Molecules At Planet-forming Scales in the ALMA/JWST Era – MAPSAJE

How does a cloud of molecular gas and dust evolve to form a planetary system? What interstellar heritage does the latter retain? Does the chemical composition remain unchanged from molecular nebulae to emerging planets? Or does it reflect processes characteristic of the birth environment in which planets form? What are the necessary conditions to form a planetary system similar to the Solar System? Are they frequent?

Circumstellar gas- and dust-rich discs where planets form are ideal objects to answer these questions. Currently, the last generation of telescopes reveals the diversity and chemical richness of these discs. Recent images obtained with start-of-the-art radio-interferometers such as ALMA and NOEMA have provided the first evidence of continuous formation of planets in discs which are 0.1 to 10 million years old, via the observation of bright and dark rings in their distribution of dust and molecular gas. The chemical composition of planets is therefore intrinsically linked to the location and time scale of their formation.

Interpreting these observations therefore requires to understand where and how each of the molecules detected is formed, excited and then destroyed. To do this, with the MAPSAJE project we propose to combine numerical modeling and multi-wavelength observations (radio and infrared) which, thanks to current large instruments (ALMA, NOEMA, JWST, SPHERE), allow the necessary sensitivity and angular resolution to be achieved to probe all scales up to those where planets form (~ 10 AU). Our expertise in astrochemistry and in the development of precise chemical probes (isotopic, ortho / para, and key molecular ratios) at different stages of star and planet formation, while placing them in the cosmo-chemical context (via comparison with laboratory measurements or in situ) will be a key asset.