1280 Baillauda

1280 Baillauda, provisional designation, is a dark background asteroid from the outermost region of the asteroid belt, approximately 52 kilometers in diameter. Discovered by Eugène Delporte at Uccle Observatory in 1933, the asteroid was named after French astronomer Jules Baillaud.

Discovery
Baillauda was discovered by Belgian astronomer Eugène Delporte at the Royal Observatory of Belgium in Uccle on 18 August 1933. On the following night, it was independently discovered by Soviet astronomer Grigory Neujmin at Simeiz Observatory on the Crimean peninsula. The Minor Planet Center only recognizes the first discoverer.

The asteroid was first identified as at Heidelberg Observatory in April 1912. The body's observation arc begins with its official discovery observation at Uccle in August 1933.

Orbit and classification
Baillauda is a non-family asteroid from the main belt's background population. It orbits the Sun in the outer asteroid belt at a distance of 3.2–3.6 AU once every 6 years and 4 months (2,304 days; semi-major axis of 3.41). Its orbit has an eccentricity of 0.05 and an inclination of 6° with respect to the ecliptic.

Physical characteristics
In the Tholen classification, Baillauda is an X-type asteroid. The Lightcurve Data Base amends this Tholen spectral type and derives a primitive P-type based on the asteroid's low albedo (see below).

Rotation period
In August 1990, a rotational lightcurve of Baillauda was obtained from photometric observations by Swedish astronomer Claes-Ingvar Lagerkvist in a collaboration with other European astronomers. The observations were taken with the 1.5-meter telescope at the Loiano Observatory in Italy (598). Lightcurve analysis gave a rotation period of 12.6 hours with a brightness amplitude of 0.25 magnitude (U=2).

Diameter and albedo
According to the surveys carried out by the Infrared Astronomical Satellite IRAS and the Japanese Akari satellite, Baillauda measures 50.83 and 53.97 kilometers in diameter and its surface has an albedo of 0.0505 and 0.045, respectively. The Collaborative Asteroid Lightcurve Link adopts the results obtained by IRAS, that is an albedo of 0.0505 and a diameter of 50.83 kilometers based on an absolute magnitude of 10.33.

Naming
This minor planet was named after French astronomer Jules Baillaud (1876–1960), who led the Pic du Midi Observatory in the French Pyrenees (1937–1947), after his stay at the observatories at Paris and Lyons (513). Jules was the son of prolific astronomer Benjamin Baillaud (1848–1934), after whom the lunar crater Baillaud was named.

The official naming citation was mentioned in The Names of the Minor Planets by Paul Herget in 1955 (H 117).