The Relative Sizes of Transneptunian Binaries: Evidence for Different Populations from a Homogeneous Data Set
Abstract
A unique feature of Transneptunian Objects is the prevalence of binaries made up of comparably-sized components. Nearly-equal-brightness binaries are especially common in the low inclination Cold Classicals where all companions differ by Δmag < 1.5. With the assumption of equal albedos, this translates to secondaries with radii half that of the primary or greater. By contrast, members of the dynamically hot population, Hot Classical, Resonant, and Scattered Disk, have a larger range of secondary sizes. Detection of satellites with magnitude differences of Δmag > 5, corresponding to secondary radii less than 10% of the primary, are rare. This is explained, in part, by detection biases that limit the detectability of faint secondaries and secondaries that are close to their primary. However, the lack of companions with Δmag > 1.5 at separations of more than 0.1 arcsec (2900 km at 40 AU), independent of dynamical classification, is strongly constrained with the current data. This limit constrains the overall population of such secondaries.
- Publication:
-
EPSC-DPS Joint Meeting 2011
- Pub Date:
- October 2011
- Bibcode:
- 2011epsc.conf.1029N