66652 Borasisi

66652 Borasisi, or as a binary Borasisi–Pabu, 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.

Binary

[Image:orbit5.gif|left|thumb|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 Borasisi is a binary with the components of comparable size orbiting the barycentre on a moderately elliptical orbit. The total system mass is about 3.4 kg.
The companion 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 54° meaning that is about 35° from the pole-on position.

Physical properties

The surface of both components of the Borasisi–Pabu system is very red.

Naming

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:

Exploration

Around 2005, Borasisi was considered as a target for the proposed New Horizons 2 after a Triton/Neptune flyby.