from your own back garden!
Auroral activity is reported from www.spaceweather.com,
http://www.dcs.lancs.ac.uk/iono/aurorawatch/
and http://www.sec.noaa.gov/pmap/ amongst others.
For more information regarding the Omega Nothern Light Flights or any of their other
astronomical excursions, their website can be found here http://www.omegaholidays.co.uk.
...And Finally!
It was a great pleasure to meet everyone on the Lapland overnight excursion. I hope you all
had a great stop over in Lapland and will consider another trip up with us in search of those
elusive but so beautiful Northern Lights. Have a great Christmas!
Pete Lawrence