ON THE RELATIVISTIC MOTION OF (1566) ICARUS

We collected 727 astrometric observations of Icarus from the interval 1949-1987 to use them for the orbit improvement when studying the motion of the asteroid. To verify the predictions of the general relativity, we determined the relativity factor-lambda included to the equations of motion; we used the simple form of relativistic equations of motion written in the Painleve's coordinates, and based on the solution of one-body Schwarzschild problem. We also made an attempt to determine nongravitational effects which appeared to be insignificant in the Icarus' motion. We may conclude that our analysis of the motion of Icarus fully confirmed the predictions of general relativity; we found a value of the relativity factor-lambda as being close to the theoretical value lambda = 1 with the probability of 99.8%, namely: 0.985 +/- 0.033 less-than-or-equal-to lambda less-than-or-equal-to 1.013 +/- 0.018.