Asteroids with Satellites Database--Johnston's Archive

(136199) Eris and Dysnomia

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, scattered disk


orbital data, primary (osculating elements) [JPL] :
semimajor axis a: 67.7808 AU
orbital period P: 558.033197032487 yr
(= 203825.4 d)
eccentricity e: 0.440682
perihelion distance q: 37.911 AU
aphelion distance Q: 97.6506 AU
inclination i: 44.04451°
argument of perihelion ω: 150.9766°
ascending node Ω: 35.95312°
mean anomaly M: 204.165°
perihelion passage TP: 2256 Jul 04
Epoch: 2014 Dec 09
data arc: 1954-2014 (614 obs.)
Earth MOID: 36.9696 AU
Jupiter Tisserand invariant TJ: 4.734
Neptune Tisserand invariant TN:2.38113740956397 [*D]


orbital data, secondary:
semimajor axis as: 37460 ± 80 km [B18f]
separation/primary radius as/rp:32.2 [*D]
separation/Hill radius as/rH:0.0047 [*D]
orbital period Ps: 15.78586 ± 0.00008 d [B18f]
eccentricity es: <0.004 [B18f]
inclination is:61.1° ± 0.3° [B18f]
ascending node Ωs:139.6° ± 0.2° [B18f]
mean anomaly M:273.2° ± 0.02° [B18f]
Epoch:2015 Feb 01.95
normalized ang. mom. αL: ?

other data, system (combined):
absolute mag. H: -1.2 [MPC]
-1.12 ± 0.03 [S12a]
slope parameter G: (0.15) [*A]
effective diameter dE: 2380 km [*D]
geometric albedo: 0.96 ± 0.09/0.04 [S11a]
color index U-B: ?
color index B-V: 0.823 [C06c]
color index V-R:0.391 ± 0.023 [C06c]
color index B-R:1.214 [C06c]
color index V-I:0.777 ± 0.013 [C06c]
color index R-J:0.56 [B05c]
color index J-H:-0.29 [B05c]
taxonomic type: BB (G-mode) [P10a]
mass m: 1.66x1022 ± 2x1020 kg [B07c]
density ρ: 2.52 ± 0.05/0.05 g/cm3[S11a]
Hill radius rH: 8000000 km [*D]

other data, primary:
diameter dp: 2326 ± 12 km [S11a]
rotation period RPp: 378.6 h [R14a]
amplitude in mag., rotational ΔM: 0.1 [R08a]
pole direction Β, λ: ? , ?


other data, secondary:
diameter ds: 700 ± 115 km [B18f]
diameter ratio ds/dp: 0.301 ± 0.05 [B18f]
component mag. difference ΔM: 4.43 ± 0.05 [I8610]
geometric albedo :0.04± 0.02[0.01]
rotation period RPs: ?

-- (136199) Eris and Dysnomia --discovery and notes:

Primary discovered 2003 Oct 21 from Palomar Observatory, California, USA by M. E. Brown, C. A. Trujillo, and D. L. Rabinowitz. Alternate designation(s): 2003 UB313 . Linked to prediscovery observations from 1954 Sep 03. Permanent number assigned 2006 Sep 07.

Named 2006 Sep 14 for the mythological Greek goddess of discord [MPC057800].

Companion discovered 2005 Sep 10 by M. E. Brown, et al. using adaptive optics telescope observations from W. M. Keck II Telescope, Mauna Kea, Hawaii, USA. Announced 2005 Oct 02 [B05d]. Provisional designation S/2005 (2003 UB313) 1. Permanent designation I Dysnomia, assigned 2006 Sep 14; named for the Greek mythological spirit of lawlessness [G06d].

--Links, more technical:

--Links, less technical:

--Links to ADS abstracts:


© 2005-2014, 2018 by Wm. Robert Johnston.
Last modified 23 September 2018.
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