Thermophysical Modeling of NEOWISE Observations of DESTINY⁺ Targets Phaethon and 2005 UD

September 2019 • 2019AJ....158...97M

Authors • Masiero, Joseph R. • Wright, E. L. • Mainzer, A. K.

Abstract • Thermophysical models allow for improved constraints on the physical and thermal surface properties of asteroids beyond what can be inferred from more simple thermal modeling, provided that a sufficient number of observations is available. We present thermophysical modeling results of observations from the Near-Earth Object WISE (NEOWISE) mission for two near-Earth asteroids which are the targets of the DESTINY⁺ flyby mission: (3200) Phaethon and (155140) 2005 UD. Our model assumes a rotating, cratered, spherical surface, and employs a Monte Carlo Markov Chain to explore the multidimensional parameter space of the fit. We find an effective spherical diameter for Phaethon of {4.6}_-0.3^+0.2 km, a geometric albedo of p _V = 0.16 ± 0.02, and a thermal inertia Γ = 880 {}_-330⁺⁵⁸⁰, using five epochs of NEOWISE observations. The best model fit for (155140) 2005 UD was less well constrained due to only having two NEOWISE observation epochs, giving a diameter of 1.2 ± 0.4 km and a geometric albedo of p _V = 0.14 ± 0.09.

Links

• PDF https://iopscience.iop.org/article/10.3847/1538-3881/ab31a6/pdf
• PDF https://stacks.iop.org/1538-3881/158/97/pdf
• PREPRINT http://arxiv.org/abs/1907.04518
• DATA https://irsa.ipac.caltech.edu/bibdata/2019/M/2019AJ....158...97M.html
• ELECTR https://doi.org/10.3847%2F1538-3881%2Fab31a6