Abstract
We present rotational light-curve data for Saturn's satellite Phoebe taken over the observing period prior to the Cassini mission's encounter with that moon. We find a rotation period of 9.2735 ± 0.0006 hr, a factor of 25 improvement in the rotation period's uncertainty over previously published data. This improved rotation period measurement allow s us to correlate previously observed spectral features and colors with albedo features observed by Voyager and to predict which side of Phoebe will be observed by Cassini during its 2004 June 11 encounter. The light curve, sampled at subobserver latitudes farther south than achieved by Voyager, shows evidence of surface features that cannot be explained by previously published shape models or albedo maps and that may be located in the regions in Phoebe's southern hemisphere that were unobserved by Voyager.
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