INTERACTIVE KEYSTROKE COMMANDS ? Print help : Execute colon command spbar Measure object q Exit task COLON COMMANDS :show Show the input and output coordinate systems :isystem [string] Show / set the input coordinate system :osystem [string] Show / set the output coordinate system :ounits [string string] Show / set the output coordinate units :oformat [string string] Show / set the output coordinate format VALID INPUT COORDINATE SYSTEMS image [tv] VALID OUTPUT COORDINATE SYSTEMS image [logical/tv/physical/world] equinox [epoch] noefk4 [equinox [epoch]] fk4 [equinox [epoch]] fk5 [equinox [epoch]] icrs [equinox [epoch]] apparent epoch ecliptic epoch galactic [epoch] supergalactic [epoch] VALID OUTPUT CELESTIAL COORDINATE UNITS AND THEIR DEFAULT FORMATS hours %12.3h degrees %12.2h radians %13.7g