| Minorplanet: | yes |
| 1006 Lagrangea | |
| Background: |
|
| Discovered: | 12 September 1923 |
| Mpc Name: | (1006) Lagrangea |
| Alt Names: | 1923 OU |
| Named After: | |
| Epoch: | 4 September 2017 (JD 2458000.5) |
| Uncertainty: | 0 |
| Observation Arc: | 93.73 yr (34,235 days) |
| Perihelion: | 2.0210 AU |
| Semimajor: | 3.1425 AU |
| Eccentricity: | 0.3569 |
| Period: | 5.57 yr (2,035 days) |
| Mean Motion: | / day |
| Inclination: | 10.917° |
| Asc Node: | 294.59° |
| Arg Peri: | 86.231° |
| Dimensions: | 29.53 km km km km km |
| Albedo: | 0.0612 |
| Abs Magnitude: | 11.2011.30 |
Lagrangea (minor planet designation: 1006 Lagrangea), provisional designation, is a carbonaceous background asteroid from the outer region of the asteroid belt, approximately 30 kilometers in diameter. It was discovered on 12 September 1923, by Russian astronomer Sergey Belyavsky at the Simeiz Observatory on the Crimean peninsula. The asteroid was named after Italian mathematician and astronomer Joseph-Louis Lagrange.
Lagrangea is not a member of any known asteroid family. It orbits the Sun in the outer main belt at a distance of 2.0–4.3 AU once every 5 years and 7 months (2,035 days). Its orbit has an eccentricity of 0.36 and an inclination of 11° with respect to the ecliptic. The body's observation arc begins at the discovering observatory, 4 days after its official discovery observation.
Lagrangea has been characterized as a dark D-type asteroid by Pan-STARRS photometric survey, while the LCDB assumes a generic, carbonaceous C-type.
In September 2001, a rotational lightcurve of Lagrangea was obtained from photometric observations by French amateur astronomer Laurent Bernasconi. Lightcurve analysis gave a longer-than-average rotation period of 32.79 hours with a brightness amplitude of 0.17 magnitude. As the lightcurve has received a low quality rating, the obtained period must be considered tentative .
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, Lagrangea measures between 29.56 and 35.31 kilometers in diameter and its surface has an albedo between 0.046 and 0.067.
The Collaborative Asteroid Lightcurve Link derives an albedo of 0.0612 and a diameter of 29.53 kilometers based on an absolute magnitude of 11.3.
This minor planet was named after Italian mathematician Joseph-Louis Lagrange (1736–1813), who made significant contributions to astronomy, in particular celestial mechanics. The official naming citation was mentioned in The Names of the Minor Planets by Paul Herget in 1955 . The Lagrangian points are named after him. He is also honored by the lunar crater Lagrange.