Picture of the Week: Aurora
Dark skies have returned to the North of Scotland. This welcome auroral display started off as a green arc, quite close to the horizon, with a purple haze above it. Once it became active there were some nice, bright rays. At 00:34 UT, approx., a second, fainter, green arc formed above the main one. This was short-lived.
This image was taken with a Canon EOS 40D and Sigma EX 24-60mm lens; 30 Second exposures @ f/3.2, ISO-800.
Observer: Alan C Tough
Location: Elgin, Scotland; 57 deg 39′N, 3 deg 29′W
Date: 2010 August 04-05
Time: 23:59-01:19 UT
Condition: a
Qualification:
Structure: R2
Form: RA
Brightness: 2
Colour: f
Altitude: maximum height 30 deg.
Azimuth: 320 – 050 deg.
The BAA Aurora Section encourages the observation of the aurora, the recruitment and training of observers, the collection, analysis and reporting on the occurrences of auroral events. The present observer network comprises members of the BAA or other astronomical societies, individual observers, professional meteorologists and ships’ officers at sea. Observations are collected from Canada, the United States, Iceland, The British Isles and European countries. The co-ordination of observing in the Southern Hemisphere is carried out by the Royal New Zealand Astronomical Society Aurora Section. There is very close co-operation between the two Sections and details of observations are exchanged.
Our Section investigates the behaviour of the mid latitude storm aurora as the polar auroral oval expands during active conditions. On the other hand one of our members has spent a number of holidays in January on the island of Spitsbergen to observe and study the polar aurora, the dayside aurora and the theta aurora that can only be observed over the 24 hour sunless Arctic night. The original reports as received from observers are placed in the archives of Aberdeen University, Scotland and the details thereof are the subject of annual reports and technical papers published in the BAA Journal and in the “Marine Observer” as published by the British Meteorological Office.
The Section also observes the noctilucent clouds that are visible in the period May – August in the northern hemisphere, only as a summer phenomenon. The clouds appear at a height of about 80 kilometres and are visible when the sun is between 6 and 16 degrees below the horizon. The techniques to observe the clouds are identical to those used with the aurora hence Section members are well placed to make observations for the assistance of upper atmosphere scientists, who have asked us for our assistance. In this instance there exists a Canadian network of observers. There is also a good network of observers in Finland.
Aurora alerts by text, phone and email are available from Spaceweather.com



@britastro