2023RNAAS...7..204C

During the earliest phases of the formation of a Sun-like star, jets play a key role in removing angular momentum from the accretion disk, allowing accretion onto the central star. Here we report, for the first time, the bipolar fast (∼150 km s^–1) jet driven by the archetypical HH 212, as imaged on scales of ∼100 au by CO(6-5). Adopting Local Thermodynamic Equilibrium conditions, and optically thin emission, we derive the total CO column densities in the jet lobes: ∼10¹⁷ cm^–2. Both jet lobes are 1200 au long. The observations have been performed using the ALMA Early Science operations, showing how the ALMA interferometer can be efficiently used in its Band 9 (>600 GHz) to investigate of protostellar jet.