SunCalc

SunCalc is an interactive online tool designed to calculate and visualize the sun's movement and various sunlight phases across the globe. Users can select any location on an interactive map and specify a date and time, or use a "live" mode, to obtain detailed solar data. The application provides essential information such as dawn, sunrise, culmination, sunset, and dusk times, along with daylight duration. It also calculates the sun's altitude, azimuth, and shadow length for objects at a specified height.

Beyond basic sun phases, SunCalc offers advanced astronomical data including Julian Date Ephemeris (JDE), Greenwich Mean Sidereal Time (GMST), Geocentric Hour Angle (GHA), declination, and right ascension. It also provides key dates for equinoxes and solstices. For photovoltaic system planning, the tool delivers crucial metrics like solar constant, air mass, and irradiance, making it valuable for energy-related applications.

The interface includes various base maps like OpenStreetMap and Esri Satellite, allowing users to choose their preferred geographical context. Time and date sliders enable precise control over the simulation, visualizing the sun's path and effects throughout the day and year. This makes SunCalc a versatile resource for architects, photographers, solar energy professionals, and anyone interested in solar geometry.