Cosmic Chemistry Unveiled - The Genesis of Methyl Cations in Protoplanetary Disk Photochemistry

Forty years ago it was proposed that gas phase organic chemistry in the interstellar medium can be initiated by the methyl cation CH 3 + ( 1–3 ), but hitherto it has not been observed outside the Solar System ( 4, 5 ). Alternative routes involving processes on grain surfaces have been invoked ( 6, 7 ). Here we report JWST observations of CH+3CH3+ in a protoplanetary disk in the Orion star forming region. We find that gas-phase organic chemistry is activated by UV irradiation. Introduction : In the realm of cosmic evolution, protoplanetary disks serve as the cradles of new star systems and planetary bodies. These disks, composed of gas and dust, harbor an intricate web of chemical reactions that sculpt the materials essential for planet formation. Among the diverse array of chemical species within these disks, the methyl cation (CH3+) stands out as a key molecular fragment. Recent research has shed light on the intriguing formation of the methyl cation through photochem...