1 day ago · Locate a column of blue blocks. That's when the sky will likely to be clear and dark. A more detailed explanation is here, but the short version is: the clear sky chart predicts hourly …

There are clear sky chart forecasts for over 6100 locations, though the coverage area is limited to Canada, the USA and parts of Mexico and the Caribbean. Locations are typically cities, …

Home of CSOG, the Clear Skies Observing Guides: thousands of deepsky objects, carbon stars and double stars with matching AstroPlanner planfiles & tours 🔭

Dec 22, 2025 · At a glance, it shows when it will be cloudy or clear for the next few days. It's a prediction of when San Antonio, TX, will have good weather for astronomical observing. The …

1 day ago · A color-coded map of the world showing sources and levels of light pollution (man-made light that lights up the night sky and reduces what astronomers can see).

4 days ago · This map shows where astronomy-specific weather forecasts, or "clear sky charts", are available. The colors of the markers indicate amount of light pollution there (colors defined …

Based on a numerical weather model, Clear Sky Charts are perhaps the most accurate and the most usable forecasters of astronomical observing conditions for over 1900 observatories and …