Asteroids with Satellites Database--Johnston's Archive

(3657) Ermolova

compiled by Wm. Robert Johnston
last updated 27 May 2019

--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: 2.3131752293 AU
orbital period P: 3.5181374226 yr
(= 1285.0239628 d)
eccentricity e: 0.132219768
perihelion distance q: 2.007327737 AU
aphelion distance Q: 2.6190227214 AU
inclination i: 5.7899826°
argument of perihelion ω: 102.021739°
ascending node Ω: 237.271168°
mean anomaly M: 330.191176°
perihelion passage TP: 2020 Sep 14.402926
Epoch: 2020 May 31
data arc: 1925-2020 (2634 obs.)
Earth MOID: 1.00844 AU
Jupiter Tisserand invariant TJ: 3.564


orbital data, secondary:
semimajor axis as: 9.4 km [*E]
separation/primary radius as/rp:2.8 [*E]
separation/Hill radius as/rH:0.0091 [*E]
orbital period Ps: 0.5225 ± 0.0001 d [P20d]
eccentricity es: ?
normalized ang. mom. αL: ?

other data, system (combined):
absolute mag. H: 12.7 [MPC]
12.45 ± 0.09 [P20d]
slope parameter G: 0.24 [P20d]
effective diameter dE: 6.66 ± 0.66 km [M**]
geometric albedo: 0.543 ± 0.171 [M**]
color index U-B: ?
color index B-V: ?
taxonomic type: ?
mass m: ?
density ρ: (1.6 g/cm3) [*A]
Hill radius rH: 1000 km [*E]

other data, primary:
diameter dp: 6.6 ± 0.66 km [*D]
rotation period RPp: 2.60655 ± 0.00006 h [P20d]
amplitude in mag., rotational ΔM: 0.2 [P20d]
amplitude in mag., mutual events ΔM:0.025 ±0.005 [P20d]
pole direction Β, λ: ? , ?


other data, secondary:
diameter ds: 0.92 ± 0.22 km [P20d]
diameter ratio ds/dp: 0.14 ± 0.03 [P20d]
component mag. difference ΔM: 4.27 ± 0.47 [*D]
rotation period RPs: ?

-- (3657) Ermolova --discovery and notes:

Primary discovered 1978 Sep 26 from Nauchnyj, Crimea, Ukraine, USSR by L. Zhuravleva. Alternate designation(s): 1978 ST6, 1925 TE, 1984 OD1. Linked to prediscovery observations from 1925 Oct 06. Permanent number assigned 1987 Aug 09.

Named 1993 Jun 04 for Maria Nikolaevna Ermolova (1853-1928) [MPC022246].

Companion discovered 2020 Jul 19 by D. Pray, P. Pravec, P. Kusnirak, H. Kucakova, K. Hornoch, P. Bacci, M. Maestripieri, J. Oey, R. Durkee, A. Marchini, and R. Papini using lightcurve observations from Sugarloaf Mountain Observatory, South Deerfield, Massachusetts, USA; Ondrejov Observatory; San Marcello Pistoiese Observatory, Italy; Blue Mountains Observatory, Leura, New South Wales, Australia; Sopot Observatory, Serbia; Shed of Science South Observatory, Pontotoc, Texas; Astronomical Observatory of the University of Siena. Announced 2020 Sep 28 [P20d].

--Links, more technical:

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--Links to ADS abstracts:


© 2020 by Wm. Robert Johnston.
Last modified 11 October 2020
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