Аңдатпа
We consider the radiation pressure effects in the most luminous astrophysical objects, stellar winds of the O-B stars and the broad-absorption-line (BAL) quasistellar object (quasar) (QSO) matter outflows. Although the objects have different physical natures, there are many similarities in the behaviours of their gas envelopes in the strong radiation fields. We discuss both smooth and structured stellar wind models, and the dynamic and kinetic instability of the winds. We consider also the dynamics of the absorbing gas in the BAL QSO, the nature of the line-locking effects and the sources of the outflowing gas.