WFS API

From the dataset abstract

Upward direct or reflected lighting (nW/cm2/sr) at night in the Helsinki metropolitan area. The images were taken in May 2014.

The data was completed in the Decumanus project and it was produced by Eurosense, a Belgian geographic information services company participating in the project, using NOAA satellite images as the source material.

Source: Pääkaupunkiseudun yöllinen valaistus satelliittikuvassa