Life on Earth is known to be very diverse. And yet, its basic ingredients are always the same: organic molecules with varying degrees of complexity. Very interestingly, simplified versions of such organic molecules can be observed in regions where stars and planets are forming today in our Galaxy, which can help us understand their chemistry along the different evolutionary phases leading to a star and planetary system like our own. Still, we are far from achieving a full comprehension of how organic chemistry works in space.
In this context, protostellar shocks are particularly well-suited to study the formation and destruction pathways of organic molecules, since the sputtering and shattering of dust grains release atoms and molecules previously settled in the dust grain cores and mantles into the gas phase. This triggers a rich warm chemistry that evolves over time. An illustrative example is the molecular outflow driven by the protostar L1157, which creates several chemically-rich shocked regions along its path. I will present interferometric observations of various organic molecules such as formamide (NH2CHO), acetaldehyde (CH3CHO), and methanol (CH3OH), along the entire Southern outflow lobe driven by the L1157 protostar, carried out with NOEMA (Northern Extended Millimetre Array). The molecular maps cover two main shocked regions with different ages, which, combined with astrochemical modelling, allows us to assess the time evolution of the targeted organic molecules' chemistry. Based on our results, I will show the importance of gas-phase chemistry in the production of formamide and other organic molecules in protostellar shocks.