Vesta and extensively melted asteroids: Why HED meteorites are probably not from Vesta

摘要: Abstract Most researchers hold that the HED clan of differentiated meteorites originated on Vesta largely based assumption nearly all V-type asteroids with basaltic reflection spectra are fragments spalled off Vesta. Although it is a reasonable working hypothesis most in family Vesta, not unique enough to confirm this; sizable fraction may have been produced during destruction asteroid same large region dynamic space. Observations inner Asteroid Belt show more than half do belong family. Iron-meteorite evidence shows at least 26 experienced extensive melting and would generated basalts other stony meteorites. iron high degrees elemental fractionations lead conclusion they fractional crystallization; probable these bodies basalts. There 9 “magmatic” iron-meteorite groups test criteria mainly extreme indicate an additional 17 disrupted hosted fractionally crystallized cores thus ⩾26 melting; this estimate much lower previous estimates included nonmagmatic irons. Within expected planetary heterogeneities O-isotopic composition HEDs as oxides from IIIAB irons, largest magmatic group e Cr 54 values also very similar IIIABs HEDs. The O- Cr-isotopic ties stronger spectral tie should be parent asteroid. Remote analysis could If future remote measures K contents ⩾0.6 mg/g will did originate