Dust launching and destruction in a protostellar jet: pathway to revealing inner disk refractory budget?

Protostellar outflows and jets are one of the first signposts of new stars being born. I will discuss the revolution brought about by the James Webb Space Telescope (JWST) to the study of these phenomena. I will present the results of the JWST Observations of Young protoStars (JOYS) collaboration, which explores more than 20 protostars in nearby star-forming regions using MIRI-MRS and NIRSpec. Observations of BHR71-IRS1 have revealed a particularly stunning example. The jet shows strong emission lines of refractory species like iron, nickel, and cobalt. At the same time, we detected dust thermal emission, indicating that young jets are dusty and carry away ingredients for planet formation from the inner disk. I will show how jets can be used to understand the composition of those building blocks, especially in the earliest stages of planet formation, when the direct observations of the inner disk are challenging.