A Shape Model of the Taxonomic A-Class Asteroids 446 Aeternitas

We acquired dense rotational lightcurves for the taxonomic A-class asteroid 446 Aeternitas during three apparitions in 2006, 2007-2008, and 2009. Our results show that 446 Aeternitas is a prograde rotator, has a distinct angular shape, and is moderately elongated. Several planar areas in the convex shape model suggest concavities, possibly large craters or saddles. These features suggest that 446 Aeternitas is likely to be a collisional fragment. We found a pole solution of ? = +52o, ? = 356o with no mirror solution apparent. However, low chi-square pole solutions centered on ecliptic longitude ? = 210o cannot be ruled out, leaving the ecliptic longitude of 446 Aeternitas unconstrained. Lightcurves measured over three asteroid apparitions were used during the inversion process to determine a refined rotational period of 15.73743 ± 0.00005 h. Typical errors for ecliptic latitude and longitude values are ± 10 degrees.