; (ii) mundane human-made airborne objects, clutter, and marine debris; (iii) Federal, State, and local government, commercial industry, academic, and private sector aerospace platforms; (iv) Federal, State, and local government, commercial industry, academic, and private sector ocean-surface and undersea vehicles; and (v) known foreign systems. (21) Third agency The term third agency means a Government agency that originated a unidentified anomalous phenomena record that is in the possession of another Government agency. (22) Unidentified anomalous phenomena (A) In general The term unidentified anomalous phenomena means any object operating or judged capable of operating in outer-space, the atmosphere, ocean surfaces, or undersea lacking prosaic attribution due to performance characteristics and properties not previously known to be achievable based upon commonly accepted physical principles. Unidentified anomalous phenomena are differentiated from both attributed and temporarily non-attributed objects by one or more of the following observables: (i) Instantaneous acceleration absent apparent inertia. (ii) Hypersonic velocity absent a thermal signature and sonic shockwave. (iii) Transmedium (such as space-to-ground and air-to-undersea) travel. (iv) Positive lift contrary to known aerodynamic principles. (v) Multispectral signature control. (vi) Physical or invasive biological effects to close observers and the environment. (B) Inclusions The term unidentified anomalous phenomena includes what were previously described as— (i) flying discs; (ii) flying saucers; (iii) unidentified aerial phenomena; (iv) unidentified flying objects (UFOs)