Data file used by Starry Night Pro, an application that helps users observe constellations; contains display settings for the view of the sky, constellations, planets, meteor showers, solar system, etc.

To create a default view (which creates the SNO file), select Options → Save Current Options As Default and click Save in the prompt. This action will create a SNO file in the Prefs\[application version] location. To create a preset (which creates the SNO file), select Options → Save Preset..., name the file, choose the save location (the default location is in Sky Data\View Options folder), and click Save. You can also choose a default preset view, which are SNO files that are located in the Sky Data\View Options folder. To choose one of these views, select Options → Presets → [your desired view].