Asteroids with Satellites Database--Johnston's Archive

2005 SF278

compiled by Wm. Robert Johnston
last updated 23 September 2018

--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, 4:7 resonance


orbital data, primary (osculating elements) [JPL] :
semimajor axis a: 43.4787 AU
orbital period P: 286.7 yr
(= 104716 d)
eccentricity e: 0.18299
perihelion distance q: 35.52253 AU
aphelion distance Q: 51.4348 AU
inclination i: 13.353138°
argument of perihelion ω: 321.312°
ascending node Ω: 101.55275°
mean anomaly M: 353.2239°
perihelion passage TP: 2023 Aug 15
Epoch: 2018 Mar 23
data arc: 2004-2015 (174 obs.)
Earth MOID: 34.5453 AU
Jupiter Tisserand invariant TJ: 5.65
Neptune Tisserand invariant TN:2.992 [*D]


orbital data, secondary:
semimajor axis as: 10275 ± 25 km (separation) [B18d]
orbital period Ps: 150 d [*E]
eccentricity es: ?
normalized ang. mom. αL: ?

other data, system (combined):
absolute mag. H: 6.5 [MPC]
slope parameter G: (0.15) [*A]
effective diameter dE: 220 km [*E]
geometric albedo: (0.09 ) [*A]
color index U-B: ?
color index B-V: ?
taxonomic type: RR (G-mode) []
mass m: ?
density ρ: (1 g/cm3) [*A]
Hill radius rH: 570000 km [*E]

other data, primary:
diameter dp: 165 km [*E]
rotation period RPp: ?
amplitude in mag., rotational ΔM: ?
pole direction Β, λ: ? , ?


other data, secondary:
diameter ds: 145 km [*E]
diameter ratio ds/dp: 0.879 ± 0.012 [*D]
component mag. difference ΔM: 0.28 ± 0.03 [B18d]
rotation period RPs: ?

-- 2005 SF278 --discovery and notes:

Primary discovered 2005 Sep 26 from Apache Point Observatory, New Mexico, USA by A. C. Becker, A. W. Puckett, J. Kubica. Linked to prediscovery observations from 2004 Sep 22.

Companion discovered 2014 Dec 08 by S. D. Benecchi, S. S. Sheppard, K. S. Noll, and C. A.Trujillo using Hubble Space Telescope observations from Hubble Space Telescope. Announced 2018 Feb 07 [B18d].

--Links, more technical:

--Links, less technical:

--Links to ADS abstracts:


© 2018 by Wm. Robert Johnston.
Last modified 23 September 2018.
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