In this work, genetic connections (GC) of the small meteor shower rho-Geminids with near-Earth objects (NEOs) of the Apollo group were studied using the author's multiparameter method. The multiparameter method for determining GC of meteor showers with probable parent bodies is based on the use of a set of criteria for identifying orbits, such as: D-criterion by Drummond, Kholshevnikov's metric, Tisserand's parameter, mu and. quasistationary parameters of the restricted three-body problem, longitude of perihelion p of meteor orbit. The method of identifying meteoroids with asteroids involves computational procedures and the calculation of critical values for each of the criteria used, which increases the reliability of finding the GC for the objects under study. The catalogues of meteor orbits: Meteoroid Orbit Database v3.0, CAMS and EDMOND 5 v.04 of the European Meteor Network were used as source material in the work.

In studying the connections of the δ-Cancrids (DCA) meteor stream, consisting of the northern (NCC) and southern (SCC) branches, with the comet–asteroid complex, the structure of the shower was studied using visual and television observations. According to visual observations, it was found that for meteors with a minimum recorded stellar magnitude of +3m and brighter, the maximum of activity ZHR = 8.6 ± 1.8 is observed at the Sun’s longitude 298.5° ± 1.2°, while the parameter r of the luminosity function during the period of the shower activity varies in the range of 1.5–2.0. For meteors weaker than +3m, the moment of maximum occurs 1.4° later than for brighter meteors. For the orbits of meteors of the NCC and SCC branches, obtained from television observations, the dependence of the values of the semimajor axes and eccentricities on the mass of meteoroids was also revealed. The orbit separation time for the δ-Cancrid meteors in the meteor magnitude range from 0m to +3m due to the nongravitational Poynting–Robertson effect is 22–26 thousand years for the southern branch SCC, and 24–29 thousand years for the northern branch NCC.

Asteroids and comets are the oldest objects in the Solar System and contain the initial matter that existed at the moment of its formation. By studying those small celestial bodies one may describe the processes taking place at the early stages and conditions of the formation of the Solar System. The study of the genetic relationships (using metrics based on orbital elements) of meteor showers with parent bodies (asteroids and comets) can be used to develop the theory of evolutionary processes that took place at the time of the formation of the solar system. In this work, we have studied the genetic relationships of the small meteor shower of the h-Virginids (HVI) with the near-Earth asteroids of the Apollo group. An author’s multi-factor method is applied, which implies the use of D-criterion by Drummond, metric by Kholshevnikov, Tisserand’s parameter, μ and ν quasi-stationary parameters of the restricted three-body problem, and the analysis of the orbit’s perihelion longitude π. The observational base includes television catalogues meteor orbits that are in the public domain: Meteoroid Orbit Database v2.0 (2010–2012) (CAMS) and the European meteor network EDMOND (2001–2016) catalogues. As a result of this study, the orbit of the h-Virginids (HVI), according to the values of Tisserand’s parameter, was found to be transitional, and thus, it was impossible to identify whether it was of cometary or of asteroid type. Using the author’s method, the asteroids 2001SZ269 and 2014HD19 were distinguished. The 2001SZ269 asteroid was distinguished as a candidate having a possible connection with the h-Virginids’ parent body.

The results of the search for Apollo, Amor, and Aten asteroids with the orbits close to those of meteoroids of the δ-Cancrids meteor complex (code DCA), which consists of the northern (code NCC) and southern (code SCC) branches, are presented. The search for small bodies in close orbits was performed on the basis of a multifactorial method of combining several criteria: Drummond orbital similarity criterion, Kholshevnikov metric, and parameters of the dynamic evolution of the orbits using two catalogs of meteor orbits (Japan Meteor Society, SonatoCo, and CAMS Meteoroid Orbit Database v2.0, CAMS) obtained from television observations. Asteroids in close orbits with the meteoroid orbits of the northern NCC and southern SCC branches of the δ-Cancrids are identified only in the Apollo group. The following asteroids are common for the NCC and SCC branches: 2015 PU228, 2014 YQ34, 2017 YO4 (according to the CAMS orbit catalog); Hephaistos 1978 SB, 2003 RW11, 2006 BF56, 2011 SR12, 2014 RS17, 2001 YB5 (SonatoCo catalog). The asteroid 85182 (1991 AQ) is identified only with the northern NCC branch but in two catalogs of meteor orbits.

