• One of the most important processes for galaxy formation and evolution ! • Big questions! – When and how does star formation occur ?! – How is it related to the evolution of galaxy properties?! – What are the physical processes that drive star formation ?! • star formation occurs (at least in spirals at low z) almost exclusively associated with molecular clouds! – what is the rate at which st...

A review is presented of some of the ingredients, assumptions and techniques that are used in the computation of the structure and evolution of low-mass stars. Emphasis is placed on several ingredients which are still subject to considerable uncertainty. An overview of the evolution of low-mass stars is also presented, from the cloud collapse phase all the way to the white dwarf cooling curve.

This review covers the properties of disks around pre-main– sequence stars. It is at this time in the evolution that planets form, and it is important to understand the properties of these disks to understand planet formation. I discuss disk shapes, masses and temperatures, the properties of the host stars, disk lifetimes and dissipation processes. Finally, evidence of grain growth during pre-m...

This paper outlines astrophysical issues related to the long-term fate of the universe. The authors consider the evolution of planets, stars, stellar populations, galaxies, and the universe itself over time scales that greatly exceed the current age of the universe. Their discussion starts with new stellar evolution calculations which follow the future evolution of the low-mass (M-type) stars t...

The 12 C/ 13 C ratio has been measured in a sample of 10 carbon stars with high mass-loss rates, of ≥ 10 −5 M yr −1. This sample is complete for northern hemisphere carbon stars within ∼ 1 kpc of the Sun. Using the J=2–1 rotational lines of CO and 13 CO, the intensity ratio of 12 CO/ 13 CO is found to be 17 ± 11 for the sample, and the deduced 12 C/ 13 C abundance ratio, after corrections for C...