Asteroids with Satellites Database--Johnston's Archive

(79360) Sila-Nunam

compiled by Wm. Robert Johnston
last updated 11 May 2014
under construction--testing upgrades!

--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: 44.1329 AU
orbital period P: 293.192 yr (= 107088.4 d)
eccentricity e: 0.015946
perihelion distance q: 43.4292 AU
aphelion distance Q: 44.8367 AU
inclination i: 2.23732°
argument of perihelion ω: 214.91°
ascending node Ω: 304.32087°
mean anomaly M: 337.33°
perihelion passage TP: 2032 Nov 08
Epoch: 2014 May 23
data arc: 1997-2014 (244 obs.)
Earth MOID: 42.4388 AU
Jupiter Tisserand invariant TJ: 5.937
Neptune Tisserand invariant TN:3.10 [*D]


orbital data, secondary:
semimajor axis as: 2777 ± 19 km [G12a]
separation/primary radius as/rp:22 [*D]
separation/Hill radius as/rH:0.0035 [*D]
orbital period Ps: 12.51 ± 0.0000217 d [B14a]
eccentricity es: 0.018 ± 0.006 [B14a]
inclination is:103.51°± 0.39 [G12a]
ascending node Ωs:140.76°± 0.66 [G12a]
argument of pericenter ωs:326°± 59 [G12a]
mean anomaly M:16.3°± 1 [G12a]
normalized ang. mom. αL: ?

other data, system (combined):
absolute mag. H: 5.2 [MPC]
5.56 ± 0.04 [V14a]
slope parameter G: 0.15 [*A]
effective diameter dE: 343 ± 42 km [V12a]
geometric albedo: 0.086 ± 0.026/0.017 [G12a]
color index U-B: 0.73 [J07a]
color index B-V: 1.08 [B05b]
color index V-R:0.66± 0.04 [B05b]
color index B-R:1.74 [B05b]
color index V-I:1.25± 0.03 [B05b]
color index R-J:1.4 [*D]
color index V-J:2.06± 0.03 [B05b]
color index J-H:0.38± 0.08 [D06a]
color index V-H:2.45± 0.08 [B05b]
taxonomic type: ? RR (BBRB) [*B05c]
mass m: 1.08x1019 ± 2.2x1017 kg [G12a]
density ρ: 0.72 ± 0.37/0.22 g/cm3 [G12a]
Hill radius rH: 790000 km [*D]

other data, primary:
diameter dp: 249 ± 30/31 km [V14a]
color index V-I:1.26± 0.04 [B08d]
rotation period RPp: ?
amplitude in mag., rotational ΔM: ?
pole direction : ? ; ?


other data, secondary:
diameter ds: 236 ± 28/29 km [V14a]
diameter ratio ds/dp: 0.944 [G12a]
component mag. difference ΔM: 0.12 [*G11a]
color index V-I:1.33± 0.05 [B08d]
rotation period RPs: ?

-- (79360) Sila-Nunam --discovery and notes:

Primary discovered 1997 Feb 03 from Mauna Kea Observatory, Hawaii, USA by J. X. Luu, D. C. Jewitt, C. A. Trujillo, and J. Chen. Alternate designation(s): 1997 CS29 . Permanent number assigned 2004 May 04.

Named 2012 Jan 09 for the mythological Inuit god of the sky [MPC77871].

Companion discovered 2002 Oct 22 using HST observations from Hubble Space Telescope. Announced 2005 Oct 06. Permanent designation Nunam, assigned 2012 Jan 09; named for the mythological Inuit goddess of the earth [MPC77871].

--Links, more technical:

--Links, less technical:

--Links to ADS abstracts:


© 2005-2012, 2014 by Wm. Robert Johnston.
Last modified 11 May 2014.
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