702 Alauda

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702 Alauda
702 Alauda as seen an hour after occulting TYC 1920-00620-1[1]
Discovered by Joseph Helffrich
Discovery date 16 July 1910
Pronunciation /əˈlɔːdə/ ə-LAW-də
1910 KQ
Main belt
Orbital characteristics[2]
Epoch June 18, 2009 (2455000.5)
Aphelion 3.2614 AU (Q)
Perihelion 3.1238 AU (q)
3.1926 AU (a)
Eccentricity 0.02155
5.70 yr
149.62° (M)
Inclination 20.612°
Known satellites Pichi üñëm[3]
Physical characteristics
Dimensions 195±3 km[2]
Mass (6.057 ± 0.36)×1018 kg[4]
Mean density
(1.57 ± 0.5) g/cm³[4]
Albedo 0.0587[2]
Spectral type
11.42 to 13.57[5]

702 Alauda is a large asteroid 195±3 km in diameter.[2] It was discovered in 1910 by Joseph Helffrich from the observatory at Heidelberg University. It is named after the lark (alauda). In 2007, a small moon, named Pichi üñëm, was discovered.


Alauda's satellite Pichi üñëm (provisionally known as S/2007 (702) 1) was discovered from observations using adaptive-optics imaging with the European Southern Observatory (ESO) 8-m Very Large Telescope (VLT) on Cerro Paranal, Chile.[3] It is 5.5 km in diameter and has a projected separation from Alauda of 900 km.[6][7] It was named Pichi üñëm, meaning "little bird" in the Mapuche language of Chile, the country from which the moon was discovered.[8]

Orbital characteristics[edit]

Alauda has been identified as the largest member of a dynamical family.[3] 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.[9] Alauda's moon may be a result of the collision that created the asteroid family.[3]

Physical characteristics[edit]

The discovery of Alauda's moon enabled Alauda's mass to be determined. Rojo and Margot (2010) have estimated its mass to be 6.06×1018 kg with a density of 1.57 g/cm³.[4]


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.[10] 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]


  1. ^ a b c Steve Preston. "(702) Alauda / TYC 1920-00620-1 event on 2009 Oct 17, 08:18 UT". Asteroid Occultation Updates. Retrieved 2009-10-05. 
  2. ^ a b c d e f g "JPL Small-Body Database Browser: 702 Alauda (1910 KQ)" (2009-02-15 last obs). Retrieved 2009-10-06. 
  3. ^ a b c d Margot, Jean-Luc; Rojo, P. (2007). "Discovery of a Satellite to Asteroid Family Member (702) Alauda". American Astronomical Society 39: 440. Bibcode:2007DPS....39.1608M. 
  4. ^ a b c Rojo, P.; Margot, J. L. (2010). "Mass and Density of the B-type Asteroid (702) Alauda". The Astrophysical Journal 727 (2): 69. arXiv:1011.6577. Bibcode:2011ApJ...727...69R. doi:10.1088/0004-637X/727/2/69. 
  5. ^ Magnitudes generated with JPL Horizons for the year 1950 through 2100
  6. ^ Daniel W. E. Green (2007-08-02). "Electronic Telegram No. 1016". IAU Central Bureau for Astronomical Telegrams. Retrieved 2011-07-05. 
  7. ^ "Asteroid and Dwarf Planet News". Retrieved 2009-10-06. 
  8. ^ New Names of Minor Planets PDF (2.19 MB)
  9. ^ "Opposition dates and magnitudes for 702 family members (2004–2008)". Italian organization of minor planet observers. Retrieved 2009-10-05. 
  10. ^ David Dunham. "Observed asteroidal occultation list". Retrieved 2011-01-27. 

External links[edit]