1221 Amor/ˈæmɔːr/ is anasteroid andnear-Earth object on an eccentric orbit, approximately 1 kilometer (0.6 miles) in diameter. It is the namesake of theAmor asteroids, the second-largest subgroup of near-Earth objects. It was discovered byEugène Delporte at theUccle Observatory in 1932, the first time that an asteroid was seen to approach Earth so closely.[1] The assumedS-type asteroid is one of fewlow-numbered asteroids for which norotation period has been determined.[8] It was assigned the provisional designation1932 EA1 and named forCupid, also known as "Amor" in Latin, the Roman equivalent of the Greek godEros.[4]
Amor is the namesake of theAmor asteroid, a subgroup ofnear-Earth asteroids that approach the orbit of Earth from beyond, but do notcross it. Next to theApollo group, the Amors are the second largest group of near-Earth objects with more than 7,000 known members.[10] As with many members of this group,Amor is also aMars-crosser, crossing the orbit of the Red Planet at 1.66 AU.[6]
It orbits the Sun at a distance of 1.08–2.76 AU once every 2 years and 8 months (971 days;semi-major axis of 1.92 AU). Its orbit has a higheccentricity of 0.44 and aninclination of 12° with respect to theecliptic.[6]
Amor has an Earthminimum orbital intersection distance of 0.1069 AU (16,000,000 km) which corresponds to 41.6lunar distances.[6] In March 1940, it approached Earth to 0.1052 AU (15,700,000 km), its closest approach of all close encounters since 1900. Only in March 2129, it will approach Earth at a similar distance of 0.1082 AU (16,200,000 km).[6]
According toTom Gehrels's publicationHazards due to Comets and Asteroids from 1994 (pp. 540–543),Amor measures 1.0 kilometer in diameter and its surface has analbedo of 0.15.[6] TheCollaborative Asteroid Lightcurve Link assumes a standard albedo for stony asteroids of 0.20 and calculates a diameter of 0.857 kilometers based on anabsolute magnitude of 17.7.[8]