Sky direction

A union of the various standard sky direction representations supported by SKA, as defined in ADR-63.

https://schema.skao.int/ska-skydirection/1.0
anyOf	ICRS sky direction 1.0
	A sky direction defined in the ICRS reference frame.
	type	object
	properties
	target_name	A name for the target. If reference_frame is ‘special’ or ‘tle’ then the name might be of a solar system body or a satellite in Earth orbit.
		type	string
	reference_frame	Must be “icrs” for a sky direction defined in the ICRS reference frame. Validation is case-insensitive.
		type	string
	attrs	1.0*
		Attributes for an ICRS sky direction
		type	object
		properties
		c1	The longitude coordinate, specifying degrees right ascension in the ICRS reference frame. Value must be in the range 0 <= c1 < 360.
			type	number
		c2	The latitude coordinate, specifying degrees declination in the ICRS reference frame. Value must be in the range -90 <= c2 <= 90.
			type	number
		pm_c1	Longitudinal proper motion of target, measured in arcseconds per year.
			type	number
		pm_c2	Latitudinal proper motion of target, measured in arcseconds per year.
			type	number
		epoch	Epoch of proper motion, giving the date when the proper motion offset was zero.
			type	number
		parallax	The parallax in seconds of arc.
			type	number
		radial_velocity	Radial velocity along the line of sight in m/s.
			type	number
		additionalProperties	True
	additionalProperties	True
	AltAz sky direction 1.0
	A sky direction defined in the AltAz reference frame
	type	object
	properties
	target_name	A name for the target. If reference_frame is ‘special’ or ‘tle’ then the name might be of a solar system body or a satellite in Earth orbit.
		type	string
	reference_frame	Fixed as “altaz” for a sky direction defined in the AltAz reference frame. Validation is case-insensitive.
		type	string
	attrs	1.0*
		Allowed attributes for an AltAz sky direction
		type	object
		properties
		c1	The azimuth coordinate in degrees. Value must be in the range 0 <= c1 < 360.
			type	number
		c2	The elevation coordinate in degrees. Value must be in the range 0 <= c2 <= 90.
			type	number
		additionalProperties	True
	additionalProperties	True
	Galactic sky direction 1.0
	A sky direction defined in the Galactic reference frame.
	type	object
	properties
	target_name	A name for the target. If reference_frame is ‘special’ or ‘tle’ then the name might be of a solar system body or a satellite in Earth orbit.
		type	string
	reference_frame	Must be “galactic” for a sky direction defined in the Galactic reference frame. Validation is case-insensitive.
		type	string
	attrs	1.0*
		Attributes for a Galactic sky direction
		type	object
		properties
		c1	The longitude coordinate, specifying degrees right ascension in the Galactic reference frame. Value must be in the range 0 <= c1 < 360.
			type	number
		c2	The latitude coordinate, specifying degrees declination in the Galactic reference frame. Value must be in the range -90 <= c2 <= 90.
			type	number
		pm_c1	Longitudinal proper motion of target, measured in arcseconds per year.
			type	number
pm_c2		Latitudinal proper motion of target, measured in arcseconds per year.
		type	number
epoch		Epoch of proper motion, giving the date when the proper motion offset was zero.
		type	number
parallax		The parallax in seconds of arc.
		type	number
radial_velocity		Radial velocity along the line of sight in m/s.
		type	number
additionalProperties		True
additionalProperties	True
Special sky direction 1.0
A sky direction whose coordinates are defined in Katpoint.
type	object
properties
target_name	A name for the target. This should be the name of a resolvable entity in Katpoint, for example, the name of a solar system body.
	type	string
reference_frame	Must be “special” for a catalogue sky direction. Validation is case-insensitive.
	type	string
additionalProperties	True
Two-Line Element sky direction 1.0
A sky direction defined by a Two-Line Element (TLE) set.
type	object
properties
target_name	A name for the target. For a TLE sky direction, this could be the name of a satellite in orbit.
	type	string
reference_frame	Must be “tle” for a sky direction defined in the TLE reference frame. Validation is case-insensitive.
	type	string
attrs	1.0*
	Attributes for a TLE sky direction.
	type	object
	properties
	line1	First line of a two-line element (TLE) sky direction.
		type	string
	line2	Second line of a two-line element (TLE) sky direction.
		type	string
	additionalProperties	True
additionalProperties	True