Hi,
The BAA CfDS and Philip's have got together to produce a dark sky map of Britain and Ireland. It's in the main bookshops in Dublin for around 10 euro apparently.
The map is a similar but more detailed version of the one on the main ILPAC site
irishastronomy.org/ilpac/
. That image is based on the work of scientists at the University of Padova and available from
www.inquinamentoluminoso.it
This map uses the same source for the data from the US Air Force Defence Meterological Satellite Program.
This map is different from the more familiar night time satellite image. While ordinary satellite images just measure the light upwards towards the satellite, this map also considers the light that would shine in all directions and also the light that is scattered in the atmosphere. This information is then converted to show the "naked eye limiting magnitude", and the colour scale on the map indicates the faintest magnitude you can see from a location.
The naked eye limiting magnitude of my home, looking directly upward is about 4.5, and sure enough the map says it should be around 4.5 also so the data seems accurate.
People living in light polluted areas or who would consider driving to even darker skies will be interested in this product. It takes the limiting magnitude map and superimposes it onto the 1:1313750 (1inch 20 miles) philips road map. You will need a more detailed atlas that shows hills, more roads etc. to compliment this map so you can find the best observing site.
Some of you may have seen a recent article in the Irish Times where one astronomer was quoted as saying that you can escape Dublin's light pollution by driving 10 miles from the city. This map shows that the nearest point you can se magnitude 6 stars is about 27 miles from the city into the Wicklow mountains.
The most striking thing to note in the map is that there is practically nowhere in England that you can see magnitude 6 stars, and in the whole of the UK only the mountains in Scotland and Wales provide really dark skies. By contrast most of Ireland can see magnitude 6 stars. Unless we continue to educate and promote better lighting in Ireland we will loose this Trying to reduce light pollution is a lot harder than trying to avoid it in the first place. Want to help? Visit
irishastronomy.org/ilpac/
or
www.darkskies4ni.co.uk/
I will have this map with me for those who want to have a look at it at my lecture to Tullamore Astronomical Society on Monday, and also at the Connaught Star Party later in the month.
Cheers,
~Al
  