Amateur astronomers in North America monitor local sky conditions using the Clear Sky Chart (CSC) web sites which provide a very detailed 48 hour color coded observing forecast chart for cloud cover, transparency, seeing and other factors. This iOS app contains a database of more than 6000 forecast locations in Canada, the USA and Mexico and can retrieve new entries.

The summary screen monitors your four or five (on 4 inch or larger retina display) favourite observing locations.  Each square represents one hour and the colors vary from dark blue (excellent) to white (very poor) conditions for observing.  A red line indicates local midnight and there is a last updated timestamp.  Tapping on any preview chart will open a menu of options that allows you to (i) see a more detailed chart/legend, (ii) map the chart location, (iii) open the CSC web page, (iv) select a different chart location to monitor, (v) delete the chart or (vi) share the chart via text, email or social media.

Locations Services can help you find nearby CSC locations when you travel. Refer to Attilla Danko’s excellent CSC web site home page for complete details on interpreting the preview and detailed charts. For more information download the comprehensive PDF User Guide. There is a nominal fee for the app with a portion of every sale helping to sponsor Attilla Danko's Clear Sky Charts sites.

*** New version 2.08 for iOS 13+ approved by Apple is available! ***

Please email any support issues, questions or suggestions for the app to Anything Binary.

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