ABSTRACT

Table 8.1 shows the characteristics of a number of asteroids, chosen because they span the period from the first discovery to comparatively recent times and also because they illustrate a wide range of characteristics. The orbits of most of them are shown in projection in Figure 8.1 without regard to the relative directions of their perihelia. Gravitational forces in large bodies tend to force them into a shape of minimum energy, which is a sphere, but the mechanical strength of the material of small bodies can enable them to retain a nonspherical form. It can be shown that the largest asteroids, those with diameters more than about 300 km, are spherical or nearly so because the strength of their material is insufficient to support much departure from spherical symmetry (Section Q.7.1).