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We have investigated the local invariant scalar observables - energy densityand flux - which explicitly depend on the kinematics of the concerned observersin the Vaidya gravitational collapse geometry. The use of globally defined nullcoordinates allows for the definition of a unique in-vacuum for the scalarfield propagating in this background. Computing the stress-energy tensor forthis scalar field, we work out the energy density and flux for the staticobservers outside the horizon and then consider the radially in-fallingobservers who fall in from some specified initial radius all the way throughthe horizon and inside to the eventual singularity. Our results confirm thethermal Tolman-shifted energy density and fluxes for the static observers whichdiverge at the horizon. For the in-falling observer starting from far off, boththe quantities -- energy density and flux at the horizon crossing are\emph{regular and finite}. For example, the flux at the horizon for thein-falling observer from infinity is approximately 24 times the flux for theobserver at infinity. Compared with the static observers in the near-horizonregion, this is quite small. Both the quantities grow as the in-fall progressesinside the horizon and diverge at the singularity.

Black hole kinematics: the "in"-vacuum energy density and flux for different observers