Description of the source to be observed. Includes coordinates, velocity, name and a set of SourceProperties.
Note: Major solar system bodies will be known by the system and can selected by name. For other moving bodies a SourceEphemeris may be specified: this should probably be its own type, but details are TBC. For now it is a String.

General Info
Name	FieldSource
Owner	schedblock
Visibility	public
Is Active	false
Is Abstract	false

Inner Elements
Name	Type
unnamed	Instance Specification

Relations
Name	Type	Begins	Ends
unnamed	Association	SchedBlock	FieldSource
unnamed	Association	Reference	FieldSource
unnamed	Association	FieldSource	Target
unnamed	Association	FieldPattern	FieldSource
unnamed	Association	SourceProperty	FieldSource
unnamed	Association	FieldSource	QuerySource
unnamed	Association	FieldSource	ObsAttachment

Attributes
Name	Type	Classifier	Default Value
sourceCoordinates	SkyCoordinates	FieldSource
sourceName	String	FieldSource
sourceVelocity	Velocity	FieldSource
sourceEphemeris	String	FieldSource
pMRA	AngularVelocity	FieldSource
pMDec	AngularVelocity	FieldSource
nonSiderealMotion	Boolean	FieldSource	false
solarSystemObject	SolarSystemObjects	FieldSource	Unspecified
parallax	Angle	FieldSource
unnamed	Reference	FieldSource
unnamed	FieldPattern	FieldSource
unnamed	SchedBlock	FieldSource
name	String	FieldSource
isQuery	Boolean	FieldSource	false
unnamed	QuerySource	FieldSource
ephemerisFileName	String	FieldSource
Image	ObsAttachment	FieldSource