Using the Halphen-Goryachev method [20] we calculated the secular variations of the orbital elements of each asteroid mentioned in Table 1 with allowance for perturbations from six planets (Mercury-Saturn) over one cycle of the variations in the arguments of perihelia (4,000-10,000 yrs). The results of calculations are that all these asteroids (exception 1991 BA) are quadruple-crossers of the Earth's orbit, and, therefore, their hypothetical meteoroid streams might produce four meteor showers each. The smallest NEA (1991 BA) is twice-crosser and might produce two meteor showers. We calculated the theoretical orbital elements, geocentric radiants (the right ascension a and declination 6) and geocentric velocities, solar longitudes and corresponding dates of activity of all meteor showers associated with 17 Taurid Complex asteroids. A computerized search for the predicted showers was carried out in the catalogues published by: Cook [21], Kashcheev et al. [22],

Lebedinets et al. [23], and Sekanina [24,25], This search took into account the closeness in the positions of the theoretical and the observed radiants (the requirement used was Aa= A8=±10°), in velocity values (AVg < ± 5 km/s) and period of activity (At<+15 days) for Ds-h^0.2, where Ds.h is the criterion of Southworth and Hawkins [17], which, in the case under consideration, serves as a measure of the similarity between the theoretical and the observed orbits. With the use of these catalogues, 58 out of the 66 theoretically predicted showers were identified with observed showers. Probably, the other 8 showers also are active, but they are not distinguished yet amongst the sporadic background. The values of Ds-h -criterion showed good agreement between the parameters of theoretically predicted and the observed showers.

Figure 1 represents the theoretical (dots) and observed (crosses) radiants of the meteor showers associated with Taurid Complex asteroids. The theoretical and observed radiants are linked in pairs. The curve delineates the ecliptic. Fig. 1 shows that in most cases theoretical and observed radiants coincide or are close with each other, but in some cases their differences reach 10-12° due to daily motion of the radiant which was not taken into account because the published catalogues often don't contain corresponding data.

At present about 2000 minor meteor showers and associations are detected from optical and radar observations of meteors, but in the overwhelming majority of cases the parent comets of these showers have not been recognized. As shown by the results of the present paper, the lack of parent comets of many meteoroid streams may be explaned not only by different changes of the stream and parent comet's orbits, but also by extinction and transformation of parent comets into asteroid-like bodies.

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