  By obtaining the assumption that planetary dust particles can escape from the
gravitational attraction of a planet, we consider the possibility for the dust
grains to leave the star's system by means of the radiation pressure. By taking
the typical dust parameters into account, we consider their dynamics and show
that they can reach the deep cosmos, taking part in panspermia. It has been
shown that, during $5$ billion years, the dust grains will reach $10^5$ stellar
systems, and by taking the Drake equation into account, it has been shown that
the whole galaxy will be full of planetary dust particles.
