МЕТЕОРИ З МУЛЬТИМОДАЛЬНИМИ КРИВИМИ БЛИСКУ: СПОСТЕРЕЖЕННЯ ТА ЯКІСНІ МОДЕЛІ

Abstract

The problem of TV or video registration of meteors with anomalous light curves, in particular with multimodal and bimodal types is considered. The results of observations of two meteors from Perseid shower, obtained with the help of TV systems of super-isocon type are presented. The initial velocities of meteors were typical for Perseid shower meteors: 62.4 km/s and 58.4 km/s. One of the meteors has a light curve of a multimodal character, which can be explained by the fragmentation of the body. Another light curve has an evident bimodal type, which has no final explanation for the present. In opposite to most of registered for the moment meteors with bimodal light curves the given meteor from Perseid shower demonstrates the first peak of illumination to be much more intensive, and the second one to be significantly lower. The maximal brightness in the first peak was +2 magnitude, in the second one +3.5 magnitude, and in depression +4.5 magnitude which almost corresponds to the sky background, while the sensitivity of our observational instruments was +5.5 magnitude; but nevertheless the entire radiation disappearance was not happen. The qualitative models for interpretation of the meteor with bimodal light curve are proposed. One of them stipulates for different variants of realization of the 2-components composition of a meteoroid, when a body as the matter of fact consists of two particles. One of particles, inner as a rule, is high melting, for example a stone of iron; another one, the cover, is lower melting, for example a mix of dust and ice. Other types of the models use the cases of uniform monolith meteoroid of specific geometric shape. It is also intended that the meteoroid can rotate during its motion dependently on changing body shape or shifting its mass center. The proposed models are the simplest in accordance with the number of varying parameters, and can therefore pretend to their reality after successful application of quantitative analysis and according numerical modeling. It is noted that the final confirmation or abolishment of the model type will be possible after carrying out parallel spectral observations of meteors.