A selected place, not a generic time zone.
SOLAR uses the coordinates and IANA time zone of the place you select. You may choose a one-time current location or search for another place. The same resolved location feeds every solar calculation.
A real instant.
The calculation begins with an actual UTC instant. From that instant and place, SOLAR resolves the Sun, sunrise, solar noon, sunset, twilight and the values used by its time systems.
Several clocks, one Sun.
Changing between Solar Time, Seasonal Hours, Byzantine Time and Local Time does not move the Sun or alter the day. It changes only how the same instant is read.
Clear sky, not weather.
The Physical Sky represents a clear-sky atmospheric state driven by solar geometry. It does not predict local clouds, rain, haze or weather. A beautiful clear-sky model and a weather forecast answer different questions.
Continuous twilight.
Civil, nautical and astronomical twilight are useful names for ranges of solar elevation. They are not hard visual switches. The light should fade continuously through those boundaries as the Sun moves farther below the horizon.
The Halo is temporal.
The Halo arc shows progress between the current pair of horizon events: sunrise to sunset during the day, and sunset to sunrise during the night. It is an understandable temporal instrument, not a literal camera projection of the celestial path.
Local first.
The current product direction performs core solar calculations on the device and stores the selected place and preferences locally. No account is required.