# pvlib.solarposition.ephemeris¶

pvlib.solarposition.ephemeris(time, latitude, longitude, pressure=101325, temperature=12)[source]

Python-native solar position calculator. The accuracy of this code is not guaranteed. Consider using the built-in spa_c code or the PyEphem library.

Parameters
• time (pandas.DatetimeIndex) – Must be localized or UTC will be assumed.

• latitude (float) – Latitude in decimal degrees. Positive north of equator, negative to south.

• longitude (float) – Longitude in decimal degrees. Positive east of prime meridian, negative to west.

• pressure (float or Series, default 101325) – Ambient pressure (Pascals)

• temperature (float or Series, default 12) – Ambient temperature (C)

Returns

DataFrame with the following columns

• apparent_elevation : apparent sun elevation accounting for atmospheric refraction.

• elevation : actual elevation (not accounting for refraction) of the sun in decimal degrees, 0 = on horizon. The complement of the zenith angle.

• azimuth : Azimuth of the sun in decimal degrees East of North. This is the complement of the apparent zenith angle.

• apparent_zenith : apparent sun zenith accounting for atmospheric refraction.

• zenith : Solar zenith angle

• solar_time : Solar time in decimal hours (solar noon is 12.00).

References

1

Grover Hughes’ class and related class materials on Engineering Astronomy at Sandia National Laboratories, 1985.