Carl Melis
University of California, Los Angeles (UCLA)
 

"Catastrophic Collisions in the Terrestrial Planet Zone and the Epoch of Terrestrial Planet Formation around Intermediate Mass Stars"
 

We have completed an extensive search for stars hosting terrestrial planet zone dust by cross-correlating the Tycho-2 and IRAS catalogs. Near-infrared to far-infrared excess emission has been discovered towards a ~12 Myr old, A-type member of the Upper-Centaurus-Lupus association. The hot dust temperature (~750 K) in combination with the high fractional infrared luminosity (0.4%) suggest a recent catastrophic collision between rocky bodies in this intermediate mass star’s inner planetary system. Synthesis of all published incidences of intermediate mass stars with evidence for terrestrial planet zone dust suggests that Moon-forming events around intermediate mass stars occur when the star is ~10-30 Myr old.