CH3NCO detections in observations and the laboratory

Methyl isocyanate (CH₃NCO) belongs to a select group of peptide-like prebiotic molecules. In this paper we present its first detection toward the solar type low-mass protostar IRAS16293-2422 (hereafter IRAS16293). CH₃NCO is detected towards IRAS16293 as a warm component with T_ex > 100 K and HNCO/CH₃NCO ~4-12. Also, its grain surface formation route is investigated in the laboratory. VUV processing of CH₄:HNCO mixtures, investigated by IR spectroscopy and mass spectrometry, revealed that it can be formed by reactions of CH₃ and with (H)NCO. Observations and experiments strongly hint that methyl isocyanate is formed on interstellar dust grains.