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The lightcurves of 47 Hilda asteroids presented in Dahlgren et al. (1998, Icarus 133, 247-285) have been analyzed. The Hilda population has mean lightcurve amplitudes significantly larger than those of main-belt asteroids of similar sizes. This is due to the very large mean amplitudes (0.31 mag) of the small (D < 60 km) D-type Hilda asteroids. The spin rate distribution of the Hilda asteroids is markedly non-Maxwellian, mainly due to a large fraction of slowly rotating objects. More than half of the observed population have rotation periods longer than 12 h. The spin rate versus size diagram has a U-shape with slow spin rates at intermediate sizes. At smaller sizes (D < 60 km) where the Hilda population is totally dominated by D-type objects (Dahlgren and Lagerkvist 1995, Astron. Astrophys. 302, 907-914; Dahlgren et al. 1997, Astron. Astrophys. 323, 606-619) there is a large increase in the scatter of the spin rates, and an increase of the mean amplitudes of these (D-type) Hilda asteroids. This strongly suggests a connection between taxonomic type and collisional evolution among objects in the Hilda population. Possible interpretations of these results are discussed in terms of an early heating event in the Solar System and subsequent collisional evolution of the Hilda population. Key Words: asteroids; asteroids photometry; asteroids rotation; asteroids composition; surfaces asteroids.

The results of a photometric survey of Hilda asteroids are presented. We have obtained 224 lightcurves of 47 Hilda asteroids. A wide span of rotation periods have been found, ranging from 2.851 to 31 h. However, indications of rotation periods longer than 100 h were found for two objects. The largest lightcurve amplitude found is 1.38 mag, and 13 additional objects have observed amplitudes [greater than or equal to]0.30 mag. Improved absolute magnitudes have been obtained for 20 objects as well as new V-R color indices for 17 of these. Improved albedos, derived from the new absolute magnitudes, have been obtained for 10 Hilda asteroids. The V-R color indices range between 0.38 and 0.49 mag, indicating that only P- and D-type asteroids are present among these asteroids. A probable taxonomy was assigned to four Hilda asteroids (one P-type and three D-types) which previously were unclassified. The Hilda Asteroid 3694 Sharon was observed at low solar phase angles, and the obtained lightcurves indicate a reduced to nonexisting opposition effect for this asteroid. One Hilda asteroid, 2067 Aksnes, may be in a state of precession as no satisfactory two-maxima and two-minima lightcurve could be fitted to the data. However, the short damping time scale makes this very unlikely. This favours a four-maxima and four-minima lightcurve of 2067 Aksnes, which is a better fit to the data than a two-maxima and two-minimal lightcurve. The Hilda Asteroid 3415 Danby has a very short rotation period (P = 2.851 [+ or -] 0.003 h), making Danby the fastest spinning asteroid known within its size range (D [approximately] 50 km). Due to its fast spin some constraints can be set on 3415 danby's internal structure and mean density. The assumption that 3415 Danby is a rubble-pile, with its shape governed by hydrostatic equilibrium, leads to an unrealistically high mean density. On the other hand, assuming that 3415 Danby has internal strength results in a mean density larger than 1.4 g [cm.sup.-3] Key Words: asteroids photometry; asteroids rotation.

The first results of speckle interferometry carried out with the 3.5-m telescope of the C.A.H.A. (Almería, Spain) during a run in July, 2005 are presented. Forty nine stars with separations between 0″058 and 2″1 were observed under good seeing conditions. On the basis of these observations three improved orbits are presented. The Time Allocation Committee's report with a high scientific qualification to our proposal is included. It confirms the relevance of binary and multiple star research in modern astronomy and the great significance of large telescopes in this kind of studies as well. [ABSTRACT FROM PUBLISHER]