Asteroids with Satellites Database--Johnston's Archive

2015 RJ277

compiled by Wm. Robert Johnston
last updated 9 October 2021

--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: 46.992 AU
orbital period P: 322.14 yr
(= 117662 d)
eccentricity e: 0.20627
perihelion distance q: 37.299 AU
aphelion distance Q: 56.685 AU
inclination i: 5.5038°
argument of perihelion ω: 69.67°
ascending node Ω: 350.0433°
mean anomaly M: 332.354°
perihelion passage TP: 2046 Mar 28
Epoch: 2021 Jul 01
data arc: 2014-2017 (43 obs.)
Earth MOID: 36.3154 AU
Jupiter Tisserand invariant TJ: 5.965
Neptune Tisserand invariant TN:3.075 [*D]


orbital data, secondary:
semimajor axis as: 1100 km (separation) [F21a]
separation/primary radius as/rp:15.4 [*E]
separation/Hill radius as/rH:0.0024 [*E]
orbital period Ps: 8.1 d [*E]
eccentricity es: ?
normalized ang. mom. αL: ?

other data, system (combined):
absolute mag. H: 7.3 [MPC]
6.59 [P20g]
slope parameter G: (0.15) [*A]
effective diameter dE: 153 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: 450000 km [*E]

other data, primary:
diameter dp: 143 km [*E]
rotation period RPp: ?
amplitude in mag., rotational ΔM: ?
pole direction Β, λ: ? , ?


other data, secondary:
diameter ds: 53 km [*E]
diameter ratio ds/dp: 0.37 [*D]
component mag. difference ΔM: 2.17 [P20g]
rotation period RPs: ?

-- 2015 RJ277 --discovery and notes:

Primary discovered 2015 Sep 09 from Mauna Kea Observatory, Hawaii, USA by Outer Solar System Origins Survey. Linked to prediscovery observations from 2014 Nov 21.

Companion discovered 2019 Oct 05 by A. H. Parker, et al., and the Solar System Origins Legacy Survey using Hubble Space Telescope observations from Hubble Space Telescope. Announced 2021 Mar 31 [F21a].

--Links, more technical:

--Links, less technical:

--Links to ADS abstracts:


© 2021 by Wm. Robert Johnston.
Last modified 9 October 2021.
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