This study is focused on the relationships between the κ-Cygnid meteor shower and different groups of asteroids crossing the Earth’s orbit (the so-called near-Earth objects (NEOs)). The analysis is based on the visible structure of the meteor shower and a comprehensive strategy for estimating the proximity of orbits of two bodies. The κ-Cygnid meteor shower (abbreviated as KCG) is observed from August 3 to August 25 every year; it is classified as a minor shower, and the size of its mean orbit is around 3.2 AU, while the geocentric velocity is 20.9 km/s. No parent body (PB) of the shower has been found among comets so far. Relationships between the shower and asteroids, as potential PBs of the shower, are under active examination; some hypotheses on this subject can be found on the website of the Meteor Data Center (MDC) of the International Astronomical Union (IAU).

In this work, the physical parameters of near-Earth objects (NEO), i.e. small celestial bodies crossing the Earth’s orbit, are investigated. First of all, the study of NEO, whose number exceeds 15 thousand, is important in terms of asteroid threats. NEO are mainly stony and iron, but also could be comet nuclei that had lost the icy component under the influence of solar radiation. As a result of analyzing 14800 near-Earth asteroids from the Apollo group, in this work near-Earth objects closely genetically related to the existing meteor showers are determined. 2002LV and 2001MG1 asteroids are the closest to the Kappa-Cygnids by orbital elements. 2014RS17, 2006BF56, 2001YB5 asteroids are the closest to the Delta-Cancrids by orbital elements. 2008VL14, 2006UF17, 2010VF, 2000DO1, 2010CF55, 2010TN55, 2007EJ88, 481482 2007CA19 asteroids are the closest to the Virginids by orbital elements. The D-criterion method was used in the analysis.

Results of BV R observations of meteors in the Perseid, Taurid, Orionid, Geminid, and Lyrid showers, as well as sporadic meteors, carried out with the Mini-MegaTORTORA system are presented. Two-color diagrams for the brightness maxima are constructed. It is shown that meteors in the Perseid, Taurid, and Geminid showers form clusters in the two-color diagrams. Variations in color with a temporal resolution of 0.1 s are considered for some meteors.

Acknowledgements The work is performed according to the Russian Government Program of Competitive Growth of Kazan Federal University. This work was partially supported by scholarship of the President of the Russian Federation to young scientists and post-graduate students number CΠ-3225.2018.3. This work was partially supported by the Russian Foundation for Basic Research, grant no. 1832-00895 mol_a (according to the grant, the method was created and numerical calculations were carried out) and the Foundation for the Advancement of Theoretical Physics and Mathematics “BASIS”. Introduction The Delta Cancrids (DCA) relates to unconfirmed small meteor showers, has 2 branches – the Northern (NCC) and the Southern (SCC) Delta Cancrids, and is observed between January, 1 and January, 31. According to IAU, the Northern Delta Cancrids (NCC) is allegedly related to the 1991 AQ? asteroid, while the Southern Delta Cancrids is related to 2001 YB5? (the symbol “?” indicates the status of hypothesis, date of the application is August 18, 2018). The purpose of the paper is to study the activity of the poorly investigated Delta Cancrids and to search for close orbits among NEOs.

Using the video catalogues of the Perseids, Ursids, and Lyrids meteor showers having genetic connections with comets, the Geminids, Alpha Capricorni, and Taurids having genetic connections with asteroids, and the Kappa Cygnids and Delta Cancrids of unknown origin, the objects with magnitude higher than +3 were studied. The analysis of coordinates of the meteor showers' radiant distribution in relation to their magnitudes showed that the Lyrids has the smallest ellipse of the spread of the radiant positions, with 4 degrees by 8 degrees; for the k-Cygnids the deviation is the greatest, with 28 degrees by 28 degrees; for the other showers, it is between 7 degrees and 10 degrees. The main attention is paid to the determination of structural parameters of the Lyrids meteor shower.