SHERMAN-Based Thermophysical Model of (101955) Bennu

We apply our thermophysical model to derive regolith properties of (101955) Bennu constrained by Spitzer observations taken in 2007 (Emery et al. 2014) and 2012, before the arrival of the OSIRIS-REx spacecraft. From these observations, we will create a thermal curve and compare with photometric lightcurves, investigating physical characteristics. Our thermophysical model is described in detail by Magri et al. (2018) and treats surface roughness using a fractional coverage of hemispherical craters on each facet. In some cases we find that the thermal inertia in our models is lower than that calculated by other thermal models. This may be due to capturing inhomogeneity in our observations, or to observations at particular observing geometries (Crowell et al., 2017). (101955) Bennu, target of the OSIRIS-REx mission, will provide us with "ground-truth", allowing us to compare the results of our thermal model with the spatially resolved spacecraft measurements. This work will also allow us to interpret nonphysical parameters like crater fraction and relate them to the highly resolved measurements of the surface, soon to be available. References: Emery et al. 2014, Icarus 234, 17-35.; Magri et al. 2018, Icarus 303, 203-219; Crowell et al. 2017 ACM