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SIM_sun
The Simulation
SIM_sun is a simulation of the Sun's movement across the sky. Given the location (latitude, longitude) of an observer on the Earth, the timezone (offset from UTC), and a starting local time, this simulation calculates the position of the Sun in the sky over time.
Inputs
| Variable | Type | Units |
|---|---|---|
| sun_predictor.sun.observer_latitude | double | degree |
| sun_predictor.sun.observer_longitude | double | degree |
| sun_predictor.sun.observer_offset_from_UTC | int | hr |
| sun_predictor.sun.local_time | CALENDAR_DATE | -- |
CALENDAR_DATE
| Member | Type | Units |
|---|---|---|
| year | int | -- |
| month | int | -- |
| day | int | day |
| hour | int | hour |
| min | int | min |
| sec | double | s |
Outputs
| Variable | Type | Units |
|---|---|---|
| sun_predictor.sun.JD | double | day |
| sun_predictor.sun.right_ascension | double | degree |
| sun_predictor.sun.declination | double | degree |
| sun_predictor.sun.hour_angle | double | degree |
| sun_predictor.sun.local_sidereal_time | double | s |
| sun_predictor.sun.sidereal_time_at_Greenwich | double | s |
| sun_predictor.sun.solar_azimuth | double | degree |
| sun_predictor.sun.solar_elevation | double | degree |
| sun_predictor.sun.local_time | CALENDAR_DATE | -- |
| sun_predictor.sun.utc | CALENDAR_DATE | -- |
NOTE: 0 <= Solar Azimuth < 360 degrees. North = 0, East = 90, South = 180, West = 270.
Scenarios
RUN_Winter
RUN_Summer
References
Meeus, Jean, (1998) "Astronomical Algorithms", Willmann-Bell, Inc. ISBN 0-943396-61-1.