FIGURE 1 ATOMIC AND MOLECULAR PHYSICS, DILUTE MATTER, UNIVERSE SCIENCE SYNCHROTRON SOLEIL HIGHLIGHTS 2020 AILES BEAMLINE Associated publication First detection of NHD and ND2 in the interstellar medium. Melosso, M., Bizzocchi, L., Sipilä, O., Giuliano, B.M., Dore, L., Tamassia, F., Martin-Drumel, M.A., Pirali, O., Redaelli, E., Caselli, P. Astronomy & Astrophysics., 641: art.n° A153. (2020) Corresponding author Mattia Melosso It should also be pointed out that despite the low cosmic abundance of CHIM - Dipartimento di Chimica deuterium (around 0.0015 % of the hydrogen abundance), the observed "Giacomo Ciamician" Via Selmi 2 abundances of NHD and ND are quite high, between 10 and 80 % of 40126 Bologna 2 mattia.melosso2@unibo.it that of NH. Indeed, deuterated molecules can be found in the interstellar2 medium in very large amounts: this is due to the so-called “deuterium fractionation processes”, i.e. the deuterium enrichment in a given Caption molecules, which may occur efficiently under certain physical conditions, FIGURE 1: Mattia Melosso acknowledges Brett A. as for example a low gas temperature (5–20 K). These conditions are McGuire for his inspiring tweet and Ningjing Jiang for the often found in very young stars (protostars), thus making them an ideal wonderful figure. laboratory to study deuterated species. However, such a high enhancement can hardly be explained by astrochemical models and future observations of these species might provide more insights into the mechanism of ammonia formation and deuteration in the interstellar medium. 59