Prime Keys are:
	obsdate is slotted 'ts_eq' using obsdate_index
DB Index Keys are same as Prime Keys
All Keywords for series iris.orbit_vectors:
	obsdate   	(time)	[OBS_DATE] Date of prediction
	obsdate_epoch	(time)	MDI epoch - adjusted by 30 seconds to center slots on minutes
	obsdate_step	(time)	Slots are 60 seconds wide
	date      	(time)	[DATE] Date of product-file ingestion; ISO 8601
	datestr   	(string)	Human-readable date of product-file ingestion
	rsunobs   	(float)	[RSUN_OBS] The solar radius
	obsvr     	(float)	[OBS_VR] The velocity of the Sun with respect to IRIS
	dsunobs   	(double)	[DSUN_OBS] IRIS-Sun distance
	heixobs   	(double)	[HEIX_OBS] IRIS-Sun x position (ECI)
	heiyobs   	(double)	[HEIY_OBS] IRIS-Sun y position (ECI)
	heizobs   	(double)	[HEIZ_OBS] IRIS-Sun z position (ECI)
	geixobs   	(double)	[GEIX_OBS] IRIS x position (ECI)
	geiyobs   	(double)	[GEIY_OBS] IRIS y position (ECI)
	geizobs   	(double)	[GEIZ_OBS] IRIS z position (ECI)
	source    	(string)	Record query to identify source file containing orbit data