Spectroscopy of the Veritas Family: Toward a Compositional Understanding

We have started a near-infrared spectroscopic study of the Veritas asteroid family. This family is of particular interest for several reasons: 1) This 8.2 million-year-old family contains fresh fragments of a primitive parent body (Nesvorney et al., 2005). 2) Interplanetary dust from the Veritas collision makes up over 25% of interplanetary dust particles (IDPs) in our collections and is thought to contribute over 7,000 tons of dust accreted by Earth each year (Nesvorny et al., 2006). 3) The Veritas parent body formed in the same region as the Themis family (3.13 and 3.17 AU respectively) and likely out of similar nebular condensates. 4) The Veritas parent body seems to have formed beyond the frost line and some fragments may not have been entirely aqueously processed, thereby retaining water-ice reservoirs for the age of the Solar System (analogous to what has been proposed for the Themis family; Hsieh and Jewitt, 2006). Although the visible spectra of Veritas members hint at aqueous processing (DiMartino et al., 1997), none of Veritas family asteroids have been studied in the near-infrared - the most diagnostic region of the presence and type of hydrated silicates (e.g., Rivkin et al., 2002). Our main goals include: 1) spectroscopic comparisons of Themis and Veritas families to further constrain asteroid formation and space weathering processes in the outer-belt; 2) test proposed models for the thermophysical evolution of primitive asteroid parent bodies and their fragments (e.g.,Vilas and Sykes, 1996). This study will observe 15 Veritas members over the next 2 years. Observations start in November 2007.