2114 Wallenquist, provisional designation 1976 HA, is a Themistian asteroid from the outer region of the asteroid belt, approximately 28 kilometers in diameter. It was discovered by Swedish astronomer Claes-Ingvar Lagerkvist at the Australian Mount Stromlo Observatory near Canberra, on 19 April 1976.
Orbit and classification
Wallenquist is a member of the Themis family, a dynamical family of outer-belt asteroids with nearly coplanar ecliptical orbits. It orbits the Sun in the outer main-belt at a distance of 2.7–3.7 AU once every 5 years and 9 months (2,090 days). Its orbit has an eccentricity of 0.14 and an inclination of 1 ° with respect to the ecliptic. The first used observation was made at the U.S.  Goethe Link Observatory in 1953, extending the asteroid's observation arc by 23 years prior to its discovery.
In April 2010, a rotational
lightcurve of Wallenquist obtained by American astronomer Robert Stephens at the Goat Mountain Astronomical Research Station (GMARS, ), California, gave a well-defined G79 rotation period of hours with a brightness amplitude of 0.22 5.510 magnitude ( ). U=3
Two other observations, by French astronomer
René Roy at Blauvac Observatory ( ), France, and by astronomers at the U.S. 627 Palomar Transient Factory, gave a period of and 5.49 ±0.01 , with an amplitude of 0.30 and 0.23, respectively ( 5.5078 ±0.0009 ). U=2/2 
Diameter and albedo
According to the surveys carried out by the Infrared Astronomical Satellite,
IRAS, the Japanese Akari satellite, and the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, Wallenquist measures between 21.1 and 27.6 kilometers in diameter while its surface has an albedo in the range of 0.08 and 0.15.   
Collaborative Asteroid Lightcurve Link (CALL) derives an even lower albedo of 0.04 and calculates a diameter of 27.5 kilometer. Despite its low albedo, CALL characterizes the body as a S-type rather than a darker C-type asteroid.
minor planet was named in honor of Swedish astronomer Åke Wallenquist (1904–1994), former director of the Kvistaberg Station, after which the minor planet 3331 Kvistaberg is named.
After his retirement Wallenquist continued to research
dark matter in open clusters at the Uppsala Astronomical Observatory. He co-discovered the near-Earth Amor asteroid 1980 Tezcatlipoca during his stay at the Palomar Observatory in California in 1950. The official naming citation was published by the  Minor Planet Center before November 1977 ( ). M.P.C. 4645
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Behrend, Raoul. "Asteroids and comets rotation curves – (2114) Wallenquist". Geneva Observatory . Retrieved . 4 July 2016
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Waszczak, Adam; Chang, Chan-Kao; Ofek, Eran O.; Laher, Russ; Masci, Frank; Levitan, David; et al. (September 2015). "Asteroid Light Curves from the Palomar Transient Factory Survey: Rotation Periods and Phase Functions from Sparse Photometry". The Astronomical Journal. 150 (3): 35. arXiv: . 1504.04041 Bibcode: 2015AJ....150...75W. doi: 10.1088/0004-6256/150/3/75 . Retrieved . 4 July 2016
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