Thermophysical Characteristics of OSIRIS-REx Target Asteroid (101955) Bennu
Abstract
In this work, we investigate the thermophysical properties, including thermal inertia, roughness fraction and surface grain size of OSIRIS-REx target asteroid (101955) Bennu by using a thermophysical model with the recently updated 3D radar-derived shape model (Nolan et al., 2013) and mid-infrared observations (Müller et al. 2012, Emery et al., 2014). We find that the asteroid bears an effective diameter of 510+6 -40 m, a geometric albedo of 0.047+0.0083 -0.0011, a roughness fraction of 0.04+0.26 -0.04, and thermal inertia of 240+440 -60 Jm-2s-0.5K-1 for our best-fit solution. The best-estimate thermal inertia suggests that fine-grained regolith may cover a large portion of Bennu's surface, where a grain size may vary from 1.3 to 31 mm. Our outcome suggests that Bennu is suitable for the OSIRIS-REx mission to return samples to Earth.
- Publication:
-
Asteroids: New Observations, New Models
- Pub Date:
- January 2016
- DOI:
- 10.1017/S1743921315006985
- arXiv:
- arXiv:1511.02713
- Bibcode:
- 2016IAUS..318..218Y
- Keywords:
-
- radiation mechanisms: thermal;
- minor planets;
- asteroids: individual: (101955) Bennu;
- infrared: general;
- Astrophysics - Earth and Planetary Astrophysics
- E-Print:
- 3 pages, 1 figures, accepted to IAU Symposium 318: Asteroids: New Observations, New Models