Mathematical Modeling of Asteroid Falling into the Ocean

Today, experimental information about large-scale collision tsunami is not available. That is why one of the main tools of studies is mathematical modeling. This paper considers falling of stone asteroid with diameter 1 km into the ocean 4 km deep. This asteroid collides with the Earth at a speed of 22 km/s at angles 30, 60 and 90 degrees. Calculation of space body collision with a barrier is split into two stages. At the first stage, using finite-element code LS- DYNA® [1] and super computer SKIF-URAL of South-Ural State University under the support of OCC “STRELA”, the process of interaction of body with the barrier was calculated. Analysis of calculation data shows that for the angle of incidence 60 and 90 degrees, the results differ slightly. Even for the angle of incidence 30 degrees, we do not have big difference. That is why, one is to expect that the impact of tsunami on the sea shore for these angles of collision will be practically the same. Due to this reason, at the second stage of calculations, we considered the case of axisymmetric penetration of asteroid into the ocean. For describing cylindrically diverging surface wave and its impact on the shore with regard for the shelf profile, a special code was developed, in which approximation of shallow water was realized [3, 4]. It was given empirical formulae for calculation of the height of remote wave that is formed with underwater nuclear explosions [5]. Compared values are in good agreement. This means that using the approach to assessing the parameters of tsunami, which is proposed in this paper, is acceptable both for qualitative and quantitative description of this physical phenomenon. As tentative assessments showed, the aftereffects of the falling of a stone asteroid with diameter ~1 km may be destructive for the ocean shore. Calculations showed that the wave height on the shelf increases from 60 to 100 m. Then the wave height on the shallow water decreases.