Preliminary discussion on the origin of Lei-gong-mo (tektites)

The specimens of lei-gong-mo (tektites) were collected from Hainan Island and Leizhow Peninsula during the period from 1963 to 1975. The distribution, forms, sculpture, abration surface (bald spot), internal structure and chemical composition of lei-gong-mo are discussed. Studies of these materials lead to the following conclusions: (1) the specimens of lei-gong-mo can be morphologically divided into eight types; (2) the sculptures on the surface of lei-gong-mo are probably due to the corrosion effect of volcanic gas, and the abration surface due to the aerodynamic corrosion; (3) the folded structures in the layered lei-gong-mo (Muong Nong-type tektite) seem hardly to be formed by an impact of meteorites, but they might be produced in the magma flow process when the lei-gong-mo was melting within the crater vent; and (4) the comparison of its chemical composition with that of basalt from Hainan Island does not show that lei-gong-mo came from the local volcano. The hypothesis of the lunar volcanic origin of tektites is examined

Analysis of potential locations of asteroidal moonlets

In this study, the potential locations of asteroidal small satellites (also called moonlets) with quasi-circular mutual orbit are analyzed. For the motion of the moonlets, only the solar gravity perturbation and the primary's 2nd degree-and-order gravity field are considered. By eliminating of short periodic terms, the dynamical behavior of the Hamiltonian for the moonlets is investigated. The observational data of some high size ratio binary asteroids show that the orbits of the moonlets lie close to the classical Laplace equilibria, which reach global minimum values of the Hamiltonian. It is found that tides or Yarkovsky effects alone cannot account for the reason why the orbits of asteroidal moonlets are not exactly at the classical Laplace equilibria. The analysis in this study is expected to provide useful information for the potential locations of asteroidal moonlets, and contribute to principles to relate predictions to observations