Constraints on Jupiter’s Age and Formation Mechanism and the Nebula Lifetime from Chondrites and Asteroids

Introduct ion: Since the major chondritic components—chondrules, Ca-Al–rich inclusions (CAIs), and amoeboid-olivine inclusions—formed in the nebula, their ages provide a limit for the lifetime of the solar nebula. If chondritic components accreted into asteroids before Jupiter formed, then these ages also provide constraints on the time of Jupiter’s formation. Such constraints might identify whether Jupiter formed rapidly in 10 yr by gravitational instabilities in the nebula [1], or more slowly by core accretion in a few Myr [2]. Comparison of the lifetimes of the solar nebula and protostellar disks and constraints on the formation ages of extrasolar planets may then offer some insights into the origins of extrasolar planets and differences between the orbits of solar and extrasolar planets. Here we focus on constraints on the formation of Jupiter that can be derived from chondrites and asteroids and models for their accretion and the evolution of the asteroid belt. Three questions are addressed: When did the chondritic components form in the solar nebula? What role if any did Jupiter play in the formation of chondritic components? Did Jupiter form before the asteroids accreted?