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GeoLon - The geodetic longitude of the observer   

Description:
This attribute specifies the geodetic (or equivalently, geocentric) longitude of the observer, in degrees, measured positive eastwards. See also attribute GeoLat. The default value is zero.

The value is stored internally in radians, but is converted to and from a degrees string for access. Some example input formats are: "155:19:23.2", "155 19 23.2", "155:19.387", "155.32311", "E155.32311", "-204.67689", "W204.67689". As indicated, the sign of the longitude can optionally be indicated using characters "E" and "W" in place of the usual "+" and "-". When converting the stored value to a string, the format "[s]ddd:mm:ss.s" is used, when "[s]" is "E" or "W" and the numerical value is chosen to be less than 180 degrees.

Type:
String.

Class Applicability:
SpecFrame
All SpecFrames have this attribute.



next up previous
Next: Grf - Use Grf functions registered through astGrfSet?
Up: AST Attribute Descriptions
Previous: GeoLat - The geodetic latitude of the observer

AST A Library for Handling World Coordinate Systems in Astronomy
Starlink User Note 211
R.F. Warren-Smith & D.S. Berry
30th April 2003
E-mail:ussc@star.rl.ac.uk

Copyright (C) 2003 Central Laboratory of the Research Councils