In the exploration of the solar system, it will soon be of interest to recover instrumented probes, which, if they are not decelerated in some fashion in space, will approach Earth at velocities as high as 140,000 fps. The possibility of decelerating such a recovery vehicle by atmospheric braking is examined. Since this velocity is well into the meteor range, data on meteorites are used to orient the analysis. Meteorites are known to cover a wide range of sizes from a few microns to hundreds of feet in diameter. There is evidence, furthermore, that , in the intermediatesize range from a few inches to a foot or two in diameter, only objects in the lower meteor velocity range survive. Rational designs of recoverable deep-space probes are of this intermediate size. Analysis is performed which shows that , whereas very small and very large objects may survive throughout the meteor velocity range, there may well be an upper limit to re-entry velocity of about 50,000 to 60,000 fps for objects of intermediate size. The reason for this upper limit appears to be that , at meteor velocities, the dominant mechanism of heat transmission is radiation. This provides a much more effective route for the transfer of energy than the convective heat transfer processes associated with lower entry velocities.
