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For observational services, these two parameters provide the corresponding distance to the target at time of observation (in au). When the target is the Sun or Earth, use the target_distance_min/max parameters to provide the distance to the observer.
subsolar_longitude
subsolar_latitude
Provide coordinates of sub-solar point, e.g., especially for disk images. No min/max values.
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subobserver_longitude (min/max)
subobserver_latitude (min/max)
Provide coordinates of sub-observer point, in particular sub-Earth point (disk center) for ground-based observations. No min/max values are back, required for long exposures related to time series, especially on giant planets to test planet attitude.
subsolar_longitude (min/max)
subsolar_latitude (min/max)
Provide coordinates of sub-solar point, e.g., especially for disk images. min/max values are back, also required for long exposures related to time series.
ra
dec
If fixed sky coordinates of the target are provided in the view in addition to standard coordinates, they must be stored in parameters named ra and dec (no min/max variations to maintain compatibility with existing software). This may document the location of a planet in a celestial image, while the main coordinates c1/c2 are used to describe the observed area as longitude and latitude. ICRS coordinate system is assumed; right ascension is provided in degrees (similar to ObsCore). RA, DEC parameters are interpreted correctly by most VO tools.
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