(8773) Torquilla

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Asteroid
(8773) Torquilla
Properties of the orbit ( animation )
Epoch:  4th September 2017 ( JD 2,458,000.5)
Orbit type Main outer belt asteroid
Asteroid family Gantrisch family
Major semi-axis 3.1354  AU
eccentricity 0.2201
Perihelion - aphelion 2.4452 AU - 3.8256 AU
Inclination of the orbit plane 8.9115 °
Length of the ascending node 307.5834 °
Argument of the periapsis 124.6865 °
Sidereal period 5.55 a
Mean orbital velocity 16.81 km / s
Physical Properties
Medium diameter 14.583 (± 0.420) km
Albedo 0.044 (± 0.010)
Absolute brightness 13.1 mag
history
Explorer Cornelis Johannes van Houten ,
Ingrid van Houten-Groeneveld ,
Tom Gehrels
Date of discovery September 25, 1973
Another name 5006 T-2 , 1975 BM, 1979 WG 2 , 1981 ED 2
Source: Unless otherwise stated, the data comes from JPL Small-Body Database Browser . The affiliation to an asteroid family is automatically determined from the AstDyS-2 database . Please also note the note on asteroid items.

(8773) Torquilla is an asteroid of the outer main belt , which was discovered on September 25, 1973 by the Dutch astronomer couple Cornelis Johannes van Houten and Ingrid van Houten-Groeneveld . The discovery was made during the 2nd Trojan survey, during which Tom Gehrels surveyed field plates recorded with the 120 cm Oschin Schmidt telescope of the Palomar observatory at the University of Leiden , 13 years after the start of the Palomar-Leiden- Surveys .

The asteroid belongs to the Gantrisch family. The group of asteroids is also called the Lixiaohua family depending on which asteroid is considered to be the larger: (3330) Gantrisch or (3556) Lixiaohua . It is an asteroid family with relatively chaotic orbital parameters seen over a long period of time, since large minor planets in the vicinity of the family (or their orbits around the sun , which intersect the orbits of the family members) such as (1) Ceres , (2) Pallas , (4) Vesta , (10) Hygiea , (52) Europa , (511) Davida and (704) Interamnia influence the orbits of family members and the family is therefore within the sphere of influence of several orbital resonances. The timeless (non- osculating ) orbital elements of (8773) Torquilla are almost identical to those of the smaller one, assuming the absolute brightness of 16.1 compared to 13.0, asteroids (303772) 2005 QS 173 .

According to the SMASS classification ( Small Main-Belt Asteroid Spectroscopic Survey ), a spectroscopic study by Gianluca Masi , Sergio Foglia and Richard P. Binzel at (8773) Torquilla assumed a dark surface, so it could, roughly speaking, be around trade a C asteroid . The albedo of (8773) torquilla was calculated to be 0.044 (± 0.010) and the mean diameter to be 14.583 (± 0.420) km .

(8773) Torquilla is named after the wryneck , a bird in the woodpecker family , whose scientific name is Jynx torquilla . At the time the asteroid was named on February 2, 1999, the wryneck was on the Dutch Red List of Endangered Birds .

Web links

Individual evidence

  1. Bojan Novaković, Kleomenis Tsiganis, Zoran Knežević: Dynamical portrait of the Lixiaohua asteroid family . Celestial Mechanics and Dynamical Astronomy, 2010, # 107, pp. 35–49 ( PDF , English; 1.4 MB)
  2. The family status of the asteroids in the AstDyS-2 database (English, HTML; 51.4 MB)
  3. ^ Gianluca Masi, Sergio Foglia, Richard P. Binzel: Search for Unusual Spectroscopic Candidates Among 40313 minor planets from the 3rd Release of the Sloan Digital Sky Survey Moving Object Catalog . (English)
  4. subdivision of asteroids to S-types, C-types and V-types (English)
  5. ^ Lutz D. Schmadel : Dictionary of Minor Planet Names . Springer, Heidelberg 2012, 6th edition, page 654 (English)