Stars and planets are formed from interstellar matter in galaxies. The densest parts of interstellar clouds collapse to form protostars surrounded by disks. These « protoplanetary disks » are the nurseries for planetary systems. The dynamics, density structure, temperature, chemical composition, dust-to-gas ratio in interstellar clouds and disks are key ingredients to determine the initial conditions of stars and planets, and the evolution of the new protostars and protoplanets in their native disk. The unprecedented performances and instrumental capabilities of the JWST will allow an incredible jump in the observations from the interstellar medium to disks and exoplanets.

A suite of 4 instruments is located at the focal plane of the telescope:

• A Near-IR Imager and Slitless Spectrograph (0.6-5 μm): NIRISS, provided by CSA,
• A Near-IR CAMera (0.6-5 μm): NIRCAM, provided by the University of Arizona,
• A Near-IR SPECtrometer (1-5 μm): NIRSPEC,  provided by ESA, with components provided by NASA/GSFC,
• A Mid-IR Instrument (5-28 μm): MIRI provided by a European Consortium of laboratories under the auspices of ESA, and by the NASA Jet Propulsion Laboratory (JPL).

Two astrophysical laboratories members of the P2IO LabEx, Irfu-DAp and IAS, are members of the MIRI consortium. MIRI offers a suite of versatile observing capabilities including imaging, low and moderate resolution spectroscopy and coronagraph.The French participation in MIRI is focused on the imager, under the technical and scientific management of Irfu-DAp. CNES is responsible to ESA for the French contribution.

Paris-Saclay teams working on extraterrestrial matter (from Irfu-Dap, IAS and IJCLab in the P2IO Labex, and also ISMO and Maison de la Simulation) have come together to propose a project in order to prepare for the interpretation of the JWST observations. The goal is to bring a complete understanding of the different physical processes, at micro and macro scales and in relation with the dynamics and the physical and chemical properties, which are acting in the evolutionary sequence from the interstellar medium to the formation of planets.

The project is organized in three scientific work packages:

1. Preparation of JWST observations:  preparation of JWST observation programs (for interstellar clouds, protoplanetary disks and exoplanets), data simulations, development of high level data reduction pipelines, data challenges, …
2. Modeling and Simulations: exoplanet atmospheres, dust models coupled to radiative transfer codes used to analyse pre-JWST data from Photo Dominated Regions and protoplanetary disks.
3. Laboratory experiments: extraterrestrial samples (Interplanetary Dust Particles, Ultracarbonaceous Antarctic Micrometeorites from the CONCORDIA collection, asteroid samples) and analogues analyzed using multiple techniques (FTIR, Raman, STXM C-and N-XANES, TEM, NanoSIMS, AFM-IR, IR spectroscopy, Hyperspectral imaging, Irradiation, …)  and in different local and national facilities (Soleil, ANDROMED, GANIL,  …)

• Site with comparaison of Hubble and JWST images
• Link to download the JWST images
• Relive the ARTE Twitch on the Discovery of the James Webb Telescope 
• Link to the NASA video of July12