23857122-0457-180273-0373

MTMMOT, QAM TID RTMENT Mt COMMER E ED SO es” FATES DEAR MEN OF us MVERCE wre, (PTT DD TDIA ATT Ve Co BU KAU () Re po rt Laocen aor ott asc information on "Ball Lig *htning" oe oe ers Rt te na A A NRRL NEN I CLS 5 Gh ORO Various theories and suggestions have been proposed to explain ball lightning, most of them being without well-established physical foun- dation, inere - still doubt in scientific circles regarding the 1 > orizin of a number of reported cases of ball lightning. Briefl, the explanations of the origin of ball lightning may be broken down as follows; ‘ 7) 2 ‘ f \ pe ag oe 1. : gees Ty ne ae + i (1) Brush discharge (St. Eimo's fire). (May be stationary over sharp-pointed objects, or 4, moving along or near the surface of wires, roofs, rocks, etc., especially on mountains. Conditions most aldalantng for brush discharge occur during thunderstorms, but the phenomenon may occur even & ' dur ins c lear, ‘ary, dusty weather. iwhen a lightning stroke is apvroaching an object, the brush discharge becomes especially intense.) (2) Intensely ionized, incandescent volume of air forme ing end of lightning stroke and lasting for short interval of time. This would ocour mainly during thunderstorms fol- lowing the passage of a lightning stroke. at the ground end, the terminal flash is intense, and vapors, smoke or molten material from objects fused at points struck may enhance and extend the duration of incan- descence., After-inagze formed on the retinas of the eyes of a person looking at the brilliant flash at the point of discharge may give spurious effects.) on (3) Brush discharge in air containing high concentration f' dust or other aerosols, during thunderstorms. If this occurs, it probably is associated with the path taken by a real lightning stroke, and presumably involves corona discharges from suspended particles Gy and possibly combustion in some cases.) om CO 6 Declassification Authority: NND 57565