The space flinched slightly and froze again, as if nothing had happened. And nothing happened. Only a stone ten kilometers in diameter, which was listed in the astronomical catalogs of local inhabitants as 1983 UH, changed its orbit by a couple of thousandths of an arc second. Although, it is here and now - a couple of thousandths. But approaching the star, a giant rotating block with a changed orbit will fly into just one of the oceans of the blue planet. At speed - as the natives are still alive - twenty-five kilometers per second. Well, and then...