66652 Borasisi, or as a binary (66652) BorasisiâÂÂPabu (provisional designation ), is a binary classical Kuiper belt object. It was discovered in September 1999 by Chad Trujillo, Jane X. Luu and David C. Jewitt and identified as a binary on 23 August 2003 by K. Noll and colleagues using the Hubble Space Telescope.
In 2003 it was discovered that Borasisi is a binary with the components of comparable size (about 100âÂÂ130 km) orbiting the barycentre on a moderately elliptical orbit. The total system mass is about 3.4 kg.
The companion (66652) Borasisi I, named Pabu, orbits its primary in on an orbit with a semi-major axis of and an eccentricity . The orbit is inclined with respect to the observer by about 54ð meaning that is about 35ð from the pole-on position.
The surface of both components of the BorasisiâÂÂPabu system is very red.
Borasisi is named after a fictional creation deity taken from the novel Cat's Cradle by Kurt Vonnegut. In the book, Borasisi is the Sun and Pabu is the name of the Moon:
Around 2005, Borasisi was considered as a target for the proposed New Horizons 2 after a Triton/Neptune flyby.