Asteroids with Satellites Database--Johnston's Archive

(3548) Eurybates and S/2018 (3548) 1

compiled by Wm. Robert Johnston
last updated 17 January 2020

--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: Jupiter trojan asteroid, L4


orbital data, primary (osculating elements) [JPL] :
semimajor axis a: 5.19424164 AU
orbital period P: 11.838133235 yr
(= 4323.959834 d)
eccentricity e: 0.088827829
perihelion distance q: 4.73284843 AU
aphelion distance Q: 5.65563485 AU
inclination i: 8.05906926°
argument of perihelion ω: 27.4983765°
ascending node Ω: 43.53792846°
mean anomaly M: 270.9907398°
perihelion passage TP: 2022 Mar 31.090183
Epoch: 2019 Apr 27
data arc: 1997-2019 (2609 obs.)
Earth MOID: 3.74939 AU
Jupiter Tisserand invariant TJ: 2.972


orbital data, secondary:
semimajor axis as: 2000 ± 300 km (separation) [N20a]
separation/primary radius as/rp:63 [*E]
separation/Hill radius as/rH:0.091 [*E]
orbital period Ps: 55 d [*E]
eccentricity es: ?
normalized ang. mom. αL: ?

other data, system (combined):
absolute mag. H: 9.8 [MPC]
slope parameter G: (0.15) [*A]
effective diameter dE: 63.88 ± 0.3 km [M**]
geometric albedo: 0.052 ± 0.007 [M**]
color index U-B: ?
color index B-V: 0.677 [H12d]
color index V-R:0.352 ± 0.045 [H12d]
color index V-I:0.691 ± 0.05 [H12d]
taxonomic type: ?
mass m: ?
density ρ: (1 g/cm3) [*A]
Hill radius rH: 22000 km [*E]

other data, primary:
diameter dp: 63.88 ± 0.3 km [M**]
rotation period RPp: 8.711 ± 0.009 h [JPL]
amplitude in mag., rotational ΔM: ?
pole direction Β, λ: ? , ?


other data, secondary:
diameter ds: 0.8 ± 0.2 km [N20a]
diameter ratio ds/dp: 0.013 [*D]
component mag. difference ΔM: >9.4 [H20a]
rotation period RPs: ?

-- (3548) Eurybates and S/2018 (3548) 1 --discovery and notes:

Primary discovered 1973 Sep 19 from Palomar Observatory, California, USA by C. J. Van Houten, I. Van Houten-Groenveld, and T. Gehrels. Alternate designation(s): 1973 SO, 1954 CB, 1957 JX, 1978 EE5, 1985 TZ. Linked to prediscovery observations from 1954. Permanent number assigned 1987 Feb 13.

Named 1991 Apr 28 for the Greek army herald [MPC018138].

Companion discovered 2018 Sep 12 by K. S. Noll, M. E. Brown, H. A. Weaver, W. M. Grundy, H. F. Levison, C. Olkin, S. B. Porter, M. W. Buie, J. R. Spencer, S. Marchi, and T. Statler using Hubble Space Telescope observations from Hubble Space Telescope. Announced 2020 Jan 09 [N20a]. Provisional designation S/2018 (3548) 1.

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--Links to ADS abstracts:


© 2020 by Wm. Robert Johnston.
Last modified 17 January 2020.
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