  In this short paper, we formally derive the thin spray equation for a steady
Stokes gas, i.e. the equation consists in a coupling between a kinetic (Vlasov
type) equation for the dispersed phase and a (steady) Stokes equation for the
gas. Our starting point is a system of Boltzmann equations for a binary gas
mixture. The derivation follows the procedure already outlined in
[Bernard-Desvillettes-Golse-Ricci, arXiv:1608.00422 [math.AP]] where the
evolution of the gas is governed by the Navier-Stokes equation.
