@spiceErrorCheck<EOL>def clight():
return libspice.clight_c()<EOL>
Return the speed of light in a vacuum (IAU official value, in km/sec).

http://naif.jpl.nasa.gov/pub/naif/toolkit_docs/C/cspice/clight_c.html

:return: The function returns the speed of light in vacuum (km/sec).
:rtype: float