Asteroids with Satellites Database--Johnston's Archive

(38079) 1999 HF

compiled by Wm. Robert Johnston
last updated 9 August 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: main belt asteroid


orbital data, primary (osculating elements) [JPL] :
semimajor axis a: 2.3239710619 AU
orbital period P: 3.5427954143 yr
(= 1294.0304644 d)
eccentricity e: 0.191858478
perihelion distance q: 1.87809751 AU
aphelion distance Q: 2.769844614 AU
inclination i: 24.1393873°
argument of perihelion ω: 2.868655°
ascending node Ω: 182.2930465°
mean anomaly M: 16.4959645°
perihelion passage TP: 2020 Apr 01.704776
Epoch: 2020 May 31
data arc: 1993-2020 (1663 obs.)
Earth MOID: 0.880853 AU
Jupiter Tisserand invariant TJ: 3.436


orbital data, secondary:
semimajor axis as: ?
orbital period Ps: ?
eccentricity es: ?
normalized ang. mom. αL: ?

other data, system (combined):
absolute mag. H: 14.3 [MPC]
slope parameter G: (0.15) [*A]
effective diameter dE: 3.42 ± 0.12 km [M*]
geometric albedo: 0.287 ± 0.07 [M*]
color index U-B: ?
color index B-V: ?
taxonomic type: ?
mass m: ?
density ρ: (1.6 g/cm3) [*A]
Hill radius rH: 500 km [*E]

other data, primary:
diameter dp: 3.42 ± 0.12 km [M*]
rotation period RPp: 16.675 h [W20b]
amplitude in mag., rotational ΔM: 0.42 [W20b]
pole direction Β, λ: ? , ?


other data, secondary:
diameter ds: ?
diameter ratio ds/dp: ?
component mag. difference ΔM: ?
rotation period RPs: ?

-- (38079) 1999 HF --discovery and notes:

Primary discovered 1999 Aor 16 from Xinglong, PR China by BAO Schmidt CCD Asteroid Program. Alternate designation(s): 1993 SY7. Linked to prediscovery observations from 1993 Sep 17. Permanent number assigned 2002 Mar 28.

Companion discovered 2020 using lightcurve observations. Announced 2020 Jun 11.

--Links, more technical:

--Links, less technical:

--Links to ADS abstracts:


© 2020 by Wm. Robert Johnston.
Last modified 9 August 2020.
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