702 Alauda
Main-belt asteroid binary
From Wikipedia, the free encyclopedia
702 Alauda /əˈlɔːdə/, provisional designation 1910 KQ, is a carbonaceous asteroid and binary system from the outer asteroid belt, approximately 190 kilometers in diameter.[2] It is the parent body of the Alauda family. Discovered on 16 July 1910 by German astronomer Joseph Helffrich at Heidelberg Observatory, it was named after the lark (alauda).[3][6] Its small moon, named Pichi üñëm, was discovered in 2007.[10][21]
| |
| Discovery[2][3] | |
|---|---|
| Discovered by | J. Helffrich |
| Discovery site | Heidelberg Obs. |
| Discovery date | 16 July 1910 |
| Designations | |
| (702) Alauda | |
| Pronunciation | /əˈlɔːdə/[4][5] |
Named after | Alauda (genus of Birds)[6] |
| 1910 KQ | |
| main-belt · (outer)[7] Alauda[8] | |
| Adjectives | Alaudian |
| Orbital characteristics[2] | |
| Epoch 4 September 2017 (JD 2458000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 106.89 yr (39,040 days) |
| Aphelion | 3.2533 AU |
| Perihelion | 3.1372 AU |
| 3.1953 AU | |
| Eccentricity | 0.0182 |
| 5.71 yr (2,086 days) | |
| 311.58° | |
| 0° 10m 21.36s / day | |
| Inclination | 20.589° |
| 289.77° | |
| 349.49° | |
| Known satellites | 1 (Pichi üñëm)[9][10] |
| Physical characteristics | |
| Dimensions | 163.98±57.99 km[11] 172.29±55.38 km[12] 175 km[13] 190.58±2.65 km[14] 190.980±1.973 km[15] 194.73±3.2 km[16] 201.961±4.642 km[17] 202±20 km[18] |
| Mass | (6.057±0.36)×1018 kg[19] |
Mean density | 1.57±0.5 g/cm3[19] |
| 8.3531 h (0.34805 d)[7] | |
| 0.0587±0.002[2] | |
| C (Tholen)[2] B (SMASSII)[2] | |
| 11.42 to 13.57[20] | |
| 7.25[2] | |
Satellite
Alauda's satellite Pichi üñëm, provisionally known as S/2007 (702) 1, was discovered on 26 July 2007 from observations using adaptive-optics imaging with the European Southern Observatory (ESO) 8-m Very Large Telescope (VLT) on Cerro Paranal, Chile.[10] It is about 3.5 km in diameter (assuming it has the same albedo as the primary) and orbits Alauda in a nearly circular orbit at a distance of 1226.5±24 km. Pichi üñëm takes 4.91 days to complete one orbit.[19][21][22] It was named Pichi üñëm (Mapudungun: [ˈpɪtʃi ɨˈɲɘm], approximately /ˈpɪtʃi ɪˈnjʌm/), meaning "little bird" in the Mapuche language of Chile, the country from which the moon was discovered.[23]
Orbital characteristics
Alauda has been identified as the largest member of the Alauda family, a dynamical family of bright carbonaceous asteroids with more than a thousand known members.[24]: 23 Other members of this family include: 581 Tauntonia, 1101 Clematis, 1838 Ursa, 3139 Shantou, 3325 TARDIS, 4368 Pillmore, 5360 Rozhdestvenskij, 5815 Shinsengumi, and many others.[25] Alauda's moon may be a result of the collision that created the asteroid family.[10]
Physical characteristics
The discovery and tracking of Alauda's moon enabled Alauda's mass to be determined. The discoverers of the moon, Patricio Rojo and Jean-Luc Margot, estimated Alauda's mass to be (6.057±0.36)×1018 kg and its density to be 1.57±0.5 g/cm3.[19]
Occultations
Alauda has been observed to occult stars on several occasions, providing important information on its size and shape. It produced occultations on 2001-07-12 and 2004-04-21.[26] It may have occulted an apparent magnitude 9.5 star in the constellation of Gemini on 2009-10-17 at 08:18 UT.[1] This event should have been visible from Uruguay, Argentina, and Chile.[1]
