Fig. 5
From: Asteroid spin-rate studies using large sky-field surveys
This figure is reproduced from Chang et al. (2015, 2016)
Light-curve amplitude vs. spin rate (left) and spin-rate distribution (right) for the C- (upper) and the S-type (lower) asteroids. The gray and red filled circles are objects of the LCDB and the PTF-U2s, respectively. The number of asteroids used in the statistics is given in each plot. The spin-rate limits, \(P \sim 3.3 \sqrt{(1 + \Delta m)/\rho }\) (Pravec and Harris 2000), are represented by dashed, dot-dashed, and dotted lines for rubble-pile asteroids with bulk densities of \(\rho =\) 3, 2, and \(1\,\text{g}\,\text{cm}^{-3}\), respectively. The spin-rate distributions use only asteroids of \(3< D < 20\) km.