  We solved the Poisson equations, obtaining their exact solution in elementary
functions for the rotation matrix of a free asymmetrical body with angular
velocity vector lying on separatrices. This allows us to discuss the temporal
evolution of Dzhanibekov's nut directly in the Laboratory system, where it is
observed. The rotation matrix depends on two parameters with clear physical
interpretation as a frequency and a damping factor of the solution. Qualitative
analysis of the solution shows that it properly describes a single-jump
Dzhanibekov effect.
