Observational campaigns are revealing thousand of exoplanets, showcasing that planet formation is an extremely efficient mechanism around most stars during their infancy. The same observations also indicate that exoplanets exhibit a wide diversity in their properties, such as radius, mass, orbital separations, and chemistry of their atmospheres. The natal environments of these planets are disks of gas and dust orbiting new-born stars, and they are called protoplanetary disks. Highly detailed images of these disks show potential signatures of dynamical interactions of growing planets within their structure, but at the moment only very few planets have been detected while they are still accreting mass in their protoplanetary disk! Thanks to the revolutionary capabilities of recent and new facilities observing the sky at different wavelengths, such as ALMA in the Atacama desert, and JWST from space, the time is ripe to finally detect more planets in the act of formation. This is fundamental to observe directly how their bulk and atmospheric properties is determined by the physics and chemistry of their birth surroundings. The ERC project UNVEIL will bridge the gap between exoplanets and planet forming disks by directly observing and modelling the assembly of massive planets in disks at large orbital radii. By leveraging extremely deep new data, the aims of the project are multi-faceted. First, we will observationally characterize how the gas motions (dynamics) can support the formation of planetary cores, the seeds of massive planets. Second, we will search for these massive planets with two distinct methodologies: (a) we will look for feeble waves propagating in the protoplanetary disk, which originate from the growing protoplanets, to unveil their presence; (b) we will try to image these protoplanets themselves in the infrared, which is the most prominent color of their emission light. Finally, we will directly connect the chemistry of protoplanetary disks with the chemistry of these growing protoplanets, by using special techniques to extract this information. This project builds upon a novel methodology to detect protoplanets in the wave pattern of protoplanetary disks, and upon novel datasets that we recently obtained from both ALMA and JWST. In summary, this ERC project will provide observational constraints that are sorely needed to unveil the formation phases of cores and atmospheres of exoplanets that are similar to Jupiter and Saturn in our own Solar System.
