Protostellar winds and chondritic meteorites - Formation of solids: The first step

We discuss the interaction between the magnetosphere of a young star and it s surrounding accretion disk. We consider how an X-wind can be driven magne tocentrifugally from the inner edge of the disk where accreting gas is dive rted onto stellar field lines either to flow onto the Sun or to be flung ou twards with the wind. The X-wind satisfies many observational tests concern ing optical jets, Herbig-Haro objects, and molecular outflows. Connections may exist between primitive solar system materials and X-winds. Chondrules and calcium-aluminum-rich inclusions (CAIs) experienced short melting event s uncharacteristic of the asteroid belt where meteorites originate. The inn er edge of the solar nebula has the shortest orbital timescale available to the system, a few days. Protosolar flares introduce another timescale, ten s of minutes to hours. CAIs may form when solids are lifted from shaded por tions of the disk close to the Sun and are exposed to its intense light for a day or so before they are flung by the X-wind to much larger distances. Chondrules were melted, perhaps many times, by flares at larger distances f rom the Sun before being launched and annealed, but not remelted, in the X- wind. Aerodynamic sorting explains the narrow range of sizes with which CAI s and chondrules are found in chondritic meteorites. Flare-generated cosmic -rays may induce spallation reactions that produce some of the short-lived radioactivities associated with primitive solar system rocks.