"airbursts / bolides of non terrestrial origin" - That would seem to be meteors or other non terrestrial event. I will bet you however the non-classified 1961 paper dealt with shock waves from nuclear explosions. The question being for aircraft designers, how can the B-52, B-58, F-105 and the British Vulcan escape a low or even high level blast. How far do the blast / shock waves from the weapon travel and what are the anticipated safe operational envelope for deploying various nuclear weapons from an aircraft.