The passive satellite will not carry any communications or propulsion systems.

Minitrack could not detect or track an uncooperative or passive satellite.

(See also List of passive satellites)

A passive satellite, it is a sphere of aluminium covered with retroreflectors to reflect laser ranging beams emitted from ground stations on Earth.

These three sources will also roughly distinquish the viewing geometry of passive satellite instruments: an occultation instrument tracks the sun, moon or a star through the limb of the atmosphere, a limb-sounder also looks at the limb but measures scattered radiation while a nadir-looking instrument looks down through the atmosphere at the surface.