Best Dark Sky Sites Near Portland (2016)
Purpose
To show dark sky locations near Portland suitable for astronomical observation, including six featured areas. Intended for amateur astronomers and the general public.
Methodology
GIS overlay analysis was used to find locations meeting several criteria including low light pollution, solid and flat terrain, no canopy cover, and on public land within 500 feet of a public road. Methods included buffer analysis, aspect, and raster overlay. Several USGS DEMs were combined using a mosaic dataset and the light pollution layer was created using NASA's Earth at Night composite satellite image. Cartographic techniques include a dark theme to suggest night time with an orange glow for the light pollution layer.
Specifications
8.5 x 11 inches, color.
Purpose
To show dark sky locations near Portland suitable for astronomical observation, including six featured areas. Intended for amateur astronomers and the general public.
Methodology
GIS overlay analysis was used to find locations meeting several criteria including low light pollution, solid and flat terrain, no canopy cover, and on public land within 500 feet of a public road. Methods included buffer analysis, aspect, and raster overlay. Several USGS DEMs were combined using a mosaic dataset and the light pollution layer was created using NASA's Earth at Night composite satellite image. Cartographic techniques include a dark theme to suggest night time with an orange glow for the light pollution layer.
Specifications
8.5 x 11 inches, color.