Natural Resources Wales (NRW) commissioned Land Use Consultants to create the web-based map Dark Skies and Light Pollution in Wales using satellite imagery of Wales taken at 1.30am in a morning.
It revealed more than 68 per cent of the country and 95 per cent of Welsh National Parks and Areas of Outstanding National Beauty fall within the two darkest night sky categories. There are also indications that the amount of light emitted in cities appear to be decreasing too the NRW says.
Powys is one of the best counties for dark skies, away from towns such as Newtown and Welshpool. Lake Vyrnwy is another area where light pollution does not affect star gazing.
The evidence could be used to create new dark sky reserves in Wales, promote the benefits of dark sky friendly lighting and encourage the consideration of light pollution in planning applications and the design of post Covid 19 green recovery developments.
Jill Bullen, Landscapes Lead Specialist Advisor for NRW, said it could also help identify where reducing night light pollution could be particularly beneficial to wildlife and nature networks.
“Dark skies can affect our experience of nature, landscapes and green spaces and can benefit our health and well-being and local wildlife," she said.
“Although dark skies are most often experienced in remote and rural landscapes, our experience of the night sky can be enhanced in towns and settlements by reducing light pollution and using dark sky friendly lighting.
“Lighting kept on for longer than it is needed or units that spill light upwards, rather than to where it is most needed, contribute to sky glow, light intrusion and add to light pollution.
“Many local authorities now have energy saving policies in place that affect lighting and contribute to a lower carbon future.
“Some lights are being dimmed, part night lit or switched off through the night where it is possible and safe to do so, upgrades that include shielding to point light downwards can help to maintain dark skies in Wales."