Bulk and grain density, porosity, and magnetic susceptibility of 67 individuals of Košice H chondrite fall were measured. The mean bulk and grain densities were determined to be 3.43 g/cm 3 with standard deviation (s.d.) of 0.11 g/cm 3 and 3.79 g/cm 3 with s.d. 0.07 g/cm 3 , respectively. Porosity is in the range from 4.2 to 16.1%. The logarithm of the apparent magnetic susceptibility (in 10 −9 m 3 /kg) shows narrow distribution from 5.17 to 5.49 with mean value at 5.35 with s.d. 0.08.These results indicate that all studied Košice meteorites are of the same composition down to ∼g scale without presence of foreign (non-H) clasts and are similar to other H chondrites. Košice is thus a homogeneous meteorite fall derived from a homogeneous meteoroid.

Aims. The complex dynamics of bodies, originating from the interplanetary matter and passing through Earth’s atmosphere, defines their further position, velocity, and final location on Earth’s surface in the form of meteorites. One of the important factors that affect the movement of a body in the atmosphere is its shape and orientation. Our goal is to model the interaction of real shape meteoroids with Earth’s atmosphere and compare the results with the standard spherical body approach. Methods. In the simulation, we use 3D models of fragments of the Košice meteorite with different sizes and shapes. Using a 3D model of fragments, we consider the real shape of the body to define its resistance properties during atmospheric transition more specifically. The simulation is performed using virtual wind tunnel in the MicroCFD (Computational Fluid Dynamics) software to obtain more realistic drag coefficients and using the µ(m)-Trajectory software to model the particle trajectory in the atmosphere including the wind profile. The final outputs from these programs are the drag coefficient as a function of the altitude and the particle orientation. Using these parameters we get the more realistic body trajectory and the impact area coordinates. Comparison of the results for real and spherical model meteorite impact location is discussed. Results. Simulation showed significant differences in trajectory and the impact area for the different real body orientations compared to the spherically symmetric body. Also, an important result is a difference in the impact area of the real body with a specific orientation without rotation and the body with considered rotation. The significant difference between the modeled impact of a real shape body and its real place of finding compared to a spherically symmetric body indicates the importance of the method used.

<p>            All-sky camera systems such as the AMOS network, record a large number of fireball events. By using multi-station triangulation method obtain information about trajectory of the body in the description change in altitude and velocity over time. Based on the characteristic of the object trajectory can determine important physical properties as the input mass of the meteoroid or the final mass of meteorites, and thus the probability of the formation and impact of particles on the Earth's surface. For this purpose, we used the method of dimensionless coefficients α (ballistic coefficient) and β (mass loss coefficient), which define the impact of the dynamical and physical properties of meteoroids on the searched input/final masses.</p><p>            Large number of recorded fireballs requires automatic data processing and their effective reduction. For this purpose, we have created a program with a user interface that works with data from all-sky fireballs cameras (in our case we focus on data from the Slovak AMOS system), defines the values of α-β coefficients and evaluates the probability of the meteorite formation with specific mass during the flight through the atmosphere. The program gives an interactive settings of physical parameters of the body and thus defines impact on the required values of body input/final masses. This algorithms was created for the purpose of user-friendly processing of scientific data, and the same time serves for the selecting suitable candidates for the formation and impact of dust particles and meteorites on the Earth's surface.</p>