Meteor Patrol

a system of several photographic units used for the observation of meteors. Each unit generally consists of four to six wide-angle cameras, placed such that the largest possible area of the sky is covered.

For example, the meteor patrol of the Institute of Astrophysics of the Academy of Sciences of the Tadzhik SSR consists of four units, each with six cameras (diameter of the objective D = 10 cm, focal length F= 25 cm) that cover the area of the sky from the zenith to the zenith distance of 50°-55° in all directions. There are three units at the principal observation point. One is parallactically mounted, allowing point images of stars to be obtained. A double-bladed shutter is fitted in front of the objectives of the second unit; the shutter rotates at 1,500 rpm and interrupts the meteor’s trail on the photographic plate. In front of the objectives of the third unit are placed prisms with a refractive angle of 25° for photographing the meteor’s spectrum. The fourth unit is located at a distance of 34 km from the first three.

The joint processing of the photographs of a meteor taken by all the units permits determination of the meteor’s moment of transit, height (with an accuracy of ± 100 m), velocity (with an accuracy of 0.4 percent), radiant (with an accuracy up to 3’), mass, and chemical composition. In order to obtain the largest number of photographs, the patroling of the sky is carried out continuously throughout the entire night, with crew changes every 0.5–1 hr.