Schematic illustration of two bodies with similar mass orbiting around a common barycenter (red cross) with elliptic orbits. Borasisi and Pabu interact similarly.
In 2003 it was discovered that 66652 Borasisi is a binary with the components of comparable size (about 120–180 km) orbiting the barycentre on a moderately elliptical orbit. The total system mass is about 3.4 × 1018 kg.
The companion (66652) Borasisi I, named Pabu/ˈpɑːbuː/ orbits its primary in 46.2888 ± 0.0018 days on an orbit with semi-major axis of 4528 ± 12 km and eccentricity0.4700 ± 0.0018. The orbit is inclined with respect to the observer by about 54° meaning that is about 35° from the pole-on position.
Borasisi, the sun, held Pabu, the moon, in his arms and hoped that Pabu would bear him a fiery child. But poor Pabu gave birth to children that were cold, that did not burn... Then poor Pabu herself was cast away, and she went to live with her favorite child, which was Earth.