Asteroids with Satellites Database--Johnston's Archive

(21527) Horton

compiled by Wm. Robert Johnston
last updated 20 October 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: 2.578635661 AU
orbital period P: 4.1408068835 yr
(= 1512.458279 d)
eccentricity e: 0.183169195
perihelion distance q: 2.10630904 AU
aphelion distance Q: 3.05096228 AU
inclination i: 12.6945139°
argument of perihelion ω: 47.288121°
ascending node Ω: 286.407008°
mean anomaly M: 335.386683°
perihelion passage TP: 2019 Aug 08.407266
Epoch: 2019 Apr 27
data arc: 1951-2019 (1511 obs.)
Earth MOID: 1.11539 AU
Jupiter Tisserand invariant TJ: 3.368


orbital data, secondary:
semimajor axis as: 8.7 km [*E]
separation/primary radius as/rp:3.6 [*E]
separation/Hill radius as/rH:0.011 [*E]
orbital period Ps: 0.7267 ± 0.0004 d [B19e]
eccentricity es: ?
normalized ang. mom. αL: ?

other data, system (combined):
absolute mag. H: 13.3 [MPC]
slope parameter G: (0.15) [*A]
effective diameter dE: 4.99 ± 0.35 km [M**]
geometric albedo: 0.34 ± 0.064 [M**]
color index U-B: ?
color index B-V: ?
taxonomic type: ?
mass m: ?
density ρ: (1.6 g/cm3) [*A]
Hill radius rH: 800 km [*E]

other data, primary:
diameter dp: 4.88 km [*D]
rotation period RPp: 2.76762 ± 0.00011 h [B19e]
amplitude in mag., rotational ΔM: 0.08 [B19e]
pole direction Β, λ: ? , ?


other data, secondary:
diameter ds: >1.02 km [*D]
diameter ratio ds/dp: >0.21 [B19e]
component mag. difference ΔM: <3.4 [*D]
rotation period RPs: ?

-- (21527) Horton --discovery and notes:

Primary discovered 1998 Jun 24 from Socorro, New Mexico, USA by LINEAR Program. Alternate designation(s): 1998 MV27, 1999 XY191. Linked to prediscovery observations from 1951 Jan 04. Permanent number assigned 2001 Feb 08.

Named 2006 Jul 11 for Douglas Ray Horton (1988-) [MPC057275].

Companion discovered 2019 Sep 04 by V. Benishek, P. Pravec, P. Kusnirak, V. Chiorny, D. Pray using lightcurve observations from Sopot Observatory, Serbia; Chuguev station, Kharkiv Observatory, Ukraine; Sugarload Mountain Observatory. Announced 2019 Oct 18 [B19e].

--Links, more technical:

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--Links to ADS abstracts:


© 2019 by Wm. Robert Johnston.
Last modified 20 October 2019.
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