CDROM/AJ/V112/P2319 Asteroid Masses (Hilton, Seidelmann & Middour 1996) ================================================================================ Prospects for Determining Asteroid Masses James L. Hilton, P. Kenneth Seidelmann and Jay Middour <1996, AJ, 112, 2319> =1996AJ....112.2319H ================================================================================ Abstract: The orbits of 4583 main belt asteroids are integrated orbits for 57 years and searched for asteroid-asteroid encounters from which it may be possible to determine the masses of 23 of the largest asteroids (diameter >= 200 km) and 11 smaller asteroids. The search is conducted using a scattering formula which serves as a useful filter for identifying encounters that can lead to a mass determination. A total of 460 such encounters were found. The ten most useful of these encounters are examined in detail. The results show that, to make a reliable mass determination, the mean distance of the perturbed asteroid must be known to within a few times 10^-8 AU. An observing program targeting the asteroids listed here would have a substantial impact on our knowledge of asteroid masses and densities. File Summary: -------------------------------------------------------------------------------- File Name Lrecl Records Explanations -------------------------------------------------------------------------------- table2.dat 70 450 Significant encounters involving large asteroids table2.tex 96 491 AASTeX version of table2.dat -------------------------------------------------------------------------------- Byte-by-byte Description of file: table2.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1-11 A11 --- Date Date of least separation 12-13 2X --- --- Blank 14-27 A14 --- Larger Name of larger asteroid 28-29 2X --- --- Blank 30 A1 --- LType *Tholen et al. 1989 type of Larger 31-32 2X --- --- Blank 33-52 A20 --- Smaller Name of smaller asteroid 53 1X --- --- Blank 54 A1 --- SType *Tholen et al. 1989 type of Smaller 55-62 F8.4 AU Dist Distance between on Date at 0 hr. UT 63-67 I5 d Time Number of days distance less than 0.05 AU 68-70 I3 --- Qual *Quality factor, from 1 to 5 -------------------------------------------------------------------------------- Notes for file: table2.dat -------------------------------------------------------------------------------- LType, SType: First letter of the classification from Tholen, D. J. 1989, in Asteroids II, edited by R. P. Binzel, T. Gehrels, & M. S. Matthews, (University of Arizona Press, Tucson) p. 1139. Qual: The quality factor is an estimate of the likelihood of producing a useful mass from the encounter. The quality factor runs from 1 (low probability of significant deflection) to 5 (high probability) and is computed as the logarithm of the computed deflection angle in arc seconds, rounded to the nearest integer. -------------------------------------------------------------------------------- ================================================================================ (End) Lee Brotzman [ADS] 05-Nov-1996