baroAltitude: The barometric altitude as reported by the aircraft transponder and with reference to the pressure level of 1013.25hPa. This is measured in meters.
groundSpeed: The ground speed as calculated by a satellite positioning system. This is measured in meters/second.
course: The true course of the aircraft as calculated by a satellite positioning system. Be aware that this is accurate only when the aircraft is in motion.
verticalRate: The vertical rate of climb or descent of the aircraft as reported by its transponder. The unit of measure is meters/second. Negative values indicate a descent.
onGround: A boolean value that indicates if the aircraft is on the ground or in the air. This information is provided on a best effort basis, as not all type of sources support transmission of this data.
observed: An ISO datetime string that indicates when was this position recorded.
source: The type of source that reported this position. Possible values are ADSB, MLAT, ASDI, OCEA, SATE, HFDL, ASTERIX