Title: Rivers in the sky: streamers discovered towards two young embedded protostars in Perseus

Abstract: In the last few years, there has been a rise in the discovery of streamers, which are long gas structures (~ 1000-10000 au) that feed the protostellar disk and/or pseudodisk region with material from both within and outside their natal core. This newly observed infall mechanism goes against the classical picture of star formation, where accretion into the protostar and protoplanetary disk is azimuthally symmetric and relatively isolated from external influences. Streamers have been found in multiple phases of star formation, from the deeply embedded protostars to unveiled protoplanetary disks. In this talk, I will present our current knowledge of streamers and present two new members to our collection, found toward young embedded protostars using ALMA and NOEMA observations. I will show how we characterise the gas kinematic signatures with a simple analytic solution for free-fall motion. It is only thanks to the combination of several tracers that enables for a better understanding of the mass delivery process to disk scales. I will finally discuss the possible effects of these streamers in protostellar disks and how they could connect to the large-scale filaments and fibers. These newfound streamers and asymmetries in the dense core highlight the importance of the local environment even in later stages of star formation.