Asteroids with Satellites Database--Johnston's Archive

(3390) Demanet

compiled by Wm. Robert Johnston
last updated 11 June 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: main belt asteroid


orbital data, primary (osculating elements) [JPL] :
semimajor axis a: 2.253140014 AU
orbital period P: 3.382067496 yr
(= 1235.3234835 d)
eccentricity e: 0.114882312
perihelion distance q: 1.99429408 AU
aphelion distance Q: 2.5119859484 AU
inclination i: 3.3886456°
argument of perihelion ω: 259.617379°
ascending node Ω: 342.81966°
mean anomaly M: 261.1106422°
perihelion passage TP: 2021 Nov 21.334294
Epoch: 2020 Dec 17
data arc: 1977-2021 (3126 obs.)
Earth MOID: 0.983443 AU
Jupiter Tisserand invariant TJ: 3.614


orbital data, secondary:
semimajor axis as: 14 km [*E]
separation/primary radius as/rp:5.7 [*E]
separation/Hill radius as/rH:0.018 [*E]
orbital period Ps: 1.5475 ± 0.0004 d [B21b]
eccentricity es: ?
normalized ang. mom. αL: ?

other data, system (combined):
absolute mag. H: 13.33 [MPC]
slope parameter G: (0.15) [*A]
effective diameter dE: 5.06 ± 0.26 km [M**]
geometric albedo: 0.274 ± 0.032 [M**]
color index U-B: ?
color index B-V: ?
taxonomic type: ?
mass m: ?
density ρ: (1.6 g/cm3) [*A]
Hill radius rH: 760 km [*E]

other data, primary:
diameter dp: 4.9 ± 0.25 km [*D]
rotation period RPp: 2.59457 ± 0.00003 h [B21b]
amplitude in mag., rotational ΔM: 0.18 [B21b]
amplitude in mag., mutual events ΔM:0.105 ±0.035 [B21b]
pole direction Β, λ: ? , ?


other data, secondary:
diameter ds: 1.27 ± 0.12 km [*D]
diameter ratio ds/dp: 0.26 ± 0.02 [B21b]
component mag. difference ΔM: 2.93 ± 0.17 [*D]
rotation period RPs: ?

-- (3390) Demanet --discovery and notes:

Primary discovered 1984 Mar 02 from La Silla, Chile by H. Debehogne. Alternate designation(s): 1984 ES1, 1977 ED, 1978 QQ, 1982 UF11. Linked to prediscovery observations from 1977 Mar 09. Permanent number assigned 1986 Jan 26.

Named 1989 Dec 12 for the Demanet family name [MPC015573].

Companion discovered 0 by Benishek, V. P. Pravec, and R. Durkee using lightcurve observations. Announced 2021 Apr 24 [B21b].

--Links, more technical:

--Links, less technical:

--Links to ADS abstracts:


© 2021 by Wm. Robert Johnston.
Last modified 11 June 2021.
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