|Discovery site||Mount Lemmon Obs.|
|Discovery date||31 December 2007|
|(456938) 2007 YV56|
|NEO · Apollo · PHA|
|Epoch 23 March 2018 (JD 2458200.5)|
|Uncertainty parameter 0|
|Observation arc||8.10 yr (2,959 days)|
|1.98 yr (722 days)|
|0° 29m 54.24s / day|
|Earth MOID||0.0047 AU (1.83 LD)|
|Venus MOID||0.0019 AU|
|Mars MOID||0.0571 AU|
|0.19 km (est. at 0.20)|
0.36 km (est. at 0.057)
(456938) 2007 YV56, provisional designation 2007 YV56, is a sub-kilometer asteroid on an eccentric orbit, classified as a near-Earth object and potentially hazardous asteroid of the Apollo group, approximately 190–360 meters (620–1,200 ft) in diameter. It was discovered on 31 December 2007, by astronomers of the Catalina Sky Survey conducted at the Catalina Station in Arizona, United States.
It orbits the Sun at a distance of 0.60–2.55 AU once every 2 years (722 days; semi-major axis of 1.58 AU). Its orbit has a high eccentricity of 0.62 and an inclination of 6° with respect to the ecliptic. This makes it also a Mars-crossing asteroid, as it crosses the orbit of the Red Planet at 1.66 AU, as well as a Venus-crosser due to its aphelion of less than 0.71 AU. The body's observation arc begins at Catalina with its official discovery observation in December 2007.
2007 YV56 has a minimum orbital intersection distance (MOID) with Earth of 703,000 km; 437,000 mi (0.0047 AU), which corresponds to 1.83 lunar distances (LD). It has an absolute magnitude of 21.0. This makes it a potentially hazardous asteroid, which are defined as having a MOID of less than 0.05 AU (19 LD) and an absolute magnitude brighter than 22. Besides Earth, it also makes close approaches to Venus, Mars and the Moon.
On 26 December 2007, five days prior to its discovery observation, it passed Earth at a nominal distance of 0.10037 AU (39.06 LD). On 2 January 2101, it is predicted to flyby Earth at 0.00159 AU (0.62 LD) and pass the Moon at a similar distance five hours earlier as well (also see List of asteroid close approaches to Earth § Predicted encounters).
Based on a generic magnitude-to-diameter conversion, 2007 YV56 measures 190–360 meters (620–1,180 ft) in diameter, for an absolute magnitude of 21.0, and an assumed albedo of 0.20 and 0.057, which represent typical values for stony and carbonaceous asteroids, respectively.