| Minorplanet: | yes |
| 2056 Nancy | |
| Background: |
|
| Discovery Ref: |   |
| Discovered: | 15 October 1909 |
| Mpc Name: | (2056) Nancy |
| Alt Names: | A909 TB1929 VQ 1962 XE |
| Named After: | |
| Mp Category: | main-belt   background  |
| Orbit Ref: |   |
| Epoch: | 23 March 2018 (JD 2458200.5) |
| Uncertainty: | 0 |
| Observation Arc: | 108.60 yr (39,665 d) |
| Perihelion: | 1.9098 AU |
| Semimajor: | 2.2175 AU |
| Eccentricity: | 0.1388 |
| Period: | 3.30 yr (1,206 d) |
| Mean Motion: | / day |
| Inclination: | 3.9361° |
| Asc Node: | 225.77° |
| Arg Peri: | 145.80° |
| Mean Diameter: | 10.30 km |
| Albedo: | 0.20 |
| Spectral Type: | SMASS S  |
| Abs Magnitude: | 12.3 12.62 |
2056 Nancy, provisional designation , is a stony background asteroid from the inner regions of the asteroid belt, approximately 10km (10miles) in diameter. It was discovered on 15 October 1909, by German astronomer Joseph Helffrich at Heidelberg Observatory in southwest Germany. The S-type asteroid has a tentative rotation period of 15.0 hours. It was named for Nancy Marsden, wife of British astronomer Brian G. Marsden.
Nancy is a non-family asteroid of the main belt's background population. It orbits the Sun in the inner asteroid belt at a distance of 1.9–2.5 AU once every 3 years and 4 months (1,206 days; semi-major axis of 2.22 AU). Its orbit has an eccentricity of 0.14 and an inclination of 4° with respect to the ecliptic. The asteroid's observation arc begins with its official discovery observation at Heidelberg in October 1909.
This minor planet was named after Nancy Lou Zissell Marsden, wife of British astronomer Brian G. Marsden, who established the asteroid's identification, and after whom another minor planet, 1877 Marsden, was previously named. The official was published by the Minor Planet Center on 1 April 1978 .
Nancy is a common S-type asteroid in the SMASS classification.
As of 2018, only a single fragmentary lightcurve of Nancy has been obtained from photometric observation. Analysis of the rotational lightcurve gives a period of 15 hours with a brightness variation of 0.08 magnitude .
According to the survey carried out by the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, Nancy measures between 7.783 and 11.19 kilometers in diameter and its surface has an albedo between 0.16 and 0.351. The Collaborative Asteroid Lightcurve Link assumes a standard albedo for stony asteroids of 0.20 and calculates a diameter of 10.30 kilometers based on an absolute magnitude of 12.3.