1153 Wallenbergia

1153 Wallenbergia, provisional designation, is a stony Florian asteroid from the inner regions of the asteroid belt, approximately 8 kilometers in diameter. It was discovered on 5 September 1924, by Soviet astronomer Sergey Belyavsky at the Simeiz Observatory on the Crimean peninsula. The asteroid was named after German mathematician Georg Wallenberg.

Orbit and classification
Wallenbergia is a member of the Flora family (402), a giant asteroid family and the largest family of stony asteroids in the main-belt. It orbits the Sun in the inner main-belt at a distance of 1.8–2.5 AU once every 3 years and 3 months (1,189 days). Its orbit has an eccentricity of 0.16 and an inclination of 3° with respect to the ecliptic.

The body's observation arc begins with its identification as at Johannesburg Observatory in April 1930, almost six years after its official discovery observation at Simeiz.

Physical characteristics
Wallenbergia has been characterized as a stony S-type asteroid by PanSTARRS photometric survey.

Rotation period
In September 1989, the first rotational lightcurve of Wallenbergia was obtained from photometric observations by Polish astronomer Wiesław Z. Wiśniewski at University of Arizona. Lightcurve analysis gave a well-defined rotation period of 4.096 hours with a brightness amplitude of 0.33 magnitude (U=3). Observations in the R-band at the Palomar Transient Factory in 2014, gave a period of 4.116 and 4.12 hours with an amplitude of 0.25 and 0.23 magnitude, respectively (U=2/2).

Diameter and albedo
According to the survey carried out by the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, Wallenbergia measures 8.02 and 8.037 kilometers in diameter and its surface has an albedo of 0.37 and 0.433, respectively.

The Collaborative Asteroid Lightcurve Link assumes an albedo of 0.24 – taken from 8 Flora, the parent body of the Flora family – and derives a diameter of 9.36 kilometers based on an absolute magnitude of 12.31.

Naming
This minor planet was named after German mathematician Georg Wallenberg (1864–1924). The official naming citation was mentioned in The Names of the Minor Planets by Paul Herget in 1955 (H 107).