Galician Night Sky Brightness Monitoring Network

The Network


The Galician Night Sky Brightness Monitoring Network is the result of a joint collaboration between MeteoGalicia, the Galician public meteorological agency, and the Photonics4Life research group at Universidade de Santiago de Compostela (USC).

      Its aim is to provide long-term and real-time data on the evolution of the brightness of our night skies in order to better understand the dynamics of our nighttime environment and help addressing the causes and consequences of light pollution.

      It is based on low-cost SQM-LR luminance meters integrated in several of the automatic weather stations belonging to MeteoGalicia. Researchers and the public at large can access in real time the sky brightness measurements and relevant meteorological variables.

     Fourteen measurement sites have been selected for the first phase of deployment of this Network, all of which (Santiago de Compostela, Lardeira, O Cebreiro, Areeiro, Guísamo, the harbour of Vigo, Fontaneira, Cabeza de Manzaneda, Xares, Paramos, Labrada, Illas Cíes, Illa de Ons and Illa de Sálvora) are already fully operative and online at the time of writing. Click on the image to see map.

     Once completed, the Network covers a wide range of environments: urban, suburban and rural areas, from strongly light polluted city centers to natural parks with pristine dark skies, and from coastal regions to the Galician Eastern Mountain ranges.


Accessing the data

     According to the public service mission of both MeteoGalicia and the USC, the acquired data are available in open access.

     Ten-minute averages of the brightness readings are computed and displayed at the Meteogalicia website. Data streams of the last few days can be seen as a graphic plots. A calibration offset of -0.1 mag/arcsec2 is applied to these readings before displaying them, in order to account for the transmittance of the detector housing glass window. Extended period datasets can be downloaded in different file formats together with the meteorological variables of interest. 

     Data can be accessed from the MeteoGalicia website:    You may also access them from the station list located below.

     One-minute sampling rate datasets with detailed calibration factors for each detector are freely available for researchers and the interested public upon request.


 Active stations

 Santiago de Compostela Data download
 Lardeira Data download
 O Cebreiro Data download
Areeiro Data download
Guísamo Data download
Porto de Vigo Data download
Fontaneira Data download
Cabeza de Manzaneda Data Download
Xares Data Download
Paramos Data Download
Labrada Data Download
Illas Cíes Data Download
Illa de Ons Data Download
Illa de Sálvora Data Download















 Reports (also available at the MeteoGalicia website)

2017 GNSBMN Report (Galician/Spanish/English)

2016 GNSBMN Report (Galician/Spanish/English)

- 2015 GNSBMN Report  (Galician)

- 2014 GNSBMN Report  (Galician)



 Disclaimer: These data may undergo different validation procedures as time goes by, and hence they may be modified. Neither MeteoGalicia nor the USC can be held liable for the different uses or interpretations that the user may make of these data.

 Cláusula de responsabilidade no uso dos datos: Os datos aquí amosados son sometidos a distintas rutinas de validación sucesivas ao longo do tempo, polo que poden darse modificacións dos mesmos. Nin MeteoGalicia nin a USC asumen responsabilidade algunha sobre as diversas utilizacións ou interpretacións que o usuario poida facer dos datos subministrados.