1994 WR12 is an asteroid and near-Earth object approximately 130 meters (430 feet) in diameter.[3][4] As a member of the Aten group almost all of its orbit is closer to the Sun than Earth is. On 24 November 1994 it passed about 374100 km from the Moon.[3] First imaged at Kitami Observatory on 26 November 1994,[1] it was discovered two nights later by American astronomer Carolyn S. Shoemaker at Palomar Observatory on 28 November 1994.[2] The asteroid then went unobserved from 1994 until it was recovered by Mauna Kea in March 2016.[1] It was removed from the Sentry Risk Table on 2 April 2016.[5]
1994 WR12 orbits the Sun at a distance of 0.5–1.1 AU once every 8 months (240 days). Its orbit has an eccentricity of 0.40 and an inclination of 7° with respect to the ecliptic.[3]
It has an Earth minimum orbital intersection distance of 0.0018 AU (269,000 km), which translates into 0.7 lunar distances.[3] On 25 November 2046, it will pass 1633719 km from Earth with an uncertainty of ±4133 km.[3] While listed on the Sentry Risk Table the range for the 2046 close approach distance varied from 0.001 AU (150,000 km) to 0.039 AU (5,800,000 km) from Earth.[8]
While listed on the Sentry Risk Table,[9] virtual clones of the asteroid that fit the uncertainty in the known trajectory showed 116 potential impacts between 2054 and 2109.[4] It had about a cumulative 1 in 9090 chance of impacting the Earth.[4] The formerly poorly known trajectory of this asteroid was further complicated by close approaches to Venus and Mercury.[3] It was recovered by Mauna Kea in March 2016,[1] which extended the observation arc from 34 days to 21 years.
It is estimated that an impact would produce the equivalent of 77 megatons of TNT,[4] roughly 1.5 times that of most powerful nuclear weapon ever detonated (Tsar Bomba).
It has too a unique characteristic: it's complanar with Mercury, it can to be a fragment thrown away by an asteroid impact on Mercury, it's very little MOID with the Earth can produce a meteor shower on Earth and if the meteoroids were large enough even Mercurian meteorites.