TAB M:

Optical, magnetic and acoustic devices and instruments have recorded or have been affected by the presence of UFOs. Optical devices include simple cameras, movie cameras, cinetheodolites, videocameras and even cameras fitted with diffraction gratings. Magnetic sensors include simple compasses and magnetometers. Acoustic sensors (microphones) have, occasionally, detected sounds associated with the presence of UFOs, although most often no sound is heard. In 1947 a witness reported that his compass rotated as several flying saucers passed overhead. Years later another witness noticed that a saucer seen in the daytime near the horizon appeared to have dark rings around it when viewed through polarized glasses, but not when viewed directly, possibly a result of Faraday rotation in the atmosphere caused by an extremely large magnetic field. A scientist working for the French National Space Agency in the early 1970's determined that there was a inverse relationship between the vertical component of the geomagnetic field measured at field stations scattered throughout France and distance to a reported UFO. Self-propelled machines such as automobiles have been affected in the presence of UFOs. One incident involved two combines operating in a field of grain at night. During the passage of a glowing UFO the gasoline powered combine stopped, whereas a diesel type continued to operate. In April, 1949 at the White Sands proving ground high flying (estimate 150,000 ft) UFOs were tracked and filmed with cinetheodolite cameras. The size was estimated from the image size and the triangulated altitude to be about 30 ft. Electronic devices have been affected, including gyrocompasses (TAB H - Mansfield, Ohio, 1973; the gyrocompass had to be repaired after the incident) and radios (TAB H - Tehran, Iran, 1976; Kirtland AFB, 1980). Plants have been affected by UFOs. An incident in 1980 in France was investigated by GEPAN (see TAB J). The GEPAN report shows that after a circular UFO landed on a lawn (as reported by the witness) the chlorophyll in the grass was affected by an amount which diminished as 1/r where r is the distance from the center of the landing spot. Plant scientists could not explain how the chlorophyll change had been caused.