urn:nasa:pds:a15sws_solar_wind_28s_1hr:document:a15_solar_ephemeris 1.0 1.23.0.0 Product_Document 2025 The Solar Ephemeris file provides the local position of the Sun at the site of the Apollo 15 SWS instrument (3.63 East Longitude, 26.13 North Latitude). The ephemeris data were calculated at hourly intervals, beginning at 1971-Jul-30 00:00 and ending at 1972-Jul-01 00:00 Universal Time Coordinated (UTC). The columns are: - Date (yyy-mmm-dd) in UTC, - Time in hours:minutes in UTC, - Apparent solar azimuth angle in degrees (north=0, east=90), - Apparent solar elevation angle in degrees with respect to a plane perpendicular to the local zenith where a negative sign means the Sun is below the plane horizon and 90 degrees is vertical, - Change in solar azimuth with time multiplied by the cosine of the elevation in arcseconds per minute, and - Change in solar elevation with time in arcseconds per minute. Local topography is not taken into account, typically the local sunrise and sunset will be offset by a few hours from the zero solar elevation values because of surrounding landforms. The table was generated by the Horizons On-Line Ephemeris System at the Jet Propulsion Laboratory (http://ssd.jpl.nasa.gov/). 2025-09-26 1.0 Initial version. 1971-07-30T00:00:00Z 1972-07-01T00:00:00Z Apollo 15 Mission urn:nasa:pds:context:investigation:mission.apollo_15 document_to_investigation The Apollo 15 Lunar Surface Experiments Package Host urn:nasa:pds:context:instrument_host:spacecraft.a15a is_instrument_host Apollo 15 Lunar Surface Experiments Package Solar Wind Spectrometer Instrument urn:nasa:pds:context:instrument:sws.a15a is_instrument Moon Satellite urn:nasa:pds:context:target:satellite.earth.moon document_to_target 2008-07-24 7-Bit ASCII Text version English 1 a15_solar_ephemeris.asc 7-Bit ASCII Text