Asteroids with Satellites Database--Johnston's Archive

(303712) 2005 PR21

compiled by Wm. Robert Johnston
last updated 20 September 2014

--Orbital and physical data--

(See this page for definitions of quantities; source codes in brackets, see this link for full references; *A, *D, and *E indicate assumed, derived, and estimated values, respectively.)

dynamical type, primary: TNO, Cubewano

orbital data, primary (osculating elements) [JPL] :
semimajor axis a: 44.045 AU
orbital period P: 292.318 yr
(= 106769.2 d)
eccentricity e: 0.10138
perihelion distance q: 39.5799 AU
aphelion distance Q: 48.510 AU
inclination i: 1.34656°
argument of perihelion ω: 310.05°
ascending node Ω: 339.1618°
mean anomaly M: 49.18°
perihelion passage TP: 1974 Jun 17
Epoch: 2014 May 23
data arc: 2005-2012 (46 obs.)
Earth MOID: 38.5631 AU
Jupiter Tisserand invariant TJ: 5.905
Neptune Tisserand invariant TN:3.09 [*D]

orbital data, secondary:
semimajor axis as: 3600 ± 300 km (separation) [G12b]
separation/primary radius as/rp:32 [*E]
separation/Hill radius as/rH:0.0056 [*E]
orbital period Ps: 22 d [*E]
eccentricity es: ?
normalized ang. mom. αL: ?

other data, system (combined):
absolute mag. H: 6.1 [MPC]
slope parameter G: (0.15) [*A]
effective diameter dE: 265 km [*E]
geometric albedo: (0.09 ) [*A]
color index U-B: ?
color index B-V: ?
taxonomic type: ?
mass m: ?
density ρ: (1 g/cm3) [*A]
Hill radius rH: 640000 km [*E]

other data, primary:
diameter dp: 227 km [*E]
rotation period RPp: ?
amplitude in mag., rotational ΔM: <0.28 [B13a]
pole direction Β, λ: ? , ?

other data, secondary:
diameter ds: 137 km [*E]
diameter ratio ds/dp: 0.603 [N08d]
component mag. difference ΔM: 1.1 [I8925]
rotation period RPs: ?

-- (303712) 2005 PR21 --discovery and notes:

Primary discovered 2005 Aug 09 from Cerro Tololo Observatory, La Serena, Chile by ?. Permanent number assigned 2011 Nov 10.

Companion discovered 2007 May 20 by K. S. Noll, W. M. Grundy, S. D. Kern, H. F. Levison, and D. C. Stephens using Hubble Space Telescope observations from Hubble Space Telescope. Announced 2008 Mar 04 [N08d].

--Links, more technical:

--Links, less technical:

--Links to ADS abstracts:

© 2008-2011, 2014 by Wm. Robert Johnston.
Last modified 20 September 2014.
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