(66652) Borasisi and Pabu

compiled by Wm. Robert Johnston
last updated 3 November 2012

Orbital elements and other data (Assumed or derived values in parenthesis, my estimates in italics and parenthesis. Source identifications in brackets, see this link for sources):

orbital data, primary (osculating elements) [JPL]:
semimajor axis a: 43.6151002599504 AU
orbital period P: 288.0471 y (=105211 d)
eccentricity e: 0.0870336266829969
perihelion distance q: 39.8191199061844 AU
aphelion distance Q: 47.41108061 AU
inclination i: 0.562670278778104°
argument of perihelion omega: 195.120505653145°
ascending node OMEGA: 84.6116071941318°
mean anomaly M: 46.1445770568453°
perihelion passage TP: 1968-02-28.3492371
Epoch: 30 JAN 2005
data arc: 1999-2004 (31 obs.)

orbital data, secondary:
semimajor axis a: 4,528 ± 12 km [G11b]
semimajor axis/primary radius a/Rp: (55)
orbital period P: 46.2888 ± 0.0018 d [G11b]
eccentricity e: 0.4700 ± 0.0018 [G11b]
inclination to ecliptic i: 54.31° ± 0.30° [G11b]
ascending node OMEGA: 70.44° ± 0.47° [G11b]
longitude of periapsis: 238.85° 0.66± ° [G11b]
mean longitude at epoch: 214.40° ± 0.50° [G11b]
Epoch: 21.5 DEC 2000 [G11b]

other data, primary:
diameter: 166 km? [N04a]
absolute magnitude H: 5.82 [JPL]
rotation period: ?
amplitude delta M: <0.05 [L06a]
color index B-V: 0.820 ± 0.170 [H02a]
color index V-R: 0.646 ± 0.058 [H02a]
color index R-I: ?
slope parameter G: (0.15) assumed
geometric albedo: 0.12 (477 nm) [N04a]
0.17 (R-band) [N04a]
mass: (3.433 ± 0.027) x 1018 kg [G11b]
density: (1 g/cm3) assumed
type: ?

other data, secondary:
diameter: 137 km? [N04a]
diameter ratio Ds/Dp: 0.83 [N04a]
component magnitude difference: (0.4)
mass: (1.34 ± 0.27) x 1018 kg [N04a]
rotation period: ?

--(66652) Borasisi--discovery and notes:

Primary discovered 8 September 1999 by C. Trujillo, J. K. Luu, and D. C. Jewitt from Mauna Kea, Hawaii, USA. Alternate designation 1999 RZ253, name assigned 26 September 2007.

Companion detected 23 April 2003 by K. S. Noll, D. C. Stephens, D. Cruikshank, W. Grundy, W. Romanishin, and S. Tegler using the Hubble Space Telescope. Earlier HST observations on 9 November 2001 suggested a companion. Name (66652) I Pabu assigned 26 September 2007.

See more information and links at Asteroid/Comet Connection Catchall Catalog page

--Links, more technical:

--Links, less technical:

--Links to ADS abstracts:


© 2003-2011, 2012 by Wm. Robert Johnston.
Last modified 3 November 2012.
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