(2491) Tvashtri

--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, Hungaria orbital data, primary (osculating elements) [JPL] : semimajor axis a: 1.8776230116 AU orbital period P: 2.5728389319 yr (= 939.7471681 d) eccentricity e: 0.054172476 perihelion distance q: 1.775907524 AU aphelion distance Q: 1.9793384988 AU inclination i: 22.866198° argument of perihelion ω: 357.912752° ascending node Ω: 125.309799° mean anomaly M: 30.552926° perihelion passage TP: 2018 Jan 02.24437 Epoch: 2018 Mar 23 data arc: 1977-2018 (1394 obs.) Earth MOID: 0.790968 AU Jupiter Tisserand invariant TJ: 3.877 orbital data, secondary: semimajor axis as: 7.5 km [*E] separation/primary radius as/rp: 4.7 [*D] separation/Hill radius as/rH: 0.016 [*D] orbital period Ps: 1.113 ± 0.0002 d [W18b] eccentricity es: ? normalized ang. mom. αL: ?

other data, system (combined): absolute mag. H: 13.68 [MPC] slope parameter G: (0.15) [*A] effective diameter dE: 3.26 ± 0.08 km [M11b] geometric albedo: 0.561 ± 0.207 [M11b] color index U-B: 0.261 [JPL] color index B-V: 0.756 [JPL] taxonomic type: X (Tholen) [JPL] mass m: ? density ρ: (1.6 g/cm3) [*A] Hill radius rH: 460 km [*E] other data, primary: diameter dp: 3.17 km [*D] rotation period RPp: 4.0852 ± 0.0002 h [W18b] amplitude in mag., rotational ΔM: 0.08 ± 0.01 [W18b] amplitude in mag., mutual events ΔM: 0.085 ±0.03 [W18b] pole direction Β, λ: ? , ? other data, secondary: diameter ds: >0.76 km [*D] diameter ratio ds/dp: >0.24 ± 0.02 [W18a] component mag. difference ΔM: >3.1 [*D] rotation period RPs: ?