on highly similar heliocentric orbits. At some point in the past, the pair of asteroids became gravitationally unbound due to rotational fission induced by the YORP-effect or from a collisional breakup of the parent body. After the discovery of Balams two satellites by Bill Merline (inner moon) and Franck Marchis (outer moon) in 2002 and 2008, respectively, Czech physicist David Vokrouhlický identified the unbound secondary in 2009. Based on backward orbit integrations, it is thought that Balam and form a secured asteroid pair that became separated approximately 400,000 years ago. Notes References External links IAUC 7827 Franck Marchis entry for 3749 Balam Orbits of Binary Asteroids with Adaptive Optics (VLT images) Lightcurve Database Query (LCDB), at www.minorplanet.info Asteroids and comets rotation curves, CdR – Geneva Observatory, Raoul Behrend 003749 Discoveries by Edward L. G. Bowell Named minor planets 003749 19820124