Related papers: A perspective from extinct radionuclides on a Youn…
We present a brief review of observational results contributing to modern ideas on the evolution of stellar activity. Basic laws, derived for both rotation-age and activity-rotation relationships, allow us to trace how the activity of…
I summarize recent surveys of protoplanetary disks at millimeter wavelengths and show that the distribution of luminosity, equivalent to the mass in small dust grains, declines rapidly. This contrasts with statistics on the lifetime of…
Models of the Sun's long-term evolution suggest that its luminosity was substantially reduced 2-4 billion years ago, which is inconsistent with substantial evidence for warm and wet conditions in the geological records of both ancient Earth…
Since the discovery of the first exoplanet orbiting a Sun-like star, the confirmation of nearly 6000 exoplanets to date - and their diversity - has revolutionized our knowledge of planetary systems in the past three decades. Nevertheless,…
The Solar System formed about 4.6 billion years ago from a condensation of matter inside a molecular cloud. Trying to reconstruct what happened is the goal of this chapter. For that, we put together our understanding of Galactic objects…
We review the formation and early evolution of the most massive and dense young stellar clusters, focusing on the role they can play in our understanding of star and planet formation as a whole. Young massive cluster (YMC) progenitor clouds…
The Capture Theory gives planet production through a tidal interaction between a condensed star and a diffuse protostar within a dense embedded cluster. Initial extensive and highly eccentric planetary orbits round-off and decay in a…
The recent rapid progress in observations of circumstellar disks and extrasolar planets has reinforced the importance of understanding an intimate coupling between star and planet formation. Under such a circumstance, it may be invaluable…
Debris disks are the dust disks found around ~20% of nearby main sequence stars in far-IR surveys. They can be considered as descendants of protoplanetary disks or components of planetary systems, providing valuable information on…
Young exoplanets provide a critical link between understanding planet formation and atmospheric evolution. Direct imaging spectroscopy allows us to infer the properties of young, wide orbit, giant planets with high signal-to-noise. This…
Planet-forming circumstellar disks are a fundamental part of the star formation process. Since stars form in a hierarchical fashion in groups of up to hundreds or thousands, the UV radiation environment that these disks are exposed to can…
In the late stages of accretion leading up to the formation of planetesimals, particles grew to pebbles the size of 1-mm to tens of cm. That is the same size range that dominates the present-day comet mass loss. Meteoroids that size cause…
Cool a piece of the Sun to 1000 K at one millibar pressure to yield a mineral assemblage consistent with those found in the most primitive meteorites. This is an equilibrium or fractional condensation experiment simulated by calculations…
High temperature condensates found in meteorites display uranium isotopic variations (235U/238U) that complicate dating of the formation of the Solar System and whose origin remains mysterious. It is possible that these variations are due…
Since the first massive planet in a short period orbit was discovered, the question arised how such an object could have formed. There are basically two formation scenarios: migration due to planet-disk or planet-planet interaction. Which…
Isotopic ratios provide a powerful tool for understanding the origins of materials, including the volatile and refractory matter within solar system bodies. Recent high sensitivity observations of molecular isotopologues, in particular with…
Recently K2 and TESS have discovered transiting planets with radii between $\sim$ 5-10 R$_\oplus$ around stars with ages $<100$ Myr. These young planets are likely to be the progenitors of the ubiquitous super-earths/sub-neptunes, that are…
The compositions of planet-forming disks are set by a combination of material inherited from the interstellar medium and material reprocessed during disk formation and evolution. Indeed, comets and primitive meteorites exhibit…
We use N-body simulations of star cluster evolution to explore the hypothesis that short-lived radioactive isotopes found in meteorites, such as 26-Al, were delivered to the Sun's protoplanetary disc from a supernova at the epoch of Solar…
This review addresses the state of research that employs astronomical (remote sensing) observations of solids ("dust") in young circumstellar disks to learn about planet formation. The intention is for it to serve as an accessible,…