  Clumps of material orbiting a black hole may be disturbed, somewhat like
comets in the Kuiper belt, to relatively small periastron orbits. Each
periastron passage changes the orbital parameters in such a way that the orbit
becomes more and more eccentric and the angular momentum approaches the
critical value for tidal capture. When this value is reached, the body is
suddenly caught by the relativistic potential to the last periastron (occurring
at two Schwarzschild radii for a non rotating black hole). In this process the
transfer of orbital into internal energy heats the body before it makes a few
more turns toward the horizon of the black hole. Because of strong relativistic
effects this last bright message from the object is seen as a quasi-periodic
flare. Assuming that a black hole may be fed by a large number of such small
debris we calculate light curves expected from such events. We investigate the
resemblance of the Fourier spectra of such light curves with those of observed
QPOs.
