PSJC #104 January 20, 2012

Humberto Campins

Origin of Spacecraft-Accessible Near-Earth Asteroids

The near-Earth asteroids (NEAs) currently targeted by sample return spacecraft are: 1999 RQ36 (NASA's OSIRIS-REx), 1999 JU3 (JAXA's Hayabusa 2) and 1999 FG3 (ESA's Marco Polo-R). Dynamical models point to an inner-belt (2.15 < a < 2.5 AU), low-inclination (i < 12 degrees) origin for all three objects. In addition, these three NEAs have geometric albedos lower than 7%. The inner-belt contains three low-albedo families, Erigone (a ~ 2.37 AU) and Polana ( a ~ 2.42 AU) and Sulamitis (a ~ 2.45 AU), plus a population of low-albedo and low-inclination asteroids, as possible sources. Dynamical, spectral and albedo considerations can be used to further constrain the origin of all three NEAs.