Asteroids with Satellites Database--Johnston's Archive

(69230) Hermes

compiled by Wm. Robert Johnston
last updated 11 May 2014
under construction--testing upgrades!

--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: NEA, Apollo (PHA)


orbital data, primary (osculating elements) [JPL] :
semimajor axis a: 1.655109415 AU
orbital period P: 2.129355952 yr (= 777.7472616 d)
eccentricity e: 0.624135010
perihelion distance q: 0.622097684 AU
aphelion distance Q: 2.688121147 AU
inclination i: 6.0682380°
argument of perihelion ω: 92.7131629°
ascending node Ω: 34.2429732°
mean anomaly M: 320.3225723°
perihelion passage TP: 2014 Aug 16.719474
Epoch: 2014 May 23
data arc: 1937-2011 (827 obs.)
Earth MOID: 0.00428968 AU
Jupiter Tisserand invariant TJ: 4.02


orbital data, secondary:
binary dynamical type:B [P07f]
semimajor axis as: 1.1 km [*E]
separation/primary radius as/rp:3.7 [*E]
separation/Hill radius as/rH:0.032 [*E]
orbital period Ps: 0.5789 ± 0.00017 d [P06b]
eccentricity es: ?
normalized ang. mom. αL: 1.22 [P07f]

other data, system (combined):
absolute mag. H: 17.5 [MPC]
17.55 ± 0.1 [I8233]
slope parameter G: 0.15 [*A]
effective diameter dE: 0.81 km [*D]
geometric albedo: 0.25 ± 0.12 [P06b]
color index U-B: ?
color index B-V: ?
taxonomic type: ?
mass m: ?
density ρ: 1.6 g/cm3 [*A]
Hill radius rH: 35 km [*E]

other data, primary:
diameter dp: 0.6 ± 0.12 km [P06b]
rotation period RPp: 13.894 ± 0.004 h [P06b]
amplitude in mag., rotational ΔM: ?
pole direction : ? ; ?


other data, secondary:
diameter ds: 0.54 ± 0.12 km [*D]
diameter ratio ds/dp: 0.9 ± 0.09 [P06b]
component mag. difference ΔM: ?
rotation period RPs: 13.892 ± 0.006 h [I8233]

-- (69230) Hermes --discovery and notes:

Primary discovered 1937 Oct 28 from Heidelberg, Germany by K. Reinmuth. Alternate designation(s): 1937 UB . Linked to prediscovery observations from 1937 Oct 25. Permanent number assigned 2003 Nov 09.

Named 1938 Jan for the mythological Greek messenger of the gods [MPC50255].

Companion discovered 2003 Oct 18 by J. L. Margot, M. C. Nolan, V. Negron, A. A. Hine, D. B. Campbell, E. S. Howell, L. A. M. Benner, S. J. Ostro, and J. D. Giorgini using RAD observations from Arecibo Observatory, Puerto Rico. Announced 2003 Oct 20 [I8227].

--Links, more technical:

--Links, less technical:

--Links to ADS abstracts:


© 2003-2005, 2014 by Wm. Robert Johnston.
Last modified 11 May 2014.
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