Speaker
Description
Keywords: NEOs, NEAs, Near Earth Space
Decameter size NEAs are of particular interest in the context of the NEO problem because the frequency of collisions with such bodies is much higher than that of larger bodies and the consequences of collisions can be still significant. So far, the population of decameter bodies has been poorly studied since they are difficult to observe. To build an efficient system for detecting and monitoring such bodies it is necessary to estimate their distribution in near-Earth space (NES). We present the results of statistical modeling of NEA entries into NES which is a sphere with a radius of 0.01 au around the Earth.
We considered the dynamic evolution of the NEAs over some dozens of typical periods of the NEAs, fixing every entry into the NES. The NEA population was modeled using the NEOMOD package and integrated for 100 years using the REBOUND package.
The main results are: 1) the frequency of entries of NEAs larger than 10 m is approximately 1000 per year (as lower limit); 2) up to half of the NEAs enter the NES from day-time-hemisphere; 3) there is anisotropy in the flux density of incoming asteroids. 4) typical velocity of approach to the Earth at the distance of 0.01 au is approximately 7.5 km/s (maximum speed can reach up to 30 km/s). 5) the anisotropy decreases when considering a near-Earth sphere of a smaller size. For the Earth atmosphere the frequency of entries is qualitatively consistent with the data of frequency of bolide phenomena recorded using satellites (according to NASA).