In the near future, to study the surface layer of various cosmic bodies (planets, asteroids, comets), the use of high-velocity penetrators capable of penetrating it due to their available kinetic energy reserve is considered. The penetration depth of penetrators when choosing their design parameters can be predicted on the basis of empirical dependencies, which are the results of processing experimental data on the penetration of non-deformable impactors into various geomaterials. A comparative analysis of such dependencies obtained for impactors with an ogival and conical head shape and used by both Russian and foreign researchers is carried out. For the research module-penetrator with a diameter of 150 mm and a mass of 50 kg, the depth of its penetration into geomaterials with contrasting strength properties at initial interaction velocities in the range from 100 to 1000 m/s was estimated. It is found that with the selected parameters of the penetrator and its velocity of 1000 m/s, the penetration depth can range from several meters in the case of medium-hard rock to several tens of meters in the case of loose soil. In accordance with some of the analyzed empirical dependencies, the manifestation of a scale effect during penetration is recorded, which consists in the fact that the ratio of penetration depths of geometrically similar impactors with a constant ratio of their mass to the cube of diameter exceeds the coefficient of geometric similarity.