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The distribution of rotation rates of small (D = 3–15 km) main-belt asteroids is analyzed in the context of the probable influence of solar radiation on the rotation of asteroids (YORP effect). It is demonstrated that the evolution of this distribution with heliocentric distance (i.e., the presence of well-marked slow and fast rotation excesses in the inner part of the belt, which become less noticeable in the middle part and are almost indistinguishable in the outer part) is well accounted for by the YORP effect. The influence of this effect on the studied asteroid population is rather weak compared to its influence on near-Earth asteroids, which are 3–4 times smaller on average and with ~3 times more intense solar irradiation; however, it is still sufficiently significant to be identified reliably in the available observational data. [ABSTRACT FROM AUTHOR]

Lightcurve observations of 16 near-Earth objects (NEOs) and 2 Mars-crossers in 1996–1999 from three observational sites are presented. Eight objects were observed shortly after their discovery within the follow-up program of NEO observations. We were able to determine rotation periods for 14 asteroids. For 8 objects (5626, 5732, 1998 FM5, 1998 FX2, 1998 UT18, 1998 VO33, 1999 RQ36, 1999 US3) our determinations constitute new results while in the remaining 6 cases (3200, 4341, 7025, 7822, 11066, 1992 QN) we could improve or confirm previously published periods. We also put constraints on the spin vector of 3200 Phaethon. [Copyright &y& Elsevier]