Geographic basemap
OpenFreeMap vector tiles + OpenStreetMap provide geographic context for coordinate exploration.
Map overview
Explore the map
Search for a place and explore the area. The map also shows a 2022 satellite view of lights at night. It is not a measurement of local sky darkness.
About the map data
It displays EOG VIIRS VNL v2.2 (2022) annual satellite radiance in nW/cm²/sr. The local source and published archive each match their recorded SHA-256 checksums, but the full tile transformation has not been independently rebuilt. This is not a direct measure of local sky brightness or atmospheric pollution, Bortle, or SQM data.
Decision first
Tonight separates forecast inputs, observations and unavailable values.
2022 annual satellite radiance
The dashboard can display the EOG 2022 annual satellite-radiance archive when configured. Its input and published archive each match their recorded hashes, but the full tile transformation has not been independently rebuilt. It is not a direct measure of local sky brightness or atmospheric pollution, Bortle, or SQM data.
Source boundaries
The interface labels live deliveries, forecasts, models and editorial guidance separately.
Free planning
Check tonight before you choose a place
Start with the free Tonight check for forecast context, then use the dashboard to explore locations and coordinates. The provisional 2022 radiance candidate is configured there; its source-to-tile lineage remains under review. Do not treat it as a validated measure of pollution, local sky brightness, Bortle, or SQM.