3 ms·
Nice project! A few questions: How is this data collected? (I'm guessing a satellite image of city lights across the world) I'm trying to understand the scale
by tppiotrowski 6y ago
Nice project! A few questions:
How is this data collected? (I'm guessing a satellite image of city lights across the world)
I'm trying to understand the scale. Zenith means overhead, so overhead sky brightness. The magnitude scale stops at 17 but I thought magnitudes above 7 is no longer visible to the human eye [1]
[1] https://en.wikipedia.org/wiki/Apparent_magnitude https://en.wikipedia.org/wiki/Apparent_magnitude
- bttrfl 6y agothis is explained in the FAQ. They merge different sources, notably data from SQMs which "stands for Sky Quality Meter. It's a small device that can measure sky quality ie. darkness. It's widely used by amateur astronomers because it's fairly cheap and gives you fast results which can be easily compared to other SQM users." https://www.lightpollutionmap.info/help.html https://www.lightpollutionmap.info/help.html
- deleted 6y ago[deleted]