Astronomical observatories have been measuring the brightness of the sky (NSB) using the methods of astronomical photometry with telescopes, photoelectric photometers and CCD cameras. The observations are disperse and sporadic. This is why some dedicated devices (including all-sky cameras) have been designed to automatically monitor the sky brightness at the observatories.
These sophisticated and expensive instruments are restricted to research groups since they are out of reach for the interested citizens who wish to make a contribution to light pollution research. Most of them are using sky photometers (sky quality meter, SQM) a commercial photometer, designed to measure NSB in a photometric band that mimics the human eye response, that provide reliable data at an affordable budget.
We are designing and building low cost devices to measure night sky brightness that could be widely distributed. The final designs will be calibrated and distributed to the community as open hardware. The researchers and also the interested people could acquire the parts and replicate the photometers from the instructions provided. Among the new features for these photometers we plan to add the capability to automatically send data to a repository located in a server, the autonomous operation with solar panels and batteries in remote places and the ability to measure in different spectral bands.
We also present open source software for NSB research. PySQM, designed for SQM photometers, records the NSB data in the IDA-IAU standard data format and also builds the plots along the night. PyASB analyses all-sky images to determine photometric parameters and to build all-sky NSB maps
AUTHORS/INSTITUTIONS: J. Zamorano, M. Nievas, A. Sánchez de Miguel, C. Tapia, S. Pascual, F. Ocaña, J. Gallego, Universidad Complutense de Madrid, Madrid, SPAIN|C. García, Agrupación Astronómica de Madrid, Madrid, SPAIN