MAPS: Molecules with ALMA at Planet-forming Scales

Planets form in disks around young stars. The material available in these protoplanetary disks will eventually be accreted onto the star, blown out by winds or incorporated into planets. The chemical composition of nascent planets is therefore directly linked to the disk chemical structures. The distribution of molecules across disks will determine the elemental composition of planets (C/N/O/S) and their access to water and key organic species depending on where they form in the disk. Molecular lines are also powerful tracers of important parameters for planet formation and disk evolution, such as disk ionization, temperature structures, kinematics and gas surface densities.

In this talk I will highlight the key results of the ALMA Large Program MAPS (Molecules with ALMA at Planet-forming Scales), that was designed to explore the radial and vertical chemical structures in 5 disks with high-angular resolution (7- 30 au). The five disks, IM Lup, GM Aur, AS 209, HD 163296 and MWC 480, present dust sub-structures and appear to have ongoing planet formation. We observed ~40 lines from 20 different molecular species, in 4 spectral settings in both band 6 and band 3. The first results of this program will be presented in a series of 20 papers that span a range of topics. All the data and a series of data products will be made available to the community so that this incredibly rich dataset can be used to continue exploring the chemistry that affects and probes planet formation.