X-ray emission from planet Venus. Comparison with Chandra observations.

It is a goal of the presentation to show that recently observed X-ray emission from non-magnetic planets Venus and Mars (Ref. 1) can be explained by the same mechanism that was originally proposed for explanation of X-ray emission from comets (Ref. 2), namely as combination of Bremmstrahlung and line K shell radiation produced in interaction of energetic electrons with neutral atmosphere. It is argued that fluorescence of solar X-rays in no way cannot be the source of the observed emission. Numerical simulation are presented that show how energetic electrons can be produced by modified two stream instability developing in planetary mantle as the result of interaction of counterstreaming plasma populations - solar wind and ionospheric cold plasma. Comparison with experimental data is also carried out. 1) Dennerel et al Astronomy and Astrophysics, 386, 319, 2002 2) Bingham et al Science, 275, 49, 1997 Shapiro et al J Geophys, Res, 104, 2587, 1999