Related papers: Infall and Disk Processes - the Message from Meteo…
The bulk chemical compositions of planets are uncertain, even for major elements such as Mg and Si. This is due to the fact that the samples available for study all originate from relatively shallow depths. Comparison of the stable isotope…
The disks that orbit young stars are the essential conduits and reservoirs of material for star and planet formation. Their structures, meaning the spatial variations of the disk physical conditions, reflect the underlying mechanisms that…
The formation and early evolution of protoplanetary disks are governed by a wide variety of physical processes during a gravitational collapse. Observations have begun probing disks in their earliest stages, and have favored the…
The late stages of stellar evolution from asymptotic giant branch stars to planetary nebulae are now known to be an active phase of molecular synthesis. Over 80 gas-phase molecules have been detected through rotational transitions in the…
The heavy elements formed by neutron capture processes have an interesting history from which we can extract useful clues to and constraints upon both the characteristics of the processes themselves and the star formation and…
Spiral galaxies are thought to acquire their gas through a protracted infall phase resulting in the inside-out growth of their associated discs. For field spirals, this infall occurs in the lower density environments of the cosmic web. The…
Despite being all roughly of solar composition, primitive meteorites (chondrites) present a diversity in their chemical, isotopic and petrographic properties, and in particular a first-order dichotomy between carbonaceous and…
High-spatial-resolution observations of disks around young stars suggest planetary systems begin forming early, during the protostellar phase (< 1 Myr) when stars accrete most of their mass via infall from the surrounding cloud. During this…
Planets that form early enough to be embedded in the circumstellar gas disk accumulate thick atmospheres of nebular gas. Models of these atmospheres need to specify the surface luminosity (i.e. energy loss rate) of the planet. This…
Organic material found in meteorites and interplanetary dust particles is enriched in D and 15N. This is consistent with the idea that the functional groups carrying these isotopic anomalies, nitriles and amines, were formed by ion-molecule…
Using a representative sample of Milky Way (MW)-like galaxies from the TNG50 cosmological simulation, we investigate physical processes driving the formation of galactic disks. A disk forms as a result of the interplay between inflow and…
Infall of interstellar material is a potential non-planetary origin of pressure bumps in protoplanetary disks. While pressure bumps arising from other mechanisms have been numerically demonstrated to promote planet formation, the impact of…
We review current understanding of star formation, outlining an overall theoretical framework and the observations that motivate it. A conception of star formation has emerged in which turbulence plays a dual role, both creating…
The disk instability mechanism for giant planet formation is based on the formation of clumps in a marginally-gravitationally unstable protoplanetary disk, which must lose thermal energy through a combination of convection and radiative…
Since the discovery of the first extra-solar planets, we are confronted with the puzzling diversity of planetary systems. Processes like planet radial migration in gas-disks and planetary orbital instabilities, often invoked to explain the…
Nucleosynthetic isotopic anomalies in meteorites and planetary objects contribute to our understanding of the formation of the solar system. Isotope systematics of chondrites demonstrate the existence of a physical separation between…
In this review, three major changes in our understanding of the early history of the Solar System are presented. 1) Early differentiation: A few recent results support the idea that protoplanet formation and differentiation occurred partly…
In view of the many recent observations conducted by ALMA and SPHERE, it is becoming clear that protoplanetary disks form planets in narrow annular gaps at various distances from the central protostars before these protostars are actually…
Carbonaceous chondrites are some of the most primitive meteorites and derive from planetesimals that formed a few million years after the beginning of the solar system. Here, using new and previously published Cr, Ti, and Te isotopic data,…
The planet-forming disk of HD 142527 is known for its azimuthally asymmetric dust trap, shadows, and spiral arms. We use new ALMA observations to investigate the molecular composition and to determine the ongoing chemical processes and the